Audiobook: Theory of the Earth, With Proofs and Illustrations, Volume 2 (of 4) by Hutton, James

Project Gutenberg's Theory of the Earth, Volume 2 (of 4), by James Hutton

This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org

Title: Theory of the Earth, Volume 2 (of 4)

Author: James Hutton

Release Date: November 27, 2004 [EBook #14179]

Language: English

Character set encoding: ISO-8859-1

*** START OF THIS PROJECT GUTENBERG EBOOK THEORY OF THE EARTH ***

Produced by Robert Shimmin, Renald Levesque and the PG Online Distributed Proofreading Team.

THEORY OF THE EARTH

WITH PROOFS AND ILLUSTRATIONS.

IN FOUR PARTS.

BY JAMES HUTTON, M.D. AND F.R.S.E.

VOL. II.

1795

CONTENTS.

PART II.

Farther Induction of Facts and Observations, respecting the Geological Part of the Theory

INTRODUCTION

CHAP. I.

Facts in Confirmation of the Theory of Elevating Land above the Surface of the Sea.

CHAP. II.

The same Subject continued, with Examples from different Countries.

CHAP. III.

Facts in confirmation of the Theory, respecting those Operations which re-dissolve the Surface of the Earth.

CHAP. IV.

The same Subject continued, in giving still farther Views of the Dissolution of the Earth.

CHAP. V.

Facts in confirmation of the Theory respecting the Operations of the Earth employed in forming Soil for Plants.

CHAP. VI.

A View of the Economy of Nature, and necessity of Wasting the Surface of the Earth, in serving the purposes of this World.

CHAP. VII.

The same Subject continued, in giving a View of the Operations of Air and Water upon the Surface of the Land.

CHAP. VIII.

The present Form of the Surface of the Earth explained, with a View of the Operation of Time upon our Land.

CHAP. IX.

The Theory Illustrated, with a View of the Summits of the Alps.

CHAP. X.

The Theory Illustrated, with a View of the Valleys of the Alps.

CHAP. XI.

Facts and Opinions concerning the Natural Construction of Mountains and Valleys.

CHAP. XII.

The Theory Illustrated, by adducing Examples from the different Quarters of the Globe.

CHAP. XIII.

The same Subject continued.

CHAP. XIV.

Summary of the Doctrine which has been now Illustrated.

FARTHER INDUCTION OF FACTS AND OBSERVATIONS, RESPECTING THE GEOLOGICAL PART OF THE THEORY.

INTRODUCTION.

By the present theory, the earth on which we dwell is represented as having been formed originally in horizontal strata at the bottom of the ocean; hence it should appear, that the land, in having been raised from the sea, and thus placed upon a higher level, had been of a different shape and condition from that in which we find it at the present time. This is a proposition now to be considered.

In whatever order and disposition the hard and solid parts of the land were at the time of its emerging from the surface of the sea, no provision would have then been made for conducting the rivers of the earth; therefore, the water from the heavens, moving from the summits of the land to the shores, must have formed for themselves those beds or channels in which the rivers run at present; beds which have successively changed their places over immense extents of plains that have often been both destroyed and formed again; and beds which run between the skirts of hills that have correspondent angles, for no other reason but because the river has hollowed out its way between them.

In this view of things, the form of our land must be considered as having been determined by three different causes, all of which have operated, more or less, in producing the present state of those things which we examine. First, There is a regular stratification of the materials, from whence we know the original structure, shape, and situation of the subject. Secondly, There are the operations of the mineral region, some of which have had regular effects upon the strata, as we find in the veins or contractions of the consolidated masses; others have had more irregular effects, but which may still be distinguished by means of our knowing the original state and structure of those masses. Lastly, There are operations proper to the surface of this globe, by which the form of the habitable earth may be affected; operations of which we understand both the causes and the effects, and, therefore, of which we may form principles for judging of the past, as well as of the future. Such are the operations of the fun and atmosphere, of the wind and water, of the rivers and the tides.

It is the joint operation and result of those three different causes that are to be perceived in the general appearances of this earth, and not the effects of any one alone; although, in particular places of the earth, the operation peculiar to each of these may be considered by itself, in abstracting those of the others, more or less. Thus there are several views in which the subject is to be examined, in order to find facts with which the result of the theory may be compared, and by which confirmation may be procured to our reasoning, as well as explanation of the phenomena in question.

CHAPTER I.

Facts in confirmation of the Theory of Elevating Land above the Surface of the Sea.

The first object now to be examined, in confirmation of the theory, is that change of posture and of shape which is so frequently found in mountainous countries, among the strata which had been originally almost plain and horizontal. Here it is also that an opportunity is presented of having sections of those objects, by which the internal construction of the earth is to be known. It is our business to lay before the reader examples of this kind, examples which are clearly described, and which may be examined at pleasure.

No person has had better opportunities of examining the structure of mountains than M. de Saussure, and no body more capable of taking those comprehensive views that are so necessary for the proper execution of such a task. We shall therefore give some examples from this author, who has every where described nature with a fidelity which even inconsistency with his system could not warp. Speaking of the general situation of the beds of the Saleve, (p. 179.)

�Dans quelques endroits, et m�me presque partout, les couches descendent tout droit du haut de la montagne jusques � son pied: mais au dessus de Collonge le sommet arrondi en dos d'�ne pr�sente des couches qui descendent de part et d'autre, au sud-est vers les Alpes, et au nord-ouest vers notre vall�e; avec cette difference, que celles qui descendent vers les Alpes parviennent jusques au bas; au lieu que celles qui nous regardent sont coup�es � pic, � une grande hauteur.

�Ces deux inclinaisons ne sont pas les seules que l'on observe dans le bancs du mont Saleve, ils en ont encore une troisi�me; ils sont relev�s vers le milieu de la longueur de la montagne, et descendent de l� vers ses extr�mit�s. Cette pente, qui sur le Grand Saleve n'est pas bien sensible, devient tr�s remarquable au Petit Saleve, et m�me tr�s rapide � son extr�mit�. Les derni�res couches au nord au dessus d'�trembi�res descendent vers le nord-nord-est, sous un angle de 40 au 50 degr�s.

�On verra, dans le cours de cet ouvrage, combien le montagnes calcaires ont fr�quemment cette forme.

�� 235. Outre ces grandes couches qui constituent le corps de la montagne, et qui peuvent en g�n�ral �tre mises dans la classe des couches horizontales, on en trouve d'autres dont l'inclinaison est absolument diff�rente. Elles sont situ�s au bas de Grande Saleve du cot� qui regarde notre vall�e; on les voit appliqu�es contre les tranches inf�rieures des bancs horizontaux ou tr�s-inclin�es en appui contre la montagne.

�Ces couches s'�l�vent en quelques endroits, par exemple, entre Veiry et Cr�vin, � peu-pr�s � la moiti� de la hauteur du Grande Saleve. Celles qui touchent imm�diatement la montagne, sont le plus inclin�es; on en voit l� de verticales et m�me quelque fois de renvers�es en sens contraire, qui sont soutenues par le plus ext�rieures. Celle ci font avec l'horizon un angle de 60 � 65 degr�s. Ces couches sont souvent tr�s �tendues, bien suivies, et continues � de tr�s-grandes distances. Leur assemblage forme une �paisseur consid�rable au pied de la montagne. Elles ont cependant �t� rompues, et manquent m�me totalement dans quelques places. Cela m�me donne la facilit� de les bien observer, parce qu'en se postant dans ces intervalles, on peut les prendre en flanc, et voir distinctement leurs tranches, et tout leur structure.

�On observe ces couches non-seulement au pied de rocs nuds du Grand Saleve, mais encore dans la partie de sa pente qui est bois�e par exemple au dessous de la croisette, le chemin qui de ce hameau descend au village de Collonge, passe sur les couches inclin�es, comme celles que je viens de d�crire.�

In � 237, the description is continued.

�En suivant le pied de la montagne entre le Coin et Cr�vin, on voit repara�tre nos couches verticales ou tr�s inclin�es qui vis � vis du Coin, ont �t� d�truites comme je viens de le dire. Ces couches l� ou elles sorte que l'on peut comparer toutes les couches de la montagne � celles d'un jeu de cartes ploy� en deux suivant sa longueur.�

In considering the chains of the Jura, on the west side of that which looks to the lake, our author has the following interesting observations, p. 275.

�Les cha�nes dont il est compos�, � mesure qu'ils s'�loignent de la haute ligne orientale perdent graduellement de leur hauteur et de leur continuit�; le plus occidentales ne forment pas, comme la premiere, des cha�nes de montagnes �lev�e et non interrompues; ce sont des monticules allong�s il est vrai, mais isol�s ou qui du moins ne sont unis que par leurs bases.

�� 338. Leur structure n'est pas la m�me dans toute l'�tendue du Jura. La forme primitive la plus g�n�rale ressemble cependant � celles de la haute cha�ne; c'est-�-dire, que ce sont de vo�tes, compos�es et remplies d'arcs concentriques.

�C'est surtout entre Pontarlier et Besan�on, que l'on rencontre des collines qui ont r�guli�rement cette structure. La grande route traverse de larges vall�es, dans lesquelles les couches sont horizontales; mais ces vall�es sont s�par�es par des cha�nes peu �lev�es dont le couches arqu�es montent jusques au haut de la montagne, et descendent ensuite du cot� oppos�. On en voit aussi de la m�me forme dans la Pr�v�t� de Moutier Grand Val. La birs traverse des rochers qui offrent � d�couvert la construction int�rieure des montagnes; les couches de roc forment dans cet endroit des vo�tes �lev�es l'une sur l'autre en suivant le contour ext�rieur de la montagne.--Dict. G�og. de la Suisse, tom. 2. p. 150.

�D'autres fois le sommet de la montagne est plus aigu que n'est celui d'une vo�te, et les couches paralelles entr'elles, mais inclin�es � l'horizon en sens contraire, pr�sentent dans leur section, la form d'un chevron ou d'un lambda [Greek: L].

�� 339. Mais cette m�me structure presente fr�quemment une singularit� remarquable. Ce sont des bancs perpendiculaires � l'horizon qui occupent �-peu-pres le milieu ou le coeur de la montagne et qui s�parent les couches d'une des faces de celles de la face oppos�e.

�J'ai observ� plusieurs montagnes secondaires, et du Jura et d'ailleurs, et surtout un grande nombre de montagne primitive, dont la structure est la m�me[1].�

[Footnote 1: This correspondency in the shape of the primitive and secondary mountains of our author, of which the structure is the same, is an important observation for our theory, which makes the origin of those two different things to be similar; it is inconsistent, however, with the notion of primitive parts, which some philosophers have entertained.]

�� 340. Les couches perpendiculaires � l'horizon, que l'on rencontre fr�quemment dans le Jura ont presque toutes leurs plans dirig�s du nord-nord-est au sud-sud-ouest, suivant la direction g�n�rale de cette cha�ne de montagne. Cette observation est d'une assez grande importance parce qu'elle exclut ou rend du moins improbable l'id�e d'un bouleversement.

�J'ai cru pendant long-temps que toutes les couches d�voient avoir �t� form�es dans une situation horizontale, ou peu inclin�e � l'horizon, et que celles que l'on rencontre dans une situation perpendiculaire, ou tr�s-inclin�es, avoient �t� mises dans cet �tat par quelque r�volution; mais � force de rencontrer des couches dans cette situation, de les voir dans de montagnes bien conserv�es, et qui ne paroissoient point avoir subi de bouleversement, et d'observer une grande r�gularit� dans la forme et dans la direction de ces couches; je suis venu � penser que la nature peut bien avoir aussi form� de ces bancs tr�s-inclin�s, et m�me perpendiculaire � la surface de la terre.�

Here the reasoning of our author is sufficiently just; he sees too much order in the effect to ascribe it to a cause merely fortuitous. But surely nothing in those appearances hinders the conclusion, that the strata now found in ail possible positions, had been originally horizontal when at the bottom of the sea, and that they had been afterwards regularly bent and broken, by the same cause which operated in placing them above the level of the ocean. The force of this argument will appear, by considering the various regular and irregular positions in which they are found.

�� 242. Dans quelques endroits du Jura, on voit des esp�ces de demi-cirques form�s par des rochers dont le couches sont de portions de la surface d'un m�me c�ne et tendent � un centre commun �lev� au dessus de l'horizon.

�Ainsi aupr�s de Pontarlier, etc.

�� 343. Mais il est bien plus fr�quent de voir des montagnes dont les couches ont la forme d'une demi-vo�te, et qui vues de profil pr�sentent, comme notre montagne de Saleve, un pente douce d'une cot�, et des escarpemens de l'autre.

�Plusieurs vall�es du Jura sont situ�es entre deux chaine de montagnes qui ont cette forme, et qui se presentent r�ciproquement leur faces escarp�es. On croit m�me apercevoir quelque correspondance, entre les couches de ces montagnes oppos�es, et l'on diroit qu'elles furent anciennement unies, et que la partie interm�diaire a �t� d�truite, ou que la montagne s'est fendue du haut en bas, et que ses deux moiti�s se sont �cart�es pour faire place � la vall�e qu'elles renferment.

�� 346. Pour r�sumer en peu de mots les id�es que je me forme de la structure du Jura; je dirai que je crois qu'il est compos� de diff�rentes cha�nes �-peu-pr�s paralleles entr'elles, et � celles des Alpes, mais tirant un peu plus du nord au midi: que la chaine la plus �lev�e et la plus voisine des Alpes, a eu originairement la forme d'une dos d'�ne dont les pentes partent du faite, recouvrent les flancs, et descendent jusques au pieds de la montagne: que les cha�nes suivantes du cot� de l'ouest, sont compos�es de montagnes graduellement moins �lev�es et moins �tendues; que les couches de ces montagnes ont g�n�ralement la forme de vo�tes enti�res ou de moiti� de vo�tes; et qu'elles viennent mourir dans des plaines, qui ont pour base des bancs calcaires tout � fait horizontaux de la m�me nature que ceux du mont Jura, et qui furent peut-�tre anciennement continus avec eux.�

Our author has here described most accurately, not only the present shape and positions of particular strata, but the general shape and structure of the land him the Saleve and Jura, which are not in the Alps, to the plains of France, where the strata are generally in a more horizontal situation.

Having thus seen the structure of what are commonly termed the secondary mountains, a structure which prevails generally in all parts of the land, at least in all that which is not primitive in the estimation of naturalists, who suppose a different origin to different parts, it will now be thought a most interesting view of nature, to see the same accurate examination of the structure of the earth, from those secondary mountains of Geneva to the center of the Alps, where we find such a variety of mountains of different materials, (whether they shall be called primitive or secondary) and where such opportunity is found for seeing the structure of those mountains. For, if we shall find the same principles, here prevailing in the formation of those supposed primitive mountains as are found over all the earth in general, and as are employed in fashioning or shaping every species of material, it will be allowed us to conclude, that, in this situation of things, we have what is general in the formation of land, notwithstanding imaginary distinctions of certain parts which had been formed one way, and of others which are supposed to be operations of an opposite nature.

This question therefore will be properly decided in our author's journey to the Alps; for, if we shall there find calcareous strata perfectly consolidated, as they should be by the extreme operation of subterranean heat and fusion; if we find materials of every species formed after the manner of stratification; and if all those different strata variously consolidated shall be found in all positions, similar to those which we have now seen in the examination of the Jura and Saleve, with this difference, that the deplacement and contorsion may be more violent in those highly consolidated strata, we shall then generalise an operation by which the present state of things must have been produced; and in those regular appearances, we shall acknowledge the operation of an internal heat, and of an elevating power.

�� 287. Les pentes rapides des bancs dont est form� le mole, les directions vari�es de ces m�mes bancs sont aussi conformes � une observation g�n�rale et importante, que le montagnes secondaires sont d'autant plus irr�guli�res et plus inclin�es qu'elles s'approchent plus des primitives.

�A la verit�, quelque montagnes calcaires m�me � de grandes distances des primitives ont �a et l� des couches inclin�es et m�me quelquefois verticales; mais ces exception locales n'emp�chent pas qu'il ne soit vrai qu'en general, les bancs calcaires, que l'on trouve dans les plaines qui sont �loign�es des hautes montagnes, ont leurs bancs ou horizontaux ou peu inclin�s; tandis, qu'au contraire, les montagnes qui s'approchent, du centre des grands cha�nes, n'ont que tr�s-rarement des couches horizontales, et presentent presque par-tout des couches fortement et diversement inclin�es.�

That is to say, that there is no place of the earth, however plain and horizontal in general may be the strata, in which examples are not found of this manner of disordering or displacing strata; at the same time they are more crested and more disordered in proportion to the mountainous nature of the country. Here is the proposition contained in that general observation of natural history; and this is a proposition which either naturally flows from the theory, or is perfectly consistent with it.

�� 360, a. Le rocher dont j'ai parl� (� 354) qui touche celui de la Dole, et qui porte le nom de Vouarne, est d'une structure singuli�re. Les bancs dont il est compos� sont escarp�s, les uns en montant contre le nord-est sous un angle de 40 � 50 degr�s; les autres en s'�levant contre le sud-est.

�� 361. En avant de ce rocher, du cot� l'est, on en voit un autre d'une structure tr�s remarquable. Il a la forme d'un chevron aigu ou d'un lambda [Greek: L]. on le nomme, sans doute � cause de sa forme, le Rocher de fin Ch�teau. Les bancs dont il est compos� sont tr�s inclin�s � l'horizon, et s'appuient r�ciproquement contre leurs sommit�s respectives. Les planches que l'on dresse en appui les unes contre les autres pour les faire secher, peuvent donner une id�e de la situation de les bancs. Cette forme n'est pas rare dans ces rochers calcaires; mais elle est bien plus fr�quente encore, et plus d�cid�e dans le rochers primitifs, comme nous le verrons dans la suite.

�Le rocher de fin ch�teau presente dans cette forme m�me une circonstance tr�s-remarquable; c'est que l'intervalle que les jambes du lambda [Greek: L] laissent entr'elles, est rempli par des couches perpendiculaires � l'horizon. On diroit que ces couches chass�es en haut par une force souterraine, ou soulev� de part et d'autre, des bancs qui sont demeur�s appuy�s contre elles. Nous avons d�j� vu des rochers de cette forme, � 339.�

Here the truth of our theory is so evident, that this philosopher naturally acknowledges it without intention.

In his Journey to Mont Blanc, he observes, page 364,

�Un peu au del� de Contamine on passe sous les ruines du ch�teau de Faucigny, b�ti sur le sommet d'un rocher escarp�, qui fait partie de la base du m�le. Tant qu'on est imm�diatement au dessous de ce rocher on ne d�m�le pas bien sa structure; mais apr�s l'avoir passe, on peut voir � l'aide d'une lunette, qu'il est compos� de couches perpendiculaires � l'horizon, et dirig�es du nord-est au sud-ouest. Au dessous de ce rocher au sud-est, on voit d'autres couches verticales, mais dont les plans coupent � l'angle droits ceux des premiers.

�A une bonne demi-lieue de ce ch�teau on observe, comme au pied du Mont Saleve, une masse de rochers, dont les couches minces, presque perpendiculaires � l'horizon, sont adoss�es aux escarpemens de couches �paisses et bien suivies, qui paroissent horizontales.�

Speaking of the Mont Brezon, our author says, page 369,

�Mais le pied de cette montagne est encore, comme celui de Saleve, couvert de grandes couches presque perpendiculaires � l'horizon et appuy�es contre le corps m�me de la montagne. Et quoique le Brezon se termine � une petite demi-lieue de la Bonne Ville, cependant ses couches qui sont appuy�es contre le pied de la cha�ne m�ridionale, et qui tournent ainsi le dos � l'Arve, continuent de r�gner jusques au village de Siongy pendant l'espace de pr�s de deux lieues. Elles sont � la verite coup�es par une petite vall�e � l'extr�mit� du pied du Brezon, mais elles recommencent au de l� de cette coupure.

�� 446. Cette petite vall�e, qui s'ouvre au pied du Brezon, est �troite et tortueuse; les angles saillans engren�es dans les angles rentrans y sont extr�mement sensibles. Elle conduit au village de Brezon, qui est situ� derri�re la montagne de ce nom.

�Au dessus de ce village sont de grands et beaux p�turages avec des chalets qui ne sont habit�s qu'en �t�, et que l'on nomme les Granges de Solaison. C'est l� que j'allois coucher quand je visitois le Brezon et les montagnes voisines. Les granges de Solaison sont domin�es, au sud-est par le monts Vergi, cha�ne calcaire tr�s �lev�e, dont j'ai aussi parcouru les sommets qui se voyent des environs de Gen�ve, sur la droite du m�le.

�Cette cha�ne court du nord-est au sud-ouest, et vient se terminer derri�re les montagnes qui bordent notre route � droite.

�� 447. On peut, des environs de Siongy, observer la structure de la derni�re montagne de cette chaine; elle est tr�s remarquable. Les couches horizontales au sommet se courbent presqu'� angles droits, et descendent de l� perpendiculairement du cot� du nord-ouest. On diroit qu'elles ont �t� ploy�es par une violent effort; on les voit s�par�es et �clat�es en divers endroits.

�� 449. Le mole se termine � la jonction du Giffre avec l'Arve; ses derni�res couches descendent avec rapidit� dans le lit de cette petite riviere,

�Les montagnes qui suivent le m�le, et qui forment apr�s lui le cot� septentrional de la vall�e de l'Arve, sont basses et indiff�rentes, une seule est remarquable par sa forme pyramidale, et par ses couches qui convergent � son sommet, et lui donnent la forme d'un chevron.

�� 450. La ville m�me de Cluse est b�tie sur le pied d'une montagne, dont la structure est tr�s extraordinaire; on en juge mieux � une certain distance que de la ville m�me.

�Cette montagne de forme conique �mouss�e, ou plut�t parabolique, est pour ainsi dire coiff�e d'une bande de rochers, qui du haut de sa t�te descendent � droite et � gauche jusques � son pied. Ces rochers nuds sont relev�es par le fond de verdure dont le reste de montagne est couverte. Ils sont compos�s de plusieurs bandes parall�les entr'elles; les ext�rieures sont blanches et �paisses, les int�rieures sont brunes et plus minces. Le corps m�me de la montagne, dont on apper�oit �� et l� les rochers au travers du bois, qui les couvre, paroi compos� de couches irr�guli�res et diversement inclin�es. On pourroit soup�onner que cette bande n'est que le reste d'une esp�ce de callote qui vraisemblablement couvroit autrefois toute la montagne.

�� 463. Des que l'on est sorti de la ville de Cluse, on voit en se retournant sur la droite, les rochers en surplomb sous lesquels on a pass� avant de traverser l'Arve. On distingue d'ici le profil des couches de ces rochers; et on reconnoit qu'elles sont presque perpendiculaires � l'horizon.

�Ces couches sont adoss�es � d'autres couches calcaires et verticales comme elles, mais qui sont la continuation de couches �-peu-pr�s horizontales: on diroit qu'une force inconnue a ploy� � angles droits l'extr�mit� de ces couches, et les a ainsi contrainte � prendre une situation verticale.

�� 467. Si du grande chemin qui est au pied de la caverne, on jette les yeux sur le rocher dans lequel est son ouverture, on observera que les bancs de ce rocher sont tr�s �pais, et compos�s d'une pierre calcaire grise; qu'au dessus cette pierre grise on en voit une autre de couleur brune, dont les couches font tr�s minces; mais qui par leur r�p�tition forment une �paisseur consid�rable.

�Ces couches de pierres � feuillets minces, continuent jusques � Sallanches et au de l�; et sont renferm�es par dessus et par dessous entre des bancs de pierre grise compacte et � couches �paisses. Quelquefois la pierre grise qui sert de base, ou comme disent les mineurs, de plancher � la brune, s'enfonce et alors celle-ci paroit � fleur de terre; ailleurs cette pierre grise se rel�ve et porte la brune � une grande hauteur.

�Cette pierre brune et feuillet�e est comme la grise de nature calcaire; mais un m�lange d'argile, et peut-�tre un peu de mati�re grasse ou phlogistique lui donnent sa couleur brune et la disposent � se rompre en fragmens angulaires et � cot�s plans.

�Ce genre de pierre est fort sujet � avoir ses couches fl�chies ou ond�es en forme de S de Z ou de C. Pr�s de la caverne, on, voit une lacune dans le milieu des bancs du roc gris; les couches minces ont rempli cette lacune, mais elles sont dans cet espace extr�mement tourment�es. On comprend que ce vide et ce remplacement, se sont faits dans le temps m�me de la formation de ces rochers.�

We have the following description of the Cascade Mountain, p. 396.

�Les couches de cette montagne sont la continuation des couches sup�rieures du rocher de la cascade, et forment des arcs concentriques, tourn�s en sens contraire; en sorte que la totalit� de ces couches a la forme d'une S, dont la partie sup�rieure se recourbe fort en arri�re.

�Le rocher de la cascade, repr�sent� par la planche IV. est tout calcaire; les couches, qui sont au dessous des lettres d et e, sont compos�es de ce roc gris compact dont les bancs, comme nous l'avons vu plus haut, sont ordinairement �pais, mais les couches ext�rieures entre e et f, sont du roc brun � couches minces, dont nous avons aussi parl�. Ces m�me couches minces se voyent encore � l'intersection de perpendiculaire qui passent par lettres a et e.

�Ici dont c'est le roc gris qui est renferm� entre deux bancs de roc brun au lieu qu'aupr�s de la caverne, c'�toit le roc brun, qui �toit resserr� entre deux bancs de roc gris; mais cette diff�rence n'est pas ce qu'il y a de plus difficile � expliquer; c'est la forme arqu�e de ces grandes couches dont il faudroit rendre raison.�

Having measured this rock geometrically, the result is as follows:

�Le plus grand des arcs de cercle que forment ces couches ext�rieures de ce rocher, a donc pour corde une ligne d'environ 800 pieds: dans toute cette �tendue, ces couches de m�me que les int�rieures sont suivies sans interruption.

�Je dois cependant avertir, qu'en avant du rocher de la cascade � la hauteur de la lettre a, et au dessous, on voit des couches d�tach�es des circulaires, et ind�pendantes d'elles; ce sont de plans inclin�s en appui contre le corps de la montagne, semblables � ceux que j'ai observ� au pied du mont Saleve, et d'une formation vraisemblablement plus r�cente que le corps m�me de la montagne.

�Mais derri�re ces plans, on voit les couches arqu�es, qui sont horizontales dans le bas, servir de base au rocher, se relever ensuite sur la droite, et venir en tournant former le faite de ce m�me rocher.�

�It may be interesting to hear our author's reasoning upon this subject, more especially as it will give more faith or light, if it were possible, to his descriptions, which are irreproachable.

�� 473. Il s'agiroit � present de dire quelle force a pu donner � ces couches cette situation; comment elles out pu �tre retrouss�es de fa�on que les plus basses soient devenues les plus �lev�es?

�La premi�re id�e qui se pr�sente est celle des eaux souterrains. Ce qui pourroit m�me faire soup�onner que ces couches ont �t� r�ellement relev�es par une force souterraine c'est que, sur la droite du rocher qu'elles forment, il y � un vide ou il manque � peu-pres ce qu'il faudroit pour former la hauteur de la cascade; car la montagne que l'on voit sous les lettres g et h, est sur une ligne beaucoup plus recul�e. Sur la droite de ce vide ces couches recommencent sur la ligne de celles qui sont recourb�es; on les voit coup�es � pic de leur cot�, avec les m�mes couleurs, la m�me �paisseur, mais dans une situation horizontale.

�J'ai observ� dans plus d'une montagne des couches ainsi retrouss�es, aupres desquelles on voit le vide qu'elles paroissent avoir laiss� en se repliant sur elles m�mes.

�Dans l'ober Hasli la vall�e de Meiringen au dessus du village de Stein.

�Dans le canton de Uri, sur le bords du lac de Lucerne, on en voit aussi plusieurs exemples bien distincts.

�Une montagne plus rapproch�e de notre cascade, et qui presente aussi ce ph�nom�ne, est situ�e derri�re elle au nord-est entre le village de Seiz et les granges des Fonds. Cette montagne porte le nom d'Anterne. Elle est plus �lev�e que celle du Nant d'Arpenaz, ses couches forment des arcs concentriques plus grands et plus recourb�s encore, et l'on voit de m�me � leur droite un vide qu'elles semblent avoir laiss� en se levant et se repliant sur la gauche.

�Mais malgr� ces observations, ce n'est pas sans peine que j'ai recours � ces agens presque sur-naturelles, sur-tout quand je n'aper�ois aucun de leurs vestiges; car cette montagne et celle d'alentour ne laissent apercevoir aucune trace du feu. Je laiss� donc cette question en suspens; j'y reviendrai plus d'une fois, et m�me avant la fin de ce chapitre.

�Il faut � present jetter un coup-d'oeil sur les montagnes de l'autre cot� de l'Arve.

�� 474. Vis-�-vis de la cascade de l'autre cot� de la rivi�re, on voit un chaine de montagnes extr�mement �lev�es, qui pr�sentent leurs escarpemens au dessus de Sallenche, et contre le Mont Blanc. Leurs couches descendent par cons�quent vers la vall�e du Reposoir, situ�e � leur pied au nord-ouest.

�Mais au pied des escarpemens de cette m�me chaine, on voit une rang�e de bases montagnes paralleles � sa direction, inclin�es en appui contre ses escarpemens et qui descendent en pente douce vers Sallenche; de m�me encore une fois qu'au mont Saleve.

�� 475. De la cascade jusques � St Martin, on voit fr�quemment � sa gauche des couches singuli�rement contourn�es, et toujours dans cette esp�ce de pierre calcaire brune que nous suivons depuis si long-tems. Quelques-unes de ces couches forment presqu'un cercle entier, les plus remarquables sont � une demi-lieue de la cascade. Elles repr�sentent des arcs dont les convexit�s se regardent � peu pr�s comme dans un X; mais avec des plans situes obliquement entre les deux convexit�s, et des couches planes et horizontales imm�diatement au-dessus de l'arc de la gauche.

�Ces diverses couches sont si bien suivies dans tous leurs contours, et si singuli�rement entrelac�es que j'ai peine � croire qu'elles ayent �t� form�es dans une situation horizontale, et qu'ensuite des bouleversemens leur ayent donn� ces positions bizarres.

�D�j� il faudroit supposer que ces bouleversemens se sont faits dans un tems ou ces couches �toient encore molles et parfaitement flexibles, car on n'y voit rien de rompu, leurs courbures, m�me les plus angulaires, sont absolument enti�res.

�Ensuite il faudroit, que ces couches, dans cet �tat de mollesse, eussent �t� froiss�es et contourn�es d'une maniere tout-�-fait �trange, et presqu'impossible � expliquer en d�tail. D'ailleurs des explosions souterraines rompent, d�chirent, et ne soul�vent pas avec le m�nagement qu'exigeroit la conservation de continuit� de toutes ces parties.

�La crystallization peut seul, � mon avis, rendre raison de ces bizarreries; nous voyons, comme je l'ai d�j� dit, des alb�tres form�s pour ainsi dire sous nos yeux par de vrayes crystallizations dans les crevasses, et dans les cavernes des montagnes, presenter des couches dans lesquelles on observe des jeux tout aussi singuliers[2].�

[Footnote 2: M. de Saussure would explain the various shape and contortions of strata upon the principles of crystallization; but surely he has not adverted to the distinction of crystallization as an operation giving form or shape, and as giving only solidity or hardness, which last, it is apprehended, is the only sense in which our author here considers crystallization, although, from the way in which he has employed this principle, it would seem that it is the figure which is to be explained by it. This conjecture is supported by the example of alabaster or stalactites, with which he compares the section of those mountains; for, in the example of implicated figures of the stalactite marble, similar to those of the present distorted strata, crystallization has nothing to do with that part of the figure which corresponds to the case now under consideration; it forms indeed certain figures of crystals in the mass by which also the configuration of some minute parts, affected by those crystals, is determined; but the figure of those alabasters, which is to be compared with the present subject, arises solely from the current of petrifying water along the surface of the mass. This mass, therefore, being formed by succession from that water, crystallising calcareous earth, and carrying colouring parts of other earth, gives an appearance of stratification to a figure which is absolutely inconsistent with stratification; an operation which is performed by depositing materials at the bottom of the sea, and which the marine bodies contained in some of the strata sufficiently attest.]

�Je ne repugnerois donc pas � croire que le rocher de la cascade a pu �tre form� dans la situation dans laquelle il se presente; si ce vuide � sa droite, ses couches qui, bien que suivies, montrent pourtant quelques ruptures dans les flexions un peu fortes, et ses grands bancs de cette pierre grise compacte, qui n'est point si sujette � ces formes bizarres, n'�stablissoient pas une difference sensible entr'elles et celles que nous venons examiner.�

It is impossible to be more impartial than M. de Saussure has proved himself to be on this occasion, or to reason more in the manner in which every philosopher ought to reason on all occasions.

But to see the full value of this author's impartiality, notwithstanding of his system, let us follow him in the second volume of Voyages dans les Alpes. It is in chap. XX. entitled, Poudingues de Valorsine, that we find the following description, with his reasoning upon that appearance.

�On voit la (page 99.) que la base de cette montagne est un vrai granit gris � grains m�diocres, et dont la structure n'a rien de distinct; mais au-dessus de ces granits on trouve des roches feuillet�es quartzeuses m�lang�es de mica et de feldspath genre moyenne entre le granit vein� et la roche feuillet�e ordinaire. Leurs couches courent du nord au sud, comme la vall�e de Valorsine, et font avec l'horizon un angle de 60 degr�s, en s'appuyant au couchant contre cette m�me vall�e. Ces roches continuent dans la m�me situation jusques � ce qu'apres une demi-heure de marche, on les perd de vue sous la verdure qui tapisse une petite plaine, situ�e au milieu des bois, et qui se nomme le plan des Cebianes.

�� 689. De-l�, en montant obliquement du cot� du sud, on rencontre de grands blocs d'un schiste gris ou de couleur de lie-de-vin, quelquefois m�me d'un violet decid�, qui renferment une grande quantite de cailloux �trangers, les uns angulaires, les autres arrondis, et de diff�rentes grosseurs, depuis celle d'un grain de sable jusqu'� celle de la t�te. Je fus curieux de voir ces poudingues dans leur lieu natal; je montai droit en haut pour y arriver; mais l� quel ne fut pas mon �tonnement de trouver leur couches dans une situation verticale!

�� 690. On comprendra sans peine la raison de cet �tonnement si l'on consider� qu'il est impossible que ces poudingues aient �t� form�es dans cette situation.

�Que des particules de la plus extr�me t�nuit�, suspendues dans un liquide, puissent s'agglutiner entr'elles et former des couches verticales, c'est ce que nous avons la preuve en fait dans les alb�tres, les agathes, et m�me dans les crystallizations artificielles. Mais qu'une pierre toute form�e, de la grosseur de la t�te, se soit arr�t�e au milieu d'une parois verticale, et ait attendu l� que les petites particules de la pierre vinssent l'envelopper, la souder et la fixer dans cette place, c'est une supposition absurde et impossible. Il faut donc regarder comme une chose d�montr�e, que ces poudingues ont �t� form�s dans une position horizontale, ou � peu-pr�s telle, et redress�s, ensuite apr�s leurs endurcissement. Quelle est la cause qui les a redress�s? c'est ce que nous ignorons encore; mais c'est d�j� un pas, et un pas important, au milieu de la quantit� prodigieuse de couches verticales que nous rencontrons dans nos Alpes, que d'en avoir trouv� quelques-unes dont on soit parfaitement s�r qu'elles ont �t� form�es dans une situation horizontale.

�� 691. La nature m�me de la mati�re qu'enveloppe les cailloux de ces poudingues rend ce fait plus curieux et plus d�cisif. Car si c'�toit une p�te informe et grossi�re, on pourroit croire que ces cailloux et la p�te qui les lie ont �t� jet�s p�le-m�le dans quelques crevasses verticales, o� la partie liquide c'est endurcie par le dess�chement. Mais bien loin de-l�, le tissu de cette p�te est d'une finesse admirables; c'est une schiste, dont les feuillets �l�mentaires sont excessivement minces, m�l�s de mica, et parfaitement parall�les aux plans qui divisent les couches de la pierre. Ces couches m�mes sont tr�s-r�guli�res, bien suives et de diff�rentes �paisseurs, depuis une demi pouce jusques � plusieurs pieds. Celles qui sont minces contiennent peu et quelquefois point de cailloux �trangers, et on observe quelques alternatives de ces couches minces sans cailloux et des couches �paisses qui en contiennent. La couleur du fond de ce schiste varie beaucoup; il est ici gris, l� verd�tre, le plus souvent violet ou rouge�tre; on en voit aussi qui est marbr� de ces diff�rentes couleurs. Ses couches sont dirig�es du nord au sud exactement comme celles des roches granito�des qui sont au-dessous, � 688. mais l'inclinaison du schiste est beaucoup plus grande, ses couches sont souvent tout-�-fait verticales, et lorsqu'elles ne le sont pas, elles montent de quelques degr�s du m�me cot� que les roches dont je viens de parler; c'est-�-dire, du cot� de l'ouest.

�� 692. Les cailloux enclav�s dans ce schiste sont, comme je l'ai dite, de diff�rentes grandeurs, depuis celle du grain de sable, jusques � 6 ou 7 pouces de diam�tre; ils appartiennent tous � la classe des roches que j'appelle primitives; je n'y ai cependant pas vu de granit en masse; seulement des granits feuillet�s, des roches feuillet�es, m�lang�es de quartz et de mica; des fragmens m�me de quartz pur; mais absolument aucun schiste purement argileux, ni aucune pierre calcaire, rien qui f�t effervescence avec l'eau-forte, et la p�te m�me qui renferme ces cailloux n'en fait aucune. Leur forme varie; les uns sont arrondis et ont manifestement perdu leurs angles par le frottement; d'autres ont tous leurs angles vifs, quelques uns m�me ont la forme rhombo�dale qu'affectent si fr�quemment les roches de ce genre. Dans les parties de la pierre ou ces cailloux �trangers sont entass�s en tr�s-grand nombre, les �l�mens du schiste n'ont pas eu la libert� de s'arranger et de former des feuillets parall�les; mais par-tout o� les cailloux laissent entr'eux des intervalles sensibles, les feuillets reparoissent, et sont constamment paralleles, et entr'eux et aux plans qui divisent les couches.

�� 693. Les bancs de ces schistes poudingues forment dans la montagne une �paisseur d'environ cent toises, compt�es de l'est � l'ouest transversalement aux couches, et je l'ai suivie dans le sens de la longueur l'espace de plus d'une lieue; on ne peut pas la suivre plus long-temps, parce que les bancs se cachent et s'enfoncent sous la terre.�

Here M. de Saussure, who is always more anxious to establish truth, than preserve theory, gives up the formation of the alpine strata by crystallization. Let us now see how he acknowledges the evidence of softness in those strata. It is in his description of the Val de Mont Joye, Tom. 2d. page 173.

�Ce sont des roches dures � fond de quartz, ou de feldspath blanc, confus�ment cristallis�, avec des veines noires de mica ou de schorl en petites lames. Ces veines, qui p�n�trent tout au travers de la pierre, sont la section des couches dont elle est compos�e; on les voit, ici planes et parall�les, entr'elles; la en zig-zags, renferm�s entre de plans parfaitement parall�les; accident dont les �toffes tout-�-la-fois ray�es et chin�es donnent encore le dessin. Ces anfractuosit�s des couches sont-elles un effect de la crystallization, ou bien d'un mouvement de pression qui a refoul� des couches planes lorsqu'elles �toient encore flexibles, apr�s quoi d'autres couches planes sont venues se former sur elles.�

M. de Saussure has no idea of strata formed at the bottom of the sea, being afterwards softened by means of heat and fusion. He had already given up the supposition of those vertical or highly inclined strata having been formed in their present position; but had this geologist seen that it was the same cause by which those strata had both been raised in their place and softened in their substance, I am persuaded that he would have freely acknowledged, in this zig-zag shape, which is so common in the alpine strata, the fullest evidence of the softening and the elevating power.

At the Tour de Fols, near St Bernard, M. de Saussure found an appearance the most distinct of its kind, and worthy to be recorded as a leading fact in matters of geology. Voyages dans les Alpes, Tome 2d. pag. 454.

�La direction g�n�ral des couches de ces rochers et des ardoises qui les s�parent, est donc du midi au nord, ou plus exactement du sud-sud-ouest au nord-nord-est; mais cette direction est coup�e � angles droits par des couches d'ardoises et de feuillet quartzeux, qui passent du levant au couchant par le milieu des couches qui courent du midi au nord.�

Clearly as this fact must demonstrate, to a reasoning person, the fracture and dislocation of strata, our author, who knows so well the reasoning of naturalists on such an occasion, gives us his opinion as follows: �Quant � la raison de ce fait, on peut l'attribuer � de boulversemens, et c'est ce qui me paro�t le plus vraisemblable. On pourroit cependant supposer qu'il existoit au milieu de ces couches une grande fissure, qui a �t� remplie par des couches transversales. Mais il faudroit pour cela que ce remplissage se f�t fait dans le temps m�me de la formation de ce montagne, puisque les ardoises et les pyramides quartzeuses, donc la direction est transversales, sont pr�cis�ment de la m�me nature que les autres; et il faudrait encore supposer, qu'elles ont �t� form�es dans la situation tr�s-inclin�e qu'on leur voit aujourd'hui; supposition que l'on aura quelque peine � admettre.�

In this second volume, M. de Saussure gives us a general view with regard to the mountains which border the valley of the Rh�ne, p. 543.

�� 1095. Cette suite de montagnes calcaire que nous avons c�toy�e depuis St Maurice jusques � Chillon, ne presente presque nulle part des couches r�guli�res et horizontales: elles sont presque par-tout inclin�es, fl�chies, et paroissent avoir �t� tourment�es par des causes violentes: car de simples affaissemens ne suffisent pas � mon gr� pour rendre raison de toutes leurs formes. Leurs escarpemens sont aussi assez irr�guli�rement situ�s; la plus grande partie d'entr'eux paro�t cependant tourn�e du c�t� de la vall�e du Rh�ne.

�La suite des montagnes qui correspond � celle-ci sur la rive gauche du Rh�ne et du lac est aussi calcaire, et �-peu-pres aussi irr�guli�re. La plupart de ces montagnes, celles surtout qui sont les plus voisines du lac, sont escarp�es, et du cot� du lac et de celui du Rh�ne. Les vall�es qui les s�parent paroissent les diviser en cha�nes paralleles au lac, qui courent du nord-est au sud-ouest. Les plus voisines du lac sont escarp�es contre lui, comme je viens de le dire, tandis que les plus �loign�es du lac, ou les plus proches du centre des Alpes, sont inclin�es contre ces m�mes Alpes. Le Val de lie s�pare ces deux ordres de montagnes: cette vall�e riche et fertile a la forme d'un berceau; les deux cha�nes qui la bordent s'�l�vent en pente douce de son c�t�, et tournent leurs escarpemens, l'une contre le lac, l'autre contre les Alpes; au reste je n'ai point parcouru ces montagnes, je n'ai pu en juger qu'en les observant de loin.

�Mais ce dont on peut �tre certain, c'est que, si les montagnes qui bordent ces deux rives de la vall�e du Rh�ne, se ressemblent par leur nature, qui est calcaire de part et d'autre elles ne se ressemblent point par leur structure. On n'y voit aucune correspondance, ni dans les positions, ni dans les formes: Les vall�es qui les s�parent ne se correspondent pas non plus. Ce d�faut de correspondance me paro�t encore r�veiller l'id�e des bouleversemens.�

The general result, from these observations of our author, is this. First, there is no distinction to be made of what is termed primary and secondary mountains, with regard to the position of their strata; every different species of stratum, from the stratified granite and quartzy schistus of the Alps to the oolites of the Jura and Saleve, being found in every respect the same; whether this shall be supposed as arising from their original formation, or, according to the present theory, from a subsequent deplacement of strata formed originally in a horizontal situation.

Secondly, it appears that, in all those alpine regions, the vertical position of strata prevails; and that this appearance, which seems to be as general in the alpine regions of the globe as it is here in the mountainous regions of the Alps, has been brought about both by the fracture and flexure of those masses, which, if properly strata, must have been originally extended in planes nearly horizontal. Whereas, in descending from that mountainous region towards the more level country of France, the same changes in the natural position of strata are observed, with this difference, that here they are in a less degree. Now that those vertical strata had been originally formed at the bottom of the sea is evident from this author's observation, which has been already referred to (vol. 1st, page 23).

Thirdly, in all those accurate observations of a naturalist, so well qualified for this purpose, there appears nothing but what is perfectly consistent with such a cause as had operated by slow degrees, and softened the bodies of rocks at the same time that it bended them into shapes and positions inconsistent with their original formation, and often almost diametrically opposite to it; although there appeared to our author an insurmountable difficulty in ascribing those changes to the operation of subterranean fire, according to the idea hitherto conceived of that agent.

This grand mineral view of so large a tract of country is the more interesting, in that there has not occurred the least appearance of volcanic matter, nor basaltic rock, in all that space, where so great manifestation is made of those internal operations of the globe by which strata had been consolidated in their substance, and erected into positions the most distant from that in which they had been formed.

It is peculiarly satisfactory to me, and I hope also to my readers, to have the observations of so able a philosopher and so diligent a naturalist to offer in confirmation of a theory which had been formed from appearances of the same kind in a country so far distant from those of our author now described, as are the Alps of Savoy from those of Scotland. It gives me a singular pleasure, in thus collecting facts for the support of my opinion, to contribute all I can to recommend the study of a work in natural history the most exemplary of its kind; and a work which will remain the unalterable conveyance of precious information when theories making a temporary figure may be changed.

To a person who understands the present theory, there can be no occasion here to give the particular applications which will naturally occur in reading those various descriptions. In these examples are contained every species of bending, twisting, and displacement of the strata, from the horizontal state in which they had been originally formed to the vertical, or even to their being doubled back; and although M. de Saussure had endeavoured to reason himself into a belief of those inverted strata having been formed in their present place, it is evident that he had only founded this opinion upon a principle which, however just, may here perhaps be found misplaced; it is that of not endeavouring to explain appearances from any supposition of which we have not full conviction. I flatter myself, that when he shall have considered the arguments which have here been employed for the manifold, the general operations of subterranean fire, as well as for the long continued operations of water on the surface of the erected land, he will not seek after any other explanation than that which had naturally occurred to himself upon the occasion, and which he most ingenuously declares to have great weight, although not sufficient to persuade him of its truth.

The same Subject continued, with examples from different Countries.

Our theory, it must be remembered, has for principle, that all the alpine as well as horizontal strata had their origin at the bottom of the sea, from the deposits of sand, gravel, calcareous and other bodies, the materials of the land which was then going into ruin; it must also be observed, that all those strata of various materials, although originally uniform in their structure and appearance as a collection of stratified materials, have acquired appearances which often are difficult to reconcile with that of their original, and is only to be understood by an examination of a series in those objects, or that gradation which is sometimes to be perceived from the one extreme state to the other, that is from their natural to their most changed state. M. de Saussure who will not be suspected of having any such theory in his view, will be found giving the most exemplary confirmation to that system of things.

I would therefore beg leave farther to transcribe what he has observed most interesting with regard to that gradation of changed strata. It is in the high passage of the Bon-Homme, tom. 2. p. 179.

�Depuis le col, dont je viens de parler, jusqu'a la croix, qui suivant l'usage, est plac�e au point le plus �lev� du passage, on a trois quarts de lieue, ou une petite heure de route, dans laquelle on traverse des gr�s, des br�ches calcaires, des pierres calcaires simples de couleur grise, d'autres calcaires bleu�tres et des ardoises: ces alternatives se r�p�tent � plusieurs reprises. Parmi ces gr�s on en trouve qui renferment des cailloux roul�s, et qui font effervescence avec les acides; d'autres qui ne renferment point de cailloux, et qui ne font point d'effervescence.

�Quelques-uns de ces gr�s m'out paru remarquables par leur ressemblance avec des roches feuillet�es; ils sont compactes m�l�s de mica; un suc quartzeux remplit tous les interstices de leurs grains, et leur donne une duret� et une solidit� singuliers; il n'y a personne, qui en voyant des morceaux d�tach�s de cette pierre, ne la pr�t pour une roche feuillet�e; mais quand on la trouve dans le lieu de sa formation, et qu'on voit les gradations qui la lient avec des gr�s indubitables, par exemple avec ceux qui renferment des cailloux roul�s, on ne peut plus douter de sa nature. Ces couches sont en g�n�ral inclin�es de 30 degr�s en descendant au sud-est.�

Our author would here make a distinction of the roche feuillet�e and the gr�s; the one he considers as primitive, and as having had an origin of which we are extremely ignorant; the other he considers as a secondary thing, and as having been formed of sand deposited at the bottom of moving water, and afterwards becoming stone. This great resemblance, therefore, of those two things so different in the opinion of naturalists, struck him in that forcible manner. Nothing can be a stronger confirmation of the present theory, which gives a similar origin to those two different things, than is the observation of so good a naturalist, finding those two things in a manner undistinguishable.

He thus proceeds: �J'ai vu dans les Vosges de tr�s-beaux gr�s du m�me genre; ils ne ressembloient cependant pas autant � des roches primitives, parce qu'ils ne contenoient pas de mica. Mais ce qu'il y a ici de plus digne d'attention, et que l'on ne voit point dans les Vosges, c'est de trouver des gr�s de cette nature renferm�s entre des bancs de pierre calcaire. Cependant plus ces gr�s s'�loignent de la roche primitive, qui forme la base de la montagne, et moins ils sont solides et quartzeux jusqu'� ce qu'enfin les plus �lev�s font effervescence avec l'eau-forte.�

Here again the alpine lime-stones, which, according to the present naturalists, should be primitive, are plainly homologated in their origin with strata formed of sand.

Our author proceeds, (p. 181,) � 765, �Le haut du passage du Bon-Homme, au pied de la croix est d'ardoises minces m�l�es de feuillets de quartz. En descendant au Chapiu, on trouve ces m�mes ardoises alternant avec des couches de gr�s mince feuillet�, m�l� de mica, puis des calcaires simples, puis des br�ches calcaires qui renferment des fragmens calcaires � angles vifs. Toutes ces couches descendent au sud-est suivant la pente de la montagne, mais avec un peu plus de rapidit�.

�Comme cette montagne est absolument d�garnie d'arbres, on y voit d'un coup-d'oeil les progr�s de l'action des eaux. Des sillons � peine visibles dans le haut, s'�largissent et s'approfondissent graduellement vers le bas, o� ils forment enfin des ravines profondes, que l'on pourrait presque nommer des vall�es. Ces sillons ramifies sur toute la pente de la montagne et remplis encore de neige, tandis que leurs intervalles sont couverts de gazon, forment sur ce fond verd une broderie blanche, dont l'effet est extr�mement singulier. Lorsque je passai l�, le 13 Juillet 1774, tous les enfoncemens de ces neiges �toient couverts de la poudre rouge que j'ai d�crite � 646.

�Vers la bas de la descente, on trouve des chalets que je m'�tonnai de voir construits en pierres de taille, d'une forme tr�s r�guli�re; je demandai la raison de cette recherche, peu commune dans les montagnes, et j'appris que c'�toit la nature qui avoit fait tous les frais de cette taille. Effectivement je trouvai un peu plus bas une profonde ravine, creus�e par les eaux dans des couches d'un beau gr�s qui se divise de lui-m�me, et que l'on voit dans sa position originelle actuellement divise en grands parall�l�pip�des rectangles. Est-ce une retraite op�r�e par le dess�chement, ou n'est-ce pas plut�t l'affaissement successif des couches qui les a divis�es de cette mani�re? C'est ce que je ne d�ciderai pas dans ce cas particulier.�

The only thing which, in this particular case, makes our author express his wonder, is the extreme regularity of these natural divisions of stone; for, the same appearances are to be found in every case of consolidated strata, though not always with such extreme regularity. But this is one of the most irrefragable arguments for those various bodies having been consolidated by means of heat and fusion. The contraction of the mass, consolidated by fusion or the effect of fire, is the cause of those natural divisions in the strata; and the regularity, which is always to be observed more or less, depends upon the proper circumstances of the case, and the uniform nature of the mass.

(Page 184.) �Le matin avant de partir du Chapiu, j'allai voir si les beaux gr�s rectangulaires, que j'avois observ�s la veille descendoient jusqu'au bas de la montagne; j'y trouvai effectivement des gr�s mais � couches minces, et qui ne se divisoient point avec r�gularit�; en revanche, je vis des couches de ce gr�s ploy�es et reploy�es en zig-zags, comme celles que j'avois rencontr�es aux contamines, � 755, et ces couches ond�es �toient aussi renferm�es entre de couches planes et parall�les. Ce ph�nom�ne est bien plus rare dans les gr�s, que dans les roches feuillet�es proprement dites.�

Thus every appearance is found by which the primitive schisti are perfectly resembled, both as to their original formation and their accidents, with the strata, which are acknowledged by naturalists as being the common operation of the sea.

Our author then gives an account of the Passage de Fours, in which he makes the following observations:

�� 776. Tout pr�s du sommet du Col, on rencontre de beaux bancs de gr�s jaun�tre qui sortent de dessous la pierre calcaire, et qui pourtant ne font aucune effervescence avec les acides.

�� 777. Je mis deux heures et trois quarts � monter depuis le hameau du Glacier jusqu'au haut du Col, d'o� l'on descend � la croix du Bon-Homme. J'envoyai mes mulets m'attendre � cette croix, et je m'acheminai avec Pierre Balme sur ma droite, pour atteindre le faite de la montagne dont la cime arrondie me paroissoit devoir dominer sur toutes les montagnes d'alentour. J'ai donn� � cette sommit�, qui n'avoit point de nom, celui de Cime des Fours, � cause du passage qu'elle domine. De grandes plaques de neige couvroient en divers endroits la route que j'avois � faire pour y aller; le roc se montroit cependant assez pour que l'on p�t reconno�tre sa nature.

�� 778. Je traversai d'abord des couches des gr�s qui �toient la continuation de celles dont je viens de parler, � 776. Je trouvai ensuite des bancs d'une esp�ce de poudingue grossier, dont le fond �toit ce m�me gr�s rempli de cailloux arrondis. Quelques uns de ces bancs se sont d�compos�s, et les eaux out entra�n� les parties de sable qui lioient les cailloux, en sorte que ceux-ci sont demeur�s libres et entass�s exactement comme au bord d'un lac ou d'une rivi�re. Il �toit si �trange de marcher � cette hauteur sur des cailloux roul�s, que Pierre Balme en t�moigna son �tonnement, m�me avant, que j'en parlasse. On auroit �t� tent� de croire qu'une cascade tombant anciennement de quelque rocher plus �lev�, d�truit d�s-lors par le temps, avoit arrondi ces cailloux, si on n'en trouvoit pas de semblables encore enclav�s dans les couches r�guli�res du gr�s qui compose le haut de cette montagne.

�� 779. Quoique depuis long-temps je ne doute plus que les eaux n'aient couvert et m�me form� ces montagnes, et qu'il y en ait m�me des preuves plus fortes que l'existence de ces cailloux roul�s, cependant leur accumulation sur cette cime avoit quelque chose de si extraordinaire, et qui parloit aux sens un langage si persuasif, que je ne pouvois pas revenir de mon �tonnement. Si en marchant sur ces cailloux, et en les observant, j'oubliois pour un moment le lieu o� j'�tois, je me croyois au bord de notre lac; mais, pour peu que mes yeux s'�cartassent � droite ou � gauche, je voyois au-dessous de moi des profondeurs immenses; et ce contraste avoit quelque chose qui tenoit d'un r�ve; je me repr�sentois alors avec une extr�me vivacit� les eaux remplissant toutes ces profondeurs, et venant battre et arrondir � mes pieds ces cailloux sur lesquels je marchois, tandis que les hautes aiguilles formoient seules des isles au-dessus de cette mer immense; je me demandois ensuite quand et comment ces eaux s'�toient retir�es. Mais il fallut m'arracher � ces grandes sp�culations et employer plus utilement mon temps � l'exacte observation de ces singuliers ph�nom�nes.�

The fact here worthy of observation is the effect of time in decomposing this gr�s, or sand-stone, which contains the gravel. All the other appearances follow naturally from the situation of this place, which is a summit, and does not allow of such a collection of water as might travel or transport the loose gravel, although it has been sufficient for carrying away the sand. This decomposition of the sand stone we shall find also explained from what follows of the description of this place.

�� 780. Tous les bancs de gr�s que l'on voit sur cette montagne ne renferment pas des cailloux roul�s; il y a des alternatives irr�guli�res, de bancs de gr�s pur, et de bancs de gr�s m�l� de cailloux. Les plus �lev�s n'en contiennent point. Le plus haut de ceux qui en renferment est un banc bien suivi d'un pied d'�paisseur, et qui monte de 30 degr�s au nord-nord-ouest.

�Quelques-uns de ces bancs, remplis de cailloux, offrent une particularit� bien remarquable; on voit � leur surface ext�rieure, expos�e � l'air, une esp�ce de r�seau form� par des veines noires solides, et saillantes de deux ou trois pouces au-dessus de la surface de la pierre; les mailles de ce r�seau sont quelquefois irr�gulieres, mais ce sont pour la plupart des quadrilat�res obliquangles, dont les c�t�s ont huit � dix pouces de longueur. Comme ces pierres ont toutes un tendance � se partager en rhombo�des, il paro�t qu'il y a eu anciennement des fentes qui divisoient les bancs en parties de cette forme; et que ces fentes ont �t� remplies par du sable qui a �t� ciment� par un suc ferrugineux; ce gluten solide a rendu ces parties plus dures que le reste de la pierre; et lorsque les injures de l'air ont rong� la surface de ces bancs, les mailles du r�seau sont demeur�es saillantes.

�Les cailloux arrondis, qui out �t� long-temps expos�s � l'air, out aussi pris par dehors une teinte noir�tre ferrugineuse, mais ceux qui sont encore renferm�s dans les bancs de gr�s ont comme lui une couleur jaun�tre. Je n'en trouvai l� aucun qui ne fut de nature primitive, et la plupart �toient de feldspath gris ou roux tr�s-dur, et confus�ment crystallis�. Ce sont donc des pierres qui n'ont point naturellement une forme arrondie; et qui, par cons�quent, ne tiennent celle qu'elles ont ici, que du roulement, et du frottement des eaux.

�Tous ces gr�s font effervescence avec l'eau-forte, mais les parties du r�seau ferrugineux en font beaucoup moins que le fond m�me du gr�s. De m�me si l'on compare entr'eux les gr�s qui renferment des cailloux avec ceux qui n'en contiennent pas, on trouve dans ceux-ci plus de gluten calcaire, l'eau-forte diminue beaucoup plus leur coh�rence.

�Sur la cime m�me de la montagne, ces gr�s sont recouverts par une ardoise grise, luisante, qui s'exfolie � l'air. Et si l'on redescend de cette m�me cime par le nord-est, du c�t� oppos� au passage des Fours, on retrouvera des bancs d'un gr�s parfaitement semblable, et qui se divisent l� d'eux-m�mes en petits fragmens parall�l�pip�des.

�Du haut de cette cime, �lev�e de 1396 toises au-dessus de la mer, on a une vue tr�s entendue. Au nord et au nord-ouest les vall�es de Mont Joie, de Passy, de Sallanches; au couchant la haut cime calcaire dont j'ai parl�, � 759; au sud les montagnes qui s'�tendent depuis le Chapiu jusqu'au Col de la Seigne; � l'est, ce m�me Col que l'on domine beaucoup. Sur la droite de ce col, on voit du c�t� de l'Italie la cha�ne du Cramont, et plusieurs autres cha�nes qui lui sont parall�les, tourner tous leurs escarpemens contre la cha�ne centrale, de m�me qu'on voit du c�te de la Savoye, les cha�nes du Reposoir, de Passy, de Servoz, tourner en sens contraire leurs escarpemens contre cette m�me cha�ne. Car c'est-la une des vues tr�s �tendues sur les deux cot�s oppos�s des Alpes; puisque l'on d�couvre d'ici les montagnes de Courmayeur et de l'All�e Blanche, qui sont du c�t� m�ridional de la chaine, et celles du Faucigny et de la Tarentaise, qui sont du c�t� septentrional. Or les sites d'ou l'on jouit tout �-la-fois de ces deux aspects sont tr�s rares; parce que les hautes cimes de la cha�ne centrale sont presque toutes inaccessibles, et les cols par lesquels on la traverse sont presque tous tortueux, �troite, et ne pr�sentent pour la plupart que de vues tr�s born�es.�

We have here two facts extremely important with regard to the present theory. The one of these respects the original formation of those alpine strata; the other the elevation of those strata from the bottom of the sea, and particularly the erection of those bodies, which had been formed horizontal, to their present state, which is that of being extremely inclined. It is to this last, that I would now particularly call the attention of my readers.

It is rarely that such an observation as this is to be met with. Perhaps it is rarely that this great fact occurs in nature, that is, so as to be a thing perceptible; it is still more rare that a person capable of making the observation has had the opportunity of perceiving it; and it is fortunate for the present theory, that our author, without prejudice or the bias of system, had been led, in the accuracy of a general examination, to make an observation which, I believe, will hardly correspond with any other theory but the present.

If strata are to be erected from the horizontal towards the vertical position, a subterraneous power must be placed under those strata; and this operation must affect those consolidated bodies with a certain degree of regularity, which however, from many interfering circumstances, may be seldom the object of our observation. If indeed we are to confine this subterraneous operation to a little spot, the effect may be very distinctly perceived in one view; such are those strata elevated like the roof of a house, which M. de Saussure has also described. But when the operation of this cause is to be extended to a great country, as that of the Alps, it is not easy to comprehend, as it were, in one view, the various corresponding effects of the same cause, through a space of country so extensive, and where so many different and confounding observations must be made. In this case, we must generalize the particular observations, with regard to the inclinations of strata and their direction, in order to find a similar effect prevailing among bodies thus changed according to a certain rule; this rule then directs our understanding of the cause. The general direction of those alpine strata, in this place, is to run S.E. and N.W. that is to say, this is the horizontal line of those inclined beds. We also find that there is a middle line of inclination for those erected strata in this alpine region; as if this line had been the focus or centre of action and elevation, the strata on each side being elevated towards this lint, and declined from it by descending in the opposite direction.

The view which our author has now given us from this mountain is a most interesting object, and it is a beautiful illustration of this theory; for, the breaking of the tops of mountains, composed of erected strata, must be on that side to which their strata rise; and this rupture being here towards the central line of greatest elevation, the ridges must in their breaking generally respect the central ridge. But this is the very view which our enlightened observator has taken of the subject; and it is confirmed in still extending our observations westward through the kingdom of France, where we find the ridges of the Jura, and then those of Burgundy gradually diminishing in their height as they recede from the centre of elevation, but still preserving a certain degree of regularity in the course of their direction.

But our author has still further observed that this is a general rule with regard to mountains. I will give it in his own words, Tom. 2. (p. 338.)

�� 918. Mais la cha�ne centrale n'est pas la seule primitive qu'il y ait de ce c�t� des Alpes. Du haut du Cramont en se tournant du c�t� de I'Italie, on voit un entassement de montagnes qui s'�tendent aussi loin que peut aller la vue. Parmi ces montagnes on en distingue un au sud-ouest qui est extr�mement �lev�e: son nom est Ruitor: elle se pr�sente au Cramont �-peu-pr�s pr�s sous le m�me aspect que le Mont-Blanc � Gen�ve; sa cime est couverte de neiges, un grand glacier descend de sa moyenne r�gion, et il en sort un torrent qui vient se jetter dans la riviere de la Tuile. Cette haut montagne, de nature primitive, est au centre d'une cha�ne de montagnes moins �lev�es, mais primitives comme elle, et qui passent au-dessus du val de Cogne. On voit de la cime du Cramont des montagnes secondaires situ�es entre le Cramont et cette cha�ne primitive, et on reconno�t que les couches de ces montagnes s'�l�vent contre cette cha�ne en tournant le dos � la cha�ne centrale.

�� 939. L'inclinaison du Cramont et de la cha�ne contre le Mont-Blanc, n'est donc pas un ph�nom�ne qui n'appartienne qu'� cette seule montagne; il est commun � toutes les montagnes primitives, dont c'est une loi g�n�rale que les secondaires qui les bordent, ont de part et d'autre leurs couches ascendantes vers elles. C'est sur le Cramont, que je fis pour la premi�re fois, cette observation alors nouvelle, que j'ai verifi� ensuite sur un grand nombre d'autres montagnes, non pas seulement dans la cha�ne des Alpes, mais encore dans diverses autres cha�nes, comme je le ferai voir dans le IVe. volume. Les preuves multipli�es que j'en avois sous les yeux au moment o� je l'eus faite, et d'autres analogues que ma m�moire me rappela d'abord, me firent soup�onner son universalit�, et je la liai imm�diatement aux observations que je venois de faire sur la structure du Mont-Blanc et de la cha�ne primitive dont il fait partie. Je voyois cette cha�ne compos�e de feuillets que l'on pouvoit consid�rer comme des couches; je voyois ces couches verticales dans le centre de cette cha�ne et celles des secondaires presque verticales dans le point de leur contact avec elles, le devenir moins � de plus grandes distances, et s'approcher peu-�-peu de la situation horizontale � mesure qu'elles s'�loignoient de leur point d'appui. Je voyois ainsi les nuances entre les primitives et les secondaires, que j'avois d�j� observ�es dans la mati�re dont elles sont compos�es, s'�tendre aussi � la forme et � la situation de leurs couches; puisque les sommit�s secondaires que j'avois l� sous les yeux se terminoient en lames piramidales aigues et tranchantes, tout comme le Mont-Blanc, et les montagnes primitives de la cha�ne. Je conclus de tout ces rapports, que, puisque les montagnes secondaires avoient �t� form�es dans le sein des eaux, il falloit que les primitives eussent aussi la m�me origine. Retra�ant alors dans ma t�te la suite des grandes r�volutions qu'a subies notre globe, je vis la mer, couvrant jadis toute la surface du globe, former par des d�p�ts et des crystallisations successives, d'abord les montagnes primitives puis les secondaires; je vis ces mati�res s'arranger horizontalement par couches concentriques; et ensuite le feu ou d'autres fluides �lastiques renfermes dans l'int�rieur du globe, soulever et rompre cette �corce, et faire sortir ainsi la partie int�rieure et primitive de cette m�me �corce, tandis que ses parties ext�rieures ou secondaires demeuroient appuy�es contre les couches int�rieures. Je vis ensuite les eaux se pr�cipiter dans les gouffres crev�s et vides par l'explosion des fluides �lastiques; et ces eaux, en courant � ces gouffres, entra�ner � de grandes distances ces blocs �normes que nous trouvons �pars dans nos plaines. Je vis enfin apr�s la retraite des eaux les germes des plantes et des animaux, f�cond�s par l'air nouvellement produit, commencer � se d�velopper, et sur la terre abandonn�e par les eaux, et dans les eaux m�mes, qui s'arr�t�rent dans les cavit�s de la surface.

�Telles font les pens�es que ces observations nouvelles m'inspir�rent en 1774. On verra dans le IVe. volume comment douze ou treize ans d'observations et de r�flections continuelles sur ce m�me sujet auront modifi� ce premier germe de mes conjectures; je n'en parle ici qu'historiquement, et pour faire voir qu'elles sont les premi�res id�es que le grande spectacle du Cramont doit naturellement faire �clore dans une t�te qui n'a encore �pous� aucun syst�me.�

How far these appearances, which had suggested to this philosopher those ideas, agree with or confirm the present theory, which had been founded upon other observations, is here submitted to the learned.

We have now not only found a cause corresponding to that which can alone be conceived as producing this evident deplacement of bodies formed horizontally at the bottom of the sea, but we have also found that this same cause has operated every where upon those strata, in consolidating by means of fusion the porous texture of their masses. Now when the evidence of those two facts are united, we cannot refuse to admit, as a part of the general system of the earth, that which is every where to be observed, although not every where to such advantage as in those regular appearances, which our author has now described from those alpine regions.

I have only one more example to give concerning this great region of the Alps belonging to Savoy and Switzerland. It is from the author of Les Tableaux de la Suisse.

[3] �On s'embarque � Fluelen � une demi-lieue d'Altorf sur le lac des quatre Waldstoett ou cantons forestiers; les bords de ce lac sont des rochers souvent � pic et d'une tr�s grande �l�vation et la profondeur de ses eaux proportionn�e. Ces roches sont toutes calcaires, et souvent remarquables par la position singuli�re de leurs couches. A une demi-lieue environ de Fluelen, sur la droite, des couches de six pouces environ d'�paisseur sont d�pos�es en zig-zags comme une tapisserie de point-d'hongrie; � une lieue et demie � c�t� de couches bien horizontales, de quatre � cinq pieds d'�paisseur il y en a de contourn�es de forme circulaire et d'elliptiques. Il seroit difficile de se faire une id�e de la formation de pareilles couches, et d'expliquer comment les eaux ont pu les deposer ainsi.�

[Footnote 3: Discours sur l'Hist. Nat. de la Suisse, page CLV.]

Having thus given a view of a large tract of country where the strata are indurated or consolidated and extremely elevated, without the least appearance of subterraneous fire or volcanic productions, it will now be proper to compare with this another tract of country, where the strata, though not erected to that extreme degree, have nevertheless been evidently elevated, and, which is principally to the present purpose, are superincumbent upon immense beds of basaltes or subterranean lava. This mineral view is now to be taken from M. de Luc, Lettres Phisiques et Morales, Tom. 4.

This naturalist had discovered along the side of the Rhine many ancient volcanos which have been long extinct; but that is no part of the subject which we now inquire after; we want to see the operations of subterraneous lava which this author has actually exposed to our view without having seen it in that light himself. He would persuade us, as he has done himself, that there had been in the ancient sea volcanic eruptions under water which formed basaltic rocks; and that those eruptions had been afterwards covered with strata formed by the deposits made in that sea; which strata are now found in the natural position in which they had been formed, the sea having retreated into the bowels of the earth, and left those calcareous and arenaceous strata, with the volcanic productions upon which they had been deposited, in the atmosphere.

It would be out of place here to examine the explanation which this author has given with regard to the consolidation of those deposited strata which is by means of the filtration of water, but as in this place there occurs some unusual or curious examples of a particular consolidation of limestone or calcareous deposits, as well as similar consolidations of the siliceous sort, it may be worth while to mention them in their place that so we may see the connection of those things, and give all the means of information which the extremely attentive observations of this naturalist has furnished to the world of letters.

At Oberwinter our author remarks a stratum of consolidated sand above volcanic matter, Tome 4, p. 162. �Tant que j'ai parcouru le pied du c�ne, je n'ai vu qu'un terrain compos� de ces d�bris, et cultiv� en vignes. Mais apr�s l'avoir d�pass�, j'ai trouv� la coupe verticale d'une colline � couches pierreuses, si r�guliers, que je les ai prises au premier coup d'oeil pour de la pierre � chaux. L'esprit de nitre m'a d�tromp�: c'est une pierre sableuse tr�s compacte, dont les couches, qui n'ont souvent que quelques pouces d'�paisseur, s'�l�vent par une pente insensible vers le c�ne volcanique qu'elle recouvrent de ce cot� l� sans aucune apparence de d�sordre. Ces couches qui sont visiblement des d�p�ts de la mer, quoique je n'y ai pas trouv� de corps marins, ont �t� form�es depuis que le c�ne s'�toit �lev�.�

This is a species of reasoning which this acute naturalist would surely not have let pass in any other cosmologist. But here the love of system, or a particular theory, seems to have warped his judgment. For, had our author been treating of beds or bodies deposited in water, and preserving the natural situation in which they had been formed, he would have had reason to conclude that the superior bed was of the latest formation; but here is no question of superincumbent strata; it is a stratum which is superincumbent on a lava; and it is equally natural to suppose the lava posterior to the stratum as the stratum posterior to the lava.

Our author meets with a limestone too much erected in its position to be supposed as in its natural place, and then he explains this phenomenon in the following manner, p. 333. �Les rochers d'Ehrentbreitstein et de Lahnstein sont donc des faits particuliers. Ces rochers l� ont �t� formes par des d�p�ts de la mer: Les corps marin qu'ils renferment en font foi. D�s lors ils ont d� avoir dans leur origine la seule position que la mer p�t leur donner; l'horizontale ou l�g�rement inclin�e. Leur couches sont aujourd'hui rompues, et leur inclination n'est plus celle de d�p�ts imm�diats de la mer. Les collines, auxquelles elle appartenoient, sont en m�me tems entour�es de volcans anciens; et il est naturel d'en conclure, que c'est � eux que ces grands rochers doivent leur position actuelle.�

Here one would expect our author is to allow that volcanos may erect rocks in heightening them in their place; but this is not the light in which it has been seen by him, as will appear from what follows. �L'enfoncement d'une de leurs cot�s n'est rien, quand on consid�re le prodigieuse excavation qui ont d� se faire, pour porter au dehors toutes les montagnes, les collines, et les plaines volcaniques qui se trouvent dans ce vaste circuit.�

When a small portion of a stratum is examined, such as the present case, it is impossible from inspection to determine, whether it owes its inclined position to the sinking or the raising of the ground; the stratum is changed from its original position, but whether this has been brought about by the raising of the one side, or the sinking of the other is not apparent from what then is seen. But unless we are to explain the appearance of strata above the level of the sea by a supposition which is that of the retreat of the ocean, a theory which this author has adopted, it is as impossible to explain the present appearance of horizontal strata as of those that are inclined. At the same time, if a power placed below the strata is to be employed for the purpose of raising them from the bottom of the sea, to the place in which we find them at present, it is impossible that this should be done without the fracture of those strata in certain places; and it is much more difficult to conceive this operation not to be attended with changing the natural horizontal position of strata, and thus leaving them in many places inclined, than otherwise by supposing that this internal power of the globe should elevate the strata without changing their original position.

With this description of strata on the Rhine, we may compare that of M. Monnet respecting those which he found upon the Meuse, (Nouveau Voyage Min�ralogique, etc. Journal Physique, Aoust, 1784.)

Speaking of the schistus, or slate, he adds: �Mais ces petites veines nous donnent lieu de faire une observation importante; c'est qu'elles se pr�sentent assez communement perpendiculaire, tandis que les grands bancs d'ardoises, ceux qu'on exploite, sont, comme nous l'avons dit, couch�s sur une ligne de 15 � 20 degr�s. J'ai parl� des montagnes de marbre qui sont derri�re Givet, et de celles sur la quelle est situ� Charlemont. J'ai fait voir que bien loin que les bancs de marbre, qui forment la montagne du Givet, soient horizontaux comme on seroit tent� de le croire, d'apr�s les principes de quelques naturalistes syst�matiques, qui pensent que tous les bancs de pierres calcaires ne sauroient �tre autrement; j'ai fait voir, dis-je, que ces bancs sont presque perpendiculaire � l'horizon; et de plus, qu'ils sont tellement coll�s les uns contre les autres, qu'� peine on peut les distinguer.�

The changed structure and position of the strata, now exemplified from the observations both of M. de Saussure and M. de Luc, observations made in a great extent from France to Germany, show the effects without the means by which those effects had been produced; and, in this case, it is by judging from certain principles of natural philosophy that the cause is discovered in the effect.

We are now to see the deplacement of at least a great body of earth in another light, by having at the same time in our view both the cause and the effect. Nothing can give a more proper example of this than the mine of Rammelsberg; and no description better adapted to give a clear idea than that of M. de Luc, which I shall now transcribe. Lettres Phisiques et Morales, Tome 3. p. 361 to 364.

�Deux filons principaux occupent les mineurs dans le Rammelsberg: filons immenses, car ils ont jusqu'� 18 ou 20 toises d'�paisseur dans une �tendue dont on ne connoit pas encore les bornes. L'un de ces filons fait avec l'horizon un angle de 25 degr�s; c'est l'inf�rieur: l'autre s'�l�ve de 45 degr�s: et leur distance �tant peu consid�rable, leurs plans doivent se rencontrer dans un point qui n'est pas fort �loign� des mines. Leurs directions sont aussi diff�rentes: celle du filon de 35 degr�s est � 6� heures; et celle du filon de 45 degr�s est a 5h.-1/2: tellement qu'ils se croisent � l'endroit ou est perc� le puits des pompes.

�On est embarrass� d'expliquer l'�tat de cette montagne par des secousses. Il faut au moins supposer que la montagne enti�re a �t� culbut�e, et encore reste-t-il � comprendre, comment s'est soutenue cette grande piece qui s�pare les filons, et qui, en supposant vuides les espaces de ceux-ci, se trouveroit absolument en l'air.

�Ce ph�nom�ne important � l'histoire des montagnes, je veux dire ces intersections des filons, est tr�s fr�quent dans les mines et tr�s remarqu� par les mineurs. Il arrive souvent que des filons, qui sont � la m�me heure, c'est-�-dire, qui ont des directions semblables vers l'horizon, ont une chute ou inclinaison diff�rente, et telle que leurs deux plans se coupent � une certaine profondeur. Si le mineur ne s'en apper�oit pas assez t�t, et que des le commencement de son exploitation, il n'�tan�onne pas fortement partout ou il enlev� les filons, tout son ouvrage peut �tre �cras� par l'enfoncement de la pi�ce qui les s�paroit. Cette pi�ce m�me a un nom chez le mineurs; ils la nomment Bergkiel, c'est-�-dire coin de la mati�re de la montagne: et quand deux filons sont voisins l'une de l'autre, le g�om�tre souterrain en �tudie l'inclinaison pour juger � l'avance s'il y aura un Bergkiel; et qu'en ce cas la mineur prenne ses pr�cautions, en conservant des appuis naturels dans la gangue, ou s'en faisant d'artificiels, � mesure qu'il s'enfonce. Or si, en �levant les filons, ce coin se trouve sans appui; comment s'est-il soutenu avant que les filons fussent form�s?

�Voil� une question forte embarrassante. Mais peut-�tre n'a-t-on pas fait assez d'attention jusqu'ici � la mauvaise gangue, qui se trouve �tre de la m�me nature que la montagne. Peut-�tre trouveroit on par la, qu'en m�me tems que les fentes se font faites, il y est tomb� des pi�ces des c�t�s, qui ont emp�ch� la r�union des parties de la montagne; fragmens qui, aujourd'hui, font partie des filons, et qu'on pourroit laisser encore pour appuis naturels, n'exploitant qu'autour d'eux lorsqu'on auroit appris � les conno�tre.

�Ce peu d'inclinaison des filons du Rammelsberg rappelleroit l'id�e des couches form�es de d�p�ts successifs, s'ils �toient parall�les. Mais leur manque de parall�lisme en tout sens exclut cette explication. Car dans toutes les montagnes qui doivent leur formation aux d�p�ts des eaux, les couches sont parall�les; et l'on sent bien qu'elles doivent l'�tre.

�La nature des filons du Rammelsberg est aussi diff�rente de celle de Claustbat que l'est leur situation. C'est un massif compacte, et presque partout le m�me, de min�ral de plomb et argent pauvre, p�n�tr� de pyrite sulphureuse. Ils sont travers�s en plusieurs endroits par de Ruscheln, qui ont fait glisser le toit vers le mur; tellement que malgr� l'�paisseur de ces filons, on crut une fois en avoir trouv� la fin. Ils sont aussi coup�s dans leur int�rieur, en sens diff�rens, par d'autres plus petits filons, compos�s de mati�res tr�s diff�rentes; surtout d'une pyrite cuivreuse dure et pauvre, et que par cette raison on ne tente pas de s�parer.

�En mettant � part ces petits filons particuliers, ainsi que les Ruscheln, dus probablement les uns et les autres � des causes post�rieures � celles qui ont produit les filons principaux, la masse compacte de ceux-ci r�veille beaucoup l'id�e d'une mati�re fondue; en m�me tems qu'on seroit fort embarrass� � concevoir, d'o� viendroit cette mati�re, si distincte de toute autre, lorsqu'on voudroit l'attribuer � l'eau.

�Cette id�e, que je dois � Mr. de Redden, perfectionn�e par l'�tude des ph�nom�nes, donnera peut-�tre un jour le mot de toutes ces �nigmes.�

Here is the clearest evidence that an enormous mass of mountain had been raised by a subterranean force; that this force had acted upon an enormous column of melted minerals, the specific gravity of which is great; and that this fluid mass had suspended a great wedge of this mountain, or raised it up. Now, if by means which are natural to the globe, means which are general to the earth, as appearing in every mineral vein, this mass of mountain had been raised up and suspended twenty fathoms, there is no reason why we should suppose nature limited, whether in raising a greater mass of earth, or of raising it a greater height. That the height to which the land of this globe shall be raised, is a thing limited in the system of this earth, in having a certain bounds which it shall not exceed, cannot be disputed, while wisdom in that system is acknowledged; but it is equally evident, that we cannot set any other bounds to the operation of this cause, than those which nature appears actually to have observed in elevating a continent of land above the level of the sea for the necessary purpose of this world, in which there is to be produced a variety of climates, as there is of plants, from the burning coast under the equator to the frozen mountains of the Andes.

Here therefore we have, although upon a smaller scale, the most perfect view of that cause which has every where been exerted in the greater operations of this earth, and has transformed the bottom of the sea to the summits of our mountains. Now, this moving power appears to have been the effect of an internal fire, a power which has been universally employed for the consolidation of strata, by introducing various degrees of fusion among the matter of those masses, and a power which is peculiarly adapted to that essential purpose in the system of this earth, when dry land is formed by the elevation of what before had existed as the bottom of the sea.

I hope it will not be thought that too much is here adduced in confirmation of this part of the theory. The elevation of strata from their original position, which was horizontal, is a material part; it is a fact which is to be verified, not by some few observations, or appearances here and there discovered in seeking what is singular or rare, but by a concurrence of many observations, by what is general upon the surface of the globe. It is therefore highly interesting not only to bring together that multitude of those proofs which are to be found in every country, but also to give examples of that variety of ways in which the fact is to be proved. Were it necessary, much more might be given, having many examples in this country of Scotland, in Derbyshire, and in Wales, from my proper observation; but, in giving examples for the confirmation of this theory, I thought it better to seek for such as could not be suspected of partiality in the observation.

We have now discussed the proof of those mineral operations by which the horizontal strata, consolidated at the bottom of the sea, had been changed in their position, and raised into the place of land. The next object of our research is to see those operations, belonging to the surface of the earth, by which the consolidated and erected strata have been again dissolved, in order to serve the purpose of this world, and to descend again into the bottom of the sea from whence they came.

Of all the natural objects of this world, the surface of the earth is that with which we are best acquainted, and most interested. It is here that man has the disposal of nature so much at his will; but here, man, in disposing of things at the pleasure of his will, must learn, by studying nature, what will most conduce to the success of his design, or to the happy economy of his life. No part of this great object is indifferent to man; even on the summits of mountains, too high for the sustaining of vegetable life, he sees a purpose of nature in the accumulated snow and in majestic streams of the descending ice. On every other spot of the surface of this earth, the system of animal and vegetable life is served, in the continual productions of nature, and in the repeated multiplication of living beings which propagate their species.

But, for this great purpose of the world, the solid structure of this earth must be sacrificed; for, the fertility of our soil depends upon the loose and incoherent state of its materials; and, that state of our fertile soil necessarily exposes it to the ravages of the rain upon the inclined surface of the earth. In studying this part of the economy of nature, we may perceive the most perfect wisdom in the actual constitution of things; for, while it is so ordered that the solid mass of earth should be resolved for the purpose of vegetation, the perishable soil is as much as possible preserved by the protection of those solid parts; and these consolidated masses are resolved in so slow a manner, that nothing but the most philosophic eye, by reasoning upon a chain of facts, is able to discover it. Thus it may be concluded, that the apparent permanency of this earth is not real or absolute; and that the fertility of its surface, like the healthy state of animal bodies, must have its period, and be succeeded by another.

The study of this subject must tend to enlarge the mind of man, in seeing what is past, and in foreseeing what must come to pass in time; and here is a subject in which we find an extensive field for investigation, and for pleasant satisfaction. The hideous mountains and precipitous rocks, which are so apt to inspire horror and discontentment in minds which look at sensible objects only for immediate pleasure, afford matter of the most instructive speculation to the philosopher, who studies the wisdom of nature through the medium of things. As, on the one hand, the summit of the mountain may be supposed the point of absolute sterility, so, on the other, the sandy desert, moved by nothing but the parching winds of continents distant from the sources of abundant rains, finishes the scale of natural fertility, which thus diminishes in the two opposite extremes of hot and dry, of cold and wet; thus is provided an indefinite variety of soils and climates for that diversity of living organised bodies with which the world is provided for the use of man. But, between those two extremes, of mountains covered with perpetual snow, and parched plains in which every living thing must perish, we find the most pleasant subject of contemplation, in studying the means employed in nature for producing the beautiful and benevolent system of hills and valleys, of fertile soils and well watered plains, of the most agreeable circumstances and proper situations for every thing that lives, and for the preservation of an indefinite variety of organised bodies which propagate their species.

Without this philosophic view of things, the prospect of the surface of this earth is far from giving always satisfaction or contentment to the mind of man, who is subject to be continually displeased with that which is presented to his view, and which, in his opinion, is not the best; in his partial views of things, it is either too high or too low, too cold or too warm, too moist or too dry, too stiff for the labour of his plough, or too loose for the growing of his corn. But, considering nature as the common parent of living growing propagating bodies, which require an indefinite variety of soils and climates, the philosopher finds the most benevolent purpose in the end proposed, or effect which is attained, and sees perfect wisdom in the effectual means which are employed. This is the view that I would wish men of science to take; and it is for this purpose that I am now to examine the phenomena of the surface of this earth.

If strata, formed at the bottom of the sea, had been consolidated by internal operations proper to the earth, and afterwards raised for the purpose of a habitable world; and if, for the purpose of vegetation, the solid land must be resolved into soil by the dissolution and separation of its parts, as is required in the theory, the strata, instead of being entire immediately below the soil, should be found in a mutilated state; the ends of hard and solid beds should present their fractures or abrupt sections immediately under the confused materials with which they are covered; and the softer strata should appear to suffer gradual resolution and decay, by which may be perceived their transition into soil, the most important part of all the operations of the globe which do not immediately concern our life.

These are facts which every person of observation has it in his power to verify; they are facts for which nothing further can be laid than that the thing is truly so; and they are facts from which the most important arguments might be formed, were any doubt to be entertained concerning the justness of the theory which has now been given.

The theory consists in this, that it is necessary to have a habitable country situated in the atmosphere, or above the surface of the sea.

It is difficult to say precisely what constitutes a habitable country. A resting place out of the water suffices for such amphibious animals as, while they necessarily live in the atmosphere, feed in the sea. Man, more versatile in his nature than most animals, and more capable of adapting his manners to his circumstances, is even sometimes found subsisting in situations where the land affords him little more than it does the seal on which he feeds. The growth of terrestrial plants, however, seems necessary to the idea of a habitable country; and, for the growth of plants, there is required soil: Now, this is only to be procured by the resolution or decay of solid land.

We are not to consider the resolution of our land as being the effect of accident, while it is performed by the operations of the sun and atmosphere, by the alternate action of moisture and of drought, and by the casual operations of a river in a flood. Nothing is more steady than the resolution of our land; nothing rests upon more certain principles; and there is nothing which in science may be more easily investigated.

Calcareous, argillaceous, and other soluble earths, compose many of the strata; but in many more, which are partly or chiefly composed of insoluble substances, those soluble earths are mixed in various proportions. Now, when the siliceous substance, which is the insoluble part, shall be supposed resisting every effort of the elements towards its dissolution, those compound masses upon the surface of the earth, however endued with hardness and solidity, are gradually impaired by the dissolution of some of their constituent parts, and by the separation of others which are thus exposed to the ablution of water. In like manner, by the resolution of the surrounding parts, the solid silex, which is supposed to be insoluble, is removed from its bed, and thus suffers new parts of the solid land to be exposed to those injuries of the air, by which the general good of plants, of animals, and even of future worlds, are consulted.

The solid land is resolved into stones, gravel, sand, earths, and clays; all or either of these, by retaining moisture, and affording places for the roots of plants, are disposed for vegetation in different degrees; a mixture of the different earths being, upon the whole, the best suited to that purpose; and this compound body, mixed with vegetable or animal substances, becoming a most luxuriant soil.

Soils are thus formed, either by the resolution of the surface of that land upon which they are to rest, or by the transportation of those solid parts to be again deposited upon another basis. In this manner soils are constantly changing upon the same spot; sometimes they are meliorated, at other times impoverished. From the tops of the mountains to the shores of the sea, all the soils are subject to be moved from their places, by the natural operations of the surface, and to be deposited in a lower situation; thus gradually proceeding from the mountain to the river, and from the river, step by step, into the sea. Countries are thus formed at the mouths of rivers in the sea, so long as the quantities of materials transported from the land exceeds that which is carried from the shore, by tides and currents, into the deeper water.

The soil, with which the surface of this earth is always covered more or less, is extremely various, both with respect to quantity and quality; it is found resting upon the solid parts; and those solid parts are always more or less affected by the influences of the atmosphere near the surface of the earth. Those parts of the strata which approach the surface are always in a decayed state; and this sometimes may be observed for very considerable depths, according as the quality of the materials, and the situation of the place dispose to that effect. This general observation however may be formed, that, cet. par. the strata become always more solid, or are found in their sound and natural state, more and more in proportion as we sink into the earth, or have proceeded from the surface.

There is nothing of which we have more distinct experience than this, That, universally upon the surface of the earth, the solid parts are dissolving and always going into decay; whereas, at a sufficient depth below, they are found in their natural consolidated state. The operations of man in digging into the ground, as well as the sections of the earth so often formed by brooks and rivers, affords such ample testimony of this truth that nothing farther need be observed upon this head only that this is a most important operation in the natural economy of the globe, and forms a subject of the greatest consequence in the present Theory of the Earth, which holds for principle, that the strata are consolidated in the mineral regions far beyond reach of human observation.

Consistently with this view of things, the strata or regular solid parts, under the soil or travelled earth, should be found in some shape corresponding to the represented state of those things, when affected by the powers which have acted upon the surface of the earth. Here, accordingly, the strata are always to be observed with those marks of resolution, of fracture, and of separation, which have most evidently arisen from the joint operation of those several causes that have been now explained. But though every operation of the globe be necessarily required for the explanation of those appearances which we now examine, it is principally the action of the sun and atmosphere, and the operations of the waters flooding the surface of the earth, that form the proper subject of the present investigation.

It must not be imagined that, from the present state of things, we may be always able to explain every particular appearance of this kind which occurs; for example, why upon an eminence, or the summit of a ridge of land which declines on every side, an enormous mass of travelled soil appears; or why in other places, where the immediate cause is equally unseen, the solid strata should be exposed almost naked to our view. We know the agents which nature has employed for those purposes; we know the operations in which the solid parts are rendered soil of various qualities and for different purposes; and when we find the marks of those natural operations in places where, according to the present circumstances, the proper agents could not have acted or existed, we are hereby constrained to believe, that the circumstances of those places have been changed, while the operations of nature are the same.

It is thus that we shall find reason to conclude an immense period of time, in those operations which are measured by the depradations of water acting upon the surface of the earth; a period however which is to be esteemed a little thing compared with that in which a continent had taken birth and gone into decay; but a period which interests us the more to examine, in that it approaches nearer to another period, for the estimation of which some data may perhaps be found by naturalists and antiquaries, when their researches shall be turned to this subject. It is only in this manner that there is any reasonable prospect of forming some sort of calculation concerning that elapsed time in which the present earth was formed, a thing which from our present data we have considered as indefinite.

In this view which we are now taking of the surface of the earth, nothing is more interesting than the beds of rivers; these take winding courses around the hills which they cannot surmount; sometimes again they break through the barrier of rocks opposed to their current; thus making gaps in places by wearing away the solid rock over which they formerly had run upon a higher level; and thus leaving traces of their currents in the furrowed sides of rocky mountains, far from the course of any water at the present time.

So strongly has M. de Saussure been impressed with this and some other appearances, that he has imagined a current of water which, however in the possibility of things, is not in nature; and which moreover could not have produced the appearances now mentioned, which is the work of time, and the continued operation of a lesser cause. We are further obliged to him for the following facts.

Vol. 1. (page 163.) �Les tranches nues et escarp�es des grandes couches du petit et surtout du grande Saleve, pr�sentent presque partout les traces les plus marqu�es du passage des eaux, qui les ont rong�es et excav�es, on voit sur ces rochers, des sillons � peu pr�s horizontaux, plus ou moins larges et profonds; il a de 4 � 5 pieds de largeur, et d'une longueur double ou triple, sur 1 ou 2 pieds de profondeur. Tous ces sillons ont leur bords termin�s des courbures arrondies; telles que les eaux ont coutume de les tracer. Je dis qu'ils sont � peu pr�s horizontaux, parce qu'ils sont par fois inclin�s de quelques degr�s, en descendant vers le sud-sud-ouest, suivant la pente qu'a du avoir le courant.� This is evidently the effect of a river running along the side of a rock of such soft materials as may be worn by the friction of sand and stones; and such are the materials of the rocks now considered. Notwithstanding that it is so easy to explain this appearance by the operation of natural causes, M. de Saussure proceeds in taking it in another view. �De tels filons ne sauroient avoir �t� trac�s par les eaux des pluies; car celles-ci forment des excavations, ou perpendiculaires � l'horizon ou dirig�es suivant la plus grande inclinaison des faces des rochers; au lieu que celles la font trac�es presqu'horizontalement sur de faces tou-�-fait verticales.� Here our author takes it for granted that things upon the surface of this earth were always the same as at present; and he reasons justly from these principles. But we are now tracing a former state of things; and those furrowed rocks testify the former current of a river by their side.

This operation of rivers undermining the sides of mountains, and causing scenes of ruin and destruction, may be illustrated by what our author has described under the title of Ravage du temps sur les Rochers de Saleve, �236. �L� ou ces couches manquent, il est ais� de voir qu'elles ont �t� d�truites par le tems; les couches m�me horizontales, contres lesquelles elles out appuy�es, ont souffert en bien des endroits des alt�rations consid�rables.

�Un peintre qui voudroit monter son imagination, et se faire des grandes id�es des ravages du tems sur de grands objects, devroit aller au pied de Saleve, � l'extr�mit� des ces grands rochers, au-dessus du coin, hameau fort �lev� de la paroisse de Collonge.

�On voit l� des rochers taill�s � pic � la hauteur de plusieurs centaines de pied avec des faces, ici planes et uniformes, l� partag�es et sillonnes par les eaux.

�La base de ces rochers est couverte de d�bris et de fragmens �normes, confus�ment entass�s; un de ces d�bris soutenu fortuitement par d'autres est demeur�, et paro�t de pr�s un ob�lisque quadrangulaire d'une hauteur prodigieuse; de plus loin on reconno�t que sa sommit� est une arr�te tranchante, et qu'il a la forme d'un coin; et c'est peut-�tre cette forme qui a donn� son nom au hameau qu'il domine.

�L'Angle m�me de la montagne est partag� par une fente qui le traverse de part en part. Cette profonde fissure m�rite qu'on la voye, et m�me qu'on la p�n�tre. Elle est tortueuse, et dans quelques endroits si �troite, qu'� peine un homme peut il y passer. Quand vous y �tes engag�s vous trouvez des places ou les sinuosit�s du rocher vous cache le ciel, plus loin elles le laissent apercevoir par �chapp�es; ailleurs vous voyez des blocs de rochers engag�s dans la crevasse, et suspendus au-dessus de votre t�te.�

In his route from Contamine to Bonneville, he observes, page 365, �Enfin vis-a-vis la Bonne-ville, ces m�mes escarpemens des bases du mole, pr�sentent une grande �chancrure, qui paro�t �tre le vuide qu'a laiss� une montagne qui s'est anciennement �croul�e; ses d�bris sont encore entass�s au-dessous de l'�chancrure. Il paro�t m�me qu'elle �toit plus �lev�e que ses voisines, j'en juge par leur couches qui montent � droite et � gauche, contre le vuide qu'elle � laiss�.

�� 493. En suivant la route de servez, on voit sur sa gauche la continuation des rocs escarp�s qui couronnent les montagnes situ�es au-dessus de Passy. Un de ces rochers est si �lev�, et en m�me tems si mince que l'on a peine � concevoir qu'il puisse se tenir debout et r�sister aux orages.

�C'est aupr�s de cette sommit� �lev�e qu'�toit situ�e une montagne qui s'�boula en 1751, avec un fracas si �pouvantable, et une poussi�re si �paisse et si obscure, que bien de gens crurent que c'�toit la fin du monde.�

Vitaliano Donati, who was sent from Turin to examine this phenomenon, says in his letter, which M. de Saussure transcribes, that the great snows, which fell that year in Savoy, increasing the operation of some lakes, the waters of which continually undermined this mountain, occasioned the fall of three millions of cubic toises of rock.

In describing the Saleve, our author proceeds to mention other appearances equally conclusive with regard to the operations of water, but such as may be found over all the surface of the globe, to have been brought about by natural causes. �Ce que l'on nomme le Grottes de l'Hermitage, ou ces excavations profondes de 30 pieds, et 8 ou 10 fois aussi longues produites par la destruction totale de plusieurs couches de rocher.

�La gorge m�me de Monetier, ou cette grande �chancrure qui s�pare le grand Saleve du petit, et dans le fond de laquelle est renferm� le joli vallon de Monetier, paro�t avoir �t� form�e par un courant semblable, qui descendant des Alpes par la vall�e de l'Arve, venoit se jetter dans notre grand courant; car les couches correspondantes du grand et du petit Saleve indiquent leur ancienne jonction; et l'on ne comprend pas quel agent auroit pu d�tacher et emporter la pi�ce �norme qui manque en cet endroit � la montagne.�

Further, in treating of the changes made in the form of the Jura by the ravages of time, our author observes, page 273, vol. I.

�Le faite de la montagne, battu de tous cot�s par les vents, et par les pluies, a souffert des alt�rations les plus grandes: ici les couches du cot� du lac ont �t� detruites, et laissent voir les sommit�s des couches oppos�es, dont les escarpemens paroissent tourner contre ce m�me lac; l�, ce font les couches du cot� de la vall�e de Mijoux, qui out �t� emport�es, et la montagne en pente uniforme de notre cot�, est escarp�e du cot� de celle vall�e; plus loin, le faite entier a �t� enlev�, et l� on voit des abaissemens ou des gorges comme aux Faucilles, � St. Serge, etc.

�Les flancs et la base de La montagne ont aussi �t� d�grad�s par les torrens que produisent la pluie et les neiges fondues, qui ont form� de larges et profondes excavations.�

These ravages of time, or rather of the wasting operations of the surface of the earth, however great, compared with the little changes that we find in our experience, or in the most ancient record of our histories, are little things, considering the softness and solubility of the materials, and compared with the wasting of the Alps, which we find in tracing up those same rivers to their sources in the icy valleys. Let us go up the Arve to the valley of Chamouni. From this fertile valley, M. de Saussure heads us up the Montanvert, 428 fathoms above the level of the valley, and consequently 954 above that of the sea.

From this mountain we descend again into the high frozen valley which runs between the granite mountains, and pours its ice into the valley of Chamouni.

In this high valley, which communicates with an immensity of the like kind, we find ourselves among the most hard and durable materials. Here we must perceive, that most enormous masses of those solid materials had, in the course of time, been wasted by the flow effects of air and water, of the sun and frost, in order to hollow out those barren valleys of immense extent, which have, during an amazing tract of time, contributed from their solid rocks to the formation of travelled soils below, but which materials have long ago been travelling in the sea. The sides of those valleys are solid rock here exposed naked to our view. It is to such a place as this that we should go to see the operations of the surface wasting the solid body of the globe, and to read the unmeasurable course of time that must have flowed during those amazing operations which the vulgar do not see, and which the learned seem to see without wonder!

M. de Saussure, in his second volume of Voyages dans les Alps, has given us a most interesting view of this scene, p. 6.

�En montant au Montanvert, on a toujours sous ses pieds la vue de la vall�e de Chamouni, de l'Arve qui l'arrose dans toute la longueur, d'une soule de villages et de hameaux entour�s d'arbres et de champs bien cultiv�s. Au moment ou l'on arrive au Montanvert, la sc�ne change; et au lieu de cette riante et fertile vall�e, on se trouve presqu'au bord d'un pr�cipice, dont le fond est une vall�e beaucoup plus large et plus �tendue, remplie de neige et de glace, et bord�e de montagnes colossales, qui �tonnent par leur hauteur et par leurs formes, et qui effraient par leur st�rilit� et leurs escarpements.�

It is the cause of this appearance, of deep valleys and colossal mountains, that I would now wish my readers to perceive. This is a thought which seldom strikes the mind of wondering spectators, viewing those lofty objects; they are occupied with what they see, and do not think how little what they see may have been, compared with what had been removed in the gradual operations of the globe. We have but to suppose this scene hewn out of the solid mass of country raised above the level of the valley; and, that this had been the case, must appear from the examination of all around.

Let us follow our author up those valleys between the solid granite mountains, valleys which properly are great rivers of ice moving, grandly but slowly, the ruins of those mountains upon which they were gathered. It is the Glacier de Bois upon which he is set out, (p. 26.)

�Apr�s une bonne demi-heure de marche sur le glacier, nous traversons une arr�te de glace charg�e de terre, de sable et de d�bris de rocher. J'ai parl� dans le 1er. vol. de ces arr�tes parall�les � la longueur de glaciers, que l'on voit souvent dans le milieu de leur largeur, ou � des distances plus ou moins grandes de leurs bords. J'ai fait voir qu'elles sont produites par des d�bris qui du haut des montagnes, roulent sur le glacier, et qui entra�n�s par la glace sur laquelle ils reposent suivent comme elle une direction oblique en descendant tout-�-la-fois vers le milieu et vers le bas de la vall�e.

�Dix minutes apr�s, nous travers�mes une seconde arr�te plus haute que la premiere, et nous juge�mes que sous ces d�bris la glace �toit de 20 ou 25 pieds plus �lev�e que dans les endroits o� l'air et les rayons du soleil agissent librement sur elle. On rencontre une troisi�me arr�te � vingt minutes de la seconde, et la quatri�me, qui est la derni�re, la suit de tr�s-pr�s.

�Ici nous nous trouvons au point o� le glacier des bois se divise, comme je l'ai dit, � 611, en deux grandes branches, dont l'une tourne � droite vers le Mont-Blanc, et prend le nom de glacier de Tacul, et l'autre � gauche se nomme le glacier de Lechaud. Il seroit, sans doute, plus int�ressant de suivre celle de la droite, et de s'approcher ainsi du Mont-Blanc; ses pentes de neige et de glace, qui se presentent � nous, semblent m�me n'�tre point absolument inaccessibles: mais ce sont des apparences trompeuses; des glaciers entrecoup�s de profondes crevasses masqu�es �� et l� par des couches minces de neige les approches de cette redoutable montagne, quoique peut-�tre en choisissant une ann�e ou il seroit tomb� beaucoup de neige, et en prenant le temps o� cette neige seroit encore ferme, quelque chasseur adroit et courageux pourroit tenter cette route.

�Comme dans ce moment cette entreprise est absolument impraticable, nous suivons la branche gauche de la vall�e, et apr�s deux heures de marche sur le glacier des bois, nous en sortons au pied de celui du Tal�fre, c'est-�-dire, � l'endroit o� celui-ci vient verser sa glace dans celui-l� qui a chang� de nom, et qui s'appelle ici le glacier de L�chaud.

�La vue du glacier du Tal�fre est ici majestueuse et terrible. Comme la pente par laquelle il descend est extr�mement rapide, les gla�ons se pressant mutuellement, se dressent, se rel�vent, et pr�sentent des tours, des pyramides diversement inclin�es, qui semblent pr�tes � �craser le voyageur t�m�raire qui oseroit s'en approcher.

�Pour parvenir au sommet de ce glacier, o� il est moins inclin� et par cela m�me moins in�gal, nous gravissons le rocher qui est � la gauche du c�t� du couchant. Ce rocher se nomme le Couvercle; il est domin� par une cime inaccessible, qui, suivant l'usage du pays, est d�cor�e du nom aiguille, et, en prenant le nom du glacier le plus proche, s'appelle l'aiguille du Tal�fre.

�La pente, par laquelle on gravit le couvercle, est excessivement rapide; on suit une esp�ce de sillon creus� dans le roc par la nature; quelques pointes de roc aux quelles on se cramponne, en montant avec les mains, autant et plus qu'avec les pieds, ont fait donner � ce passage le nom d'�gralets ou de petits degr�s. Ce passage n'est cependant point dangereux, parce que le roc, qui est un granit tr�s-coh�rent, permet d'assurer toujours solidement les mains et les pieds; mais la rapidit� le rend un peu effrayant � la descente.

�Lorsqu'on est au haut des �gralets, on suite un pente beaucoup moins rapide; on marche tant�t sur du gazon, tant�t sur de grandes tables de granit, et on arrive ainsi au bord du plan du glacier du Tal�fre. On nomme le plan d'un glacier la partie �lev�e et �-peu-pr�s horizontale dans laquelle on peut le traverser.

�Nous avions mis une heure et un quart � monter du glacier de L�chaud au plan de celui du Tal�fre. Nous fumes tent�s de nous reposer un moment avant d'entrer sur celui-ci. Tout nous invitoit � choisir cette place, un beau gazon arros� par un ruisseau qui sortoit de dessous la neige et qui rouloit son eau crystalline sur un sable argent�, et ce qui �toit plus s�duisant encore, une vue d'une �tendue et d'une beaut� dont une description ne peut donner qu'une bien foible id�e.

�� 631. En effet comment peindre, � l'imagination des objets qui n'ont rien de commun avec tout ce que l'on voit dans le reste du monde; comment faire passer dans l'�me du lecteur cette impression m�l�e d'admiration et de terreur qu'inspirent ces immenses amas de glaces entour�s et surmont�s de ces rochers pyramidaux plus immenses encore; le contraste de la blancheur des neiges avec la couleur obscure des rochers, mouill�s par les eaux que ces neiges distillent, la puret� de l'air, �clat de la lumi�re du soleil, qui donne � tous ces objets une nettet� et une vivacit� extraordinaires; le profond et majestueux silence qui regne dans ces vastes solitudes, silence qui n'est troubl� que de loin en loin par le fracas de quelque grand rocher de granit ou de glace qui s'�croule du haut de quelque montagne; et la nudit� m�me de ces rochers �lev�s, o� l'on ne d�couvre ni animaux, ni arbustes, ni verdure. Et quand on se rappelle la belle v�g�tation, et les charmans paysages que l'on a vus le jours pr�c�dens dans le basses vall�es, on est tent� de croire qu'on a �t� subitement transport� dans un autre monde oubli� par la nature, ou sur une com�te dans son aph�lie. La vue du Montanvert ne donne de celle-ci qu'une id�e tr�s-imparfaite; l� on ne voit qu'un seul glacier, au lieu que d'ici vous voyez les trois grands glaciers des Bois, de L�chaud et du Tacul, sans compter un grand nombre d'autres moins consid�rables qui, comme celui du Tal�fre, versent leurs glaces dans les glaciers principaux.

�Les rochers innombrables que l'on voit au-dessus de ces glaciers sont tous de granit, car s'il y a, comme j'en suis certain, des rochers feuillet�es, interpos�es entre ces granits, des gneufs, par exemple, ou des roches de corne; comme elles �toient plus tendres que les granits, leurs parties faillantes ont �t� d�truites par les injures de l'air, et il ne reste plus que leurs bases, cach�s au fond des gorges qui s�parent les hautes pyramides.�

This is a fact which, independent of the good authority we have here, we would have been naturally led, from the theory, to suppose. For, in wearing out the solid mass, which had been once continuous among those mountains, something must have determined the situation of those valleys; but what so likely as some parts more destructible by the wasting operations of the surface than others, which are therefore less impaired, and remain more high.

Now, whatever may be our theory with regard to the origin or formation of these solid masses of the globe, this must be concluded for certain,--that what we see remaining is but a specimen of what had been removed,--and that we actually see the operations by which that great work had been performed: we only need to join in our imagination that portion of time which, upon the surest principles, we are forced to acknowledge in this view of present things.

To have an idea of this operation of running water changing the surface of the earth, one should travel in the Alps; it is there that are to be seen all the steps of this progression of things, and so closely connected in the scene which lies before one, that there is not required any chain of argument, or distant reasoning from effect to cause, in order to understand the natural operations of the globe, in the state of things which now appears. So strongly are the operations of nature marked in those scenes, that even a description is sufficient to give a lively idea of the process which had been transacted. With this view, I shall here transcribe, from the Tableau de la Suisse, a description of that remarkable passage by the mountain of St. Gothard, from Switzerland to Italy, hoping, that, even independent of the illustration hereby given to the theory, the reader will be pleased to see such a picture of that country as will either excite new ideas in a person who has not seen such scenes, or call up those which it is proper for a naturalist to have[4].

[Footnote 4: Tableaux de la Suisse Discours, etc. p. 113. Route d'Altorf au St. Gothard.]

�Nous allons donner les observations que nous avons faites, en montant le Saint Gothard par le c�t� septentrional, et nous terminerons ce que nous avons � dire par la description du haut de cette montagne. Il y a aux environs d'Altorf, chef-lieu du canton d'Uri, de grands terrains couverts de pierres roul�es, dont la plus grande partie est amen�e par le Schechen, torrent qui descend de la vall�e du m�me nom, et l'autre par la Reuss qui descend du St. Gothard. Sans se donner beaucoup de peines, on y a la facilite de voir et d'examiner une grande vari�t� de pierres d'esp�ces diff�rentes et de conno�tre d'avance les rochers qui composent les montagnes qu'on va parcourir; nous r�p�tons ici que toutes les pierres arrondies ont pris cette forme par le roulis qu'elles ont essuy�es dans les torrens, en se pr�cipitant avec les eaux qui les ont amen�es: plus nous avons parcouru de montagnes, plus nous nous sommes confirm�s que cette observation �toit vraie et exact. Si on a la constance de suivre une esp�ce jusqu'au lieu de son origine ou position premiere, on l'y trouvera anguleuse, et n'ayant subi d'autres changemens que celui que le tems imprime � toutes les substances qui restent en place; on verra qu'� mesure qu'elles s'�loignent de leur premiere position leurs angles et leurs parties saillantes se d�truisent, et qu'elles finissent par prendre la forme ronde ou approchante, en raison de leurs duret� et du chemin qu'elles auront parcouru. Nous renvoyons � ce sujet ce qui a �t� dit vers le commencement de ces observations, en parlant du Trient. Nous ajoutons seulement qu'il n'y a gu�re d'esp�ce de pierres roul�es dans les montagnes, dont nous n'ayons pas trouv� les rochers analogues, et qu'avec du tems et les courses convenables, en observant bien les directions des montagnes et des torrents, on les trouveroit toutes. Altorf est entour� de tr�s-hautes montagnes, des vallons aboutissent de tous c�tes dans ses environs, parce-que c'est le lieu le plus bas o� les eaux vont se jetter dans le lac de Wahlasthall ou de Lucerne, � l'extr�mit� duquel Altorf est situ�; le vallon est assez couvert dans le bas, il est cultiv� dans quelques parties, et il y a des arbres fruitiers; c'est sur-tout aux environs de Birglen qu'on rencontre beaucoup de pierres roul�es et des rochers amen�s par les eaux.

�Les rochers sont de pierre calcaire, et continuent jusqu'� Silenen � deux lieues d'Altorf; les montagnes sont fort hautes et fort escarp�es des deux c�t�s du vallon, de beaux pr�s sont dans le bas; quelque arbres fruitiers et sur-tout des noyers sont � mi-c�te, et entre les rochers, des for�ts de sapins. Avant d'arriver � Silenen, on apper�oit le glacier de Tittlis; il est sur le territoire d'Engelberg, et on trouve encore quelques h�tres; derri�re les montagnes bois�es il s'en �l�ve d'autre nues et arides. Des points et des vues admirables par la d�gradation des montagnes et pour le sauvage, s'offrent de toutes parts. Des chalets, des habitations isol�es, sont situ�s au pied des plus affreux rochers qui les menacent d'une ruine prochaine. L'habitant y vit sans crainte, entour� de son pr� et de son petit bien dont il est tranquille possesseur.

�La chaleur concentr�e dans ce vallon y fait m�rir diff�rentes productions peu recherch�es; � la verit�, ce sont des fruits fort communs, excellens pour le pays, parce qu'on n'y en connoit pas de meilleurs. C'est du petit village d'Amsteeg entour� de fort hautes montagnes, qu'on commence � monter ce qu'on nomme le Saint Gothard general: le chemin devient plus roide, la Reuss y est plus resserr�s et roule ses eaux dans un lit fort profond et tr�s-escarp�, des torrens des cascades, tombent de diff�rens endroits des deux c�t�s de ce vallon et de belles for�ts de sapin, o� il y a des arbres prodigieux pour la hauteur, varient les points de vues; on s'�l�ve beaucoup au-dessus du fond des vallons par des chemins rapides: l'exposition plus heureuse fait cultiver du jardinage et des arbres fruitiers; il y a beaucoup de chanvre dans ces environs. De l'autre c�t� du vallon, sur la gauche de la Reuss, est une usine ou on fabriquoit de l'alum et du vitriol, les travaux ont cess�, ces �tablissemens et l'exploitation des mines sont peu connus et peu suivis en Suisse. La Reuss semble toujours s'enfoncer d'avantage, par-tout elle roule ses flots avec bruit et fracas, elle s'est creus�e un lit � des profondeurs incroyables; il n'y a point d'endroit ou l'on puisse mieux voir cet �tonnant travail des eaux que sur le pont du Pfaffensprung, � une demi-lieue de Vassen; il est � une hauteur si effrayante que le premier mouvement, quand on regarde au bas du pont, est de se tenir au parapet, et le second de le quitter, dans la crainte qu'il ne manque, ce n'est que par r�flexion qu'on y revient, On voit la progression et le travail successif de l'eau du haut jusqu'en bas; la roche a des sinuosit�s o� des angles arrondis, rentrans et faillans, alternativement de chaque c�t�, et dont saillans sont opposes aux rentrans, de fa�on qu'il reste peu d'espace pour apercevoir l'eau, ce canal ou ce, gouffre n'ayant pas plus de deux toises et demie de large. Depuis Silenen on ne voit plus de pierres calcaires, les rochers sont schisteux argileux, m�l� de beaucoup de quartz; le lit de la Reuss est rempli de granits, mais qui viennent des montagnes sup�rieures. Au-dessus du pont, dont nous venons de faire mention, on rencontre un passage des plus pittoresques, compos� de moulins, de scieries, de chutes d'eau, domin�s par le village de Vassen, et entour�s de montagnes fort extraordinaire. Une roche argileuse sur un plan inclin�, s'est d�tach�e de la hauteur, et a emport� un pont et un moulin.

�On monte beaucoup apr�s avoir pass� Vassen; ces environs sont d'une vari�t� �tonnante pour la beaut� et la singularit� des paysages. Des nappes d'eau, des cascades qui se pr�cipitent de roches en roches, forment dix et quinze chutes avant de se perdre dans les sapins qui contrastent avec la blancheur des eaux toutes r�duites en �cume. Des maisons d'une construction particuli�re, plac�es contre les rochers pour les mettre � l'abri des avalanches, des poutres jet�es sur diff�rentes masses de rochers pour passer la Reuss et autres torrens dont les eaux sont bouillonnantes et jaillissantes, des arcades de pierres pour joindre des rochers suspendus sur ces pr�cipices, rochers de mille formes bizarres occupent le voyageur, et ne lui donnent plus le tems d'apercevoir les mauvais pas qu'il franchit. Il y a sans doute des hommes assez malheureux, qui ne verroient que des dangers, et ne seroient occup�s que de leurs craintes et des terreurs paniques; c'est en effet une grande privation de ne pas sentir les beaut�s de la nature, elle devient un malheur r�el quand ce plaisir se trouve remplac� par des angoisses et de la frayeur. Un tableau d'un autre genre nouveau, et pour lequel les expressions manquent, est une for�t ras�e et abattue par une avalanche, il y a quelques ann�es, ces sapins de plus de cent pied de long, ont eu le tems de perdre leurs feuilles et de permettre � la vue de passer � travers cette �norme quantit� de bois et de branches entre lac�es de mille mani�res bizarres, et d'apercevoir des rocs �pars, des eaux qui circulent autour, et tombent quelque fois en cascades. C'est une spectacle qui devient effrayant quand on pense � la force et � la violence du moyen qui a pu occasionner un pareil effet. On recueille dans ce canton la r�sine des m�l�zes. Quoique Vassen soit d�j� fort �lev�, on y cultive encore quelque jardinage, et il y a aussi quelque cerisiers sauvages. Il y a environ cinq-lieues jusqu'� Altorf.

�Apr�s avoir pass� Vassen, on trouve cinq ou six superbes cascades form�es par la Reuss. Elle fait un bruit � �tourdir: la chaleur qu'il faisoit, avoit procur� une abondante fonte de neige, et l'eau avoit beaucoup augment� depuis le matin. Des bouleaux, des sapins, et des m�l�zes, group�s ensemble, formoient des contrastes agr�ables par la vari�t� et le m�lange des diff�rens verts. Les chemins sont faits � grand frais et avec beaucoup de soin; on a jett� des arcades en diff�rens endroits pour joindre les rochers, et faire passer les chemins par-dessus; on entend mugir la Reuss sous ses pieds elle �cume par-tout, il faut �tre accoutum� � ce spectacle pour n'en pas �tre effray�. Les rochers de droite et de gauche sont par-tout � pic et d'une granit, qui est jaun�tre dans diff�rens endroits; dans d'autres, il est d�compos�, passant � l'�tat d'argile; c'est le felds-path qui subit le premiere ce changement. Des quartiers de rochers des parties de montagnes sont �pars; des chalets, des habitations solitaires sont plac� aux environs des endroits o� il y a quelque p�turage. Il y a un de ces rochers qui est une belle masse de granit, appell�e la Pierre du Diable; on n'oublie pas de la faire remarquer, parce qu'il y a un conte populaire � son sujet que de graves auteurs nous ont conserv�. Le vallon se r�tr�cit beaucoup avant d'arriver � Gestinen.

�On a �lev� par-tout de murailles � de tr�s-grandes hauteur pour faire le chemin. Tout ce travail, vu le local, est incroyable pour la difficult�; de gros blocs de granits sont rang�s sur les bords du chemin pour servir de barri�res dans les endroits les plus dangereux. Ces passages sont si �troit qu'il faut peu de chose pour les interrompre. Le pont du Diable est d'une seul arche � plein ceintre de quatre toises d'ouverture deux et demie de large, et de douze toises d'�l�vation au-dessus de l'eau; le fracas et la rapidit� avec laquelle l'eau passe sous ce pont, ne permettent gueres qu'on la consid�re tranquillement de dessus le pont, on est toujours tent� de s'en �loigner.--La distance depuis Gestinen jusqu'� Teufelsbruck ou pont du Diable, qui est environ deux lieues, suffit pour prouver ce que nous disons; cette vall�e, qu'on nomme Schollenen, offre � chaque pas des difficult�s vaincues, des rochers franchis, des intervalles combl�s par des murailles, o� il a fallu employer des montagnes de pierres.

�Les chemins sont pav�s partout mieux que dans beaucoup de villes; des chevaux et des mulets charg�s les fr�quentent toute l'ann�e; et dans quels pays ces grands travaux ont-ils �t� ex�cutes? Dans un v�ritable chaos de rochers et montagnes dont partie sont boulevers�s, et l'autre paro�t pr�te � s'�crouler sur le passant, qui ne voit sous ses pieds que des �cueils, des gouffres et des pr�cipices, au fond desquels roule un torrent �cumant et furieux. Si les rochers sont mena�ans, les avalanches sont encore plus dangereuses dans ce redoutable passage; il n'y a point d'ann�e qu'il ne p�risse des hommes et des b�tes de somme; on fait voir un endroit o� une avalanche transporta � plus de cent toises au-dela de la Reuss, dix-neuf chevaux et mulets charg�s ainsi que leurs conducteurs; dans d'autres endroits des quartiers de rochers prodigieux qui ont �t� d�plac�s et transport�s de m�me.

�Apr�s avoir pass� le pont du Diable, le chemin tourne � gauche, puis � droite, pour monter une rampe assez rapide, tr�s-bien pav�e, qui conduit � une ouverture dans le rocher, c'est le seul passage qui se presente, nomm� Urner-Loch, trou du pays d'Urner ou Urseren; un rocher fort �lev� est sur la gauche, et les cascades de la Reuss � droite; l'entr�e du passage est obscure, c'est une galerie souterraine pratiqu�e dans le roc, haute de neuf pieds environ de fa�on qu'un homme peut y passer � cheval, de onze pieds de large et trente-deux toises de long; on a pratiqu� dans le milieu une ouverture pour donner du jour; cette roche est toute de granit, ainsi que celles qui sont autour du pont du Diable; Il y a environ soixante ans que cette galerie a �t� ouverte; le chemin passoit auparavant en dehors sur une esp�ce de pont qui tournoit le rocher, et se trouvoit exactement suspendu et fort mal assur� au-dessus des cascades de la Reuss; de frequens accidens, de grands frais pour reconstruire et entretenir ce pont, souvent entra�n� par les eaux, ont necessit� l'ouverture de ce passage.

�En sortant de ce passage obscur, on est surpris d'entrer dans une plaine ouverte, riante et couverte de verdure, et de voir couler � c�t� de soi une onde limpide et tranquille. Ce tableau est d'autant plus frappant qu'on vient de voir le contraste le plus effrayant; ce passage souterrain est comme le rideau qui se l�ve entre deux d�corations, dont l'une representoit le chaos et le bouleversement de la nature, et l'autre celle de la nature naissante et par�e des premiers et des plus simples ornemens; cette plaine est unie, de forme ovale, couverte d'un vaste gazon et de p�turages, entre lesquels serpente doucement la Reuss: sur ces bords il y a quelques buissons et peu d'arbres, ce sont des aulnes. Des cabanes de bois, des chalets isol�s et solitaires sont r�pandus ca et l� � l'entr�e du vallon: � gauche est le village d'In-der-Matt b�ti en pierres, et � neuf; dans le fond celui de hospital et situ� sur le penchant d'un coteau, il est domin� par une grosse tour: les montagnes du St. Gothard servent de fond au tableau, elles sont trop �loign�es pour laisser apercevoir leur aridit�; des montagnes nues, couvertes d'une verdure l�g�re sans arbres et sans buissons, bordent les deux c�t�s du vallon: enfin tout paro�t jeune et d'une cr�ation nouvelle au premier coup d'oeil, qui met le spectateur dans l'�tat o� est un homme � son r�veil apr�s un r�ve �pouvantable, o� il n'a vu que des objets effrayans; il se trouve heureux et content d'�tre en s�ret� et hors des dangers qui le mena�oient, tant les impressions de son r�ve lui sont encore pr�sentes.

�Ce vallon offre des remarques int�ressantes pour l'histoire naturelle, sa position, sa forme, et son nivellement ne laissent aucun doute que cet emplacement n'ait �t� le s�jour des eaux; en examinant les bords du lit de la Reuss, on reconno�t que le terrain de ce vallon est par couches horizontales de pierres argileuses; le pied des montagnes qui entourent le vallon sur la droite est de pierre calcaire grise, � la m�me hauteur, et � mi-c�te, sur la gauche, on trouve de la pierre ollaire. Voil� encore une de ces circonstances o� il seroit int�ressant de conno�tre la hauteur exacte de cette pierre calcaire, et de pouvoir comparer son niveau avec d'autres que nous avons d�j� observ� �tre aussi d�pos�es au pied des montagnes dans de petits vallons fort �lev�s, analogues � celui dont il est question. Quelque secousse aura rompu l'enceinte de rocher qui fermoit ce bassin: l'�coulement des eaux aura achev� de creuser ce passage, o� coule actuellement la Reuss, et le vallon qui est au-dessous. Quoique les angles rentrans et saillans des montagnes ayent lieu dans quelque endroits, il s'en faut de beaucoup que ce soit une r�gle certaine: le vallon qui descend du Saint Gothard � Altorff est une de ces exceptions. Une autre chose remarquable dans ce vallon, c'est qu'au sortir du passage souterrain que nous avons dit �tre creus� dans le granit, il y a tout � c�t� sans interruption, et formant la m�me masse de rocher, de la pierre schisteuse micac�e, m�l�e de quartz, dont les couches sont perpendiculaire, se fendent et tombent par morceaux, qui ont la forme de poutres ou de bois �quarris. Cette esp�ce de roche est aussi haute que celle de granit, et compos�e, dans des proportions diff�rentes, des m�mes parties int�grantes que le granit; n'a-t-elle pas �t� appos�e et form�e contre celle de granit, qui assur�ment doit �tre plus ancienne, puisqu'elle est envelopp�e par la roche schisteuse[5]?

[Footnote 5: Here is an example of the junction of the granite with the schistus; and probably here will be a proper opportunity of investigating the formation of those two things. Our author here supposes the granite to be the primary, and the schistus to be the secondary body; on the contrary, I believe that schistus to be the primary in relation to the granite, and that the granite had invaded the schistus, as will be made to appear in its proper place.]

Ce vallon, d'une bonne lieue de longueur sur moiti� de largeur, peut occasionner bien des r�flexions; nous avons �t� oblig� de passer rapidement sur ces objets, nous ne faisons que les indiquer. Au-haut de la montagne rapide, qui est au-dessus du village d'In-der-Matt, il y a un petit bois de sapins, auquel il est d�fendu de toucher sous peine de la vie. Il est r�serv� contre les avalanches; ce sont les seules arbres qu'on voie sur les hauteurs environnantes; derri�re ce bois on apper�oit un glacier d'o� descend un torrent qui va se jetter dans la Reuss; il am�ne, ainsi que les autres qui descendent de ce cot�, des pierres schisteuses micac�es, m�l�es de quartz, de m�me nature que celle qui est � cot� du passage souterrain. On monte par un beau chemin au village de Hospital, qui d�pend aussi du pays d'Urseren: tout ce canton est renomm� pour ces excellens fromages. Il n'y a que des p�turages et point d'autre culture. Le bois, qui est de premi�re n�cessit� dans un pays aussi froid, aussi �lev� et toujours entour� de neige, y manque totalement, on est oblig� de l'aller chercher dans la vall�e de Schollenen, et on traine sur la neige le bois de charpente. Le village de Hospital est situ� sur des roches schisteuses m�l�es de mica et de quartz, elles sont bleues, verd�tres, et grises. C'est � Hospital qu'est la rencontre de diff�rens chemins pour passer le Saint-Gothard; il y en a un qui venant du Vallais, passe � c�t� du glacier du Rh�ne et par la montagne de Fourk. Un second qui vient des Grisons, passe par Disentis et Chiamut entre les sources du bas Rhin. Ce sont des sentiers: qu'on juge de ce qu'ils peuvent �tre d'apr�s le grand chemin que nous venons de d�crire, qui conduit de la Suisse en Italie.

�Sur la droite du village de Hospital est un vallon que nous avons visit� jusqu'au village de Zum-d'Orff, � une grand demi-lieue. Il y r�gne aussi une couche de pierre calcaire � m�me hauteur, au bas de la montagne qui renferme le vallon, et nous prions de remarquer qu'elle est aussi sur la droite, et que sur la gauche il y � de pierre ollaire; une masse �norme de cette esp�ce, sous laquelle on travailloit depuis long-tems pour en tirer de quoi faire des po�les, ayant perdu son �quilibre, est tomb�e sur le c�t�. Les rochers qui dominent, sont des rochers schisteuse micac�es avec du quartz. Ce dernier village fait aussi partie de la vall�e d'Urseren, c'est le pays habit� le plus �lev� de l'Europe; les habitons sont forts et robustes; les montagnes de ce canton �tant nues, arides, et fort rapide, les avalanches y sont fr�quentes.

�C'est au sortir de Hospital qu'on monte v�ritablement le Mont Saint Gothard: le chemin est escarp�, pav�, et bien entretenu. Par un vallon � droite descend le Garceren, torrent qui vient des glaciers; son eau est blanch�tre, se jette dans la Reuss, et en trouble la limpidit�; les rochers sont de plus en plus d�pouill�s, secs et arides, on trouve les derniers buissons, des aulnes rabougris. La Reuss tombe de rocher en rocher, des blocs et des quartiers �normes, qui remplissent son lit, lui barrent souvent le passage; ses eaux s'�lancent par-dessus quand elle ne peut le contourner; on ne voit enfin que des rochers, des abymes et des pr�cipices; on marche n�anmoins en s�ret� au milieu de ce d�sordre de la nature; les chemins sont bien pav�s, et assez larges pour que deux chevaux ou deux mulets charg�s puissent y passer de front. Sur un rocher � droite, � une lieue de Hospital environ, on trouve taill�s dans le roc les limites entre le pays d'Urseren, et la partie Italienne ou vall�e de Livenen; ainsi tout sommet du St. Gothard appartient � la partie Italienne, qui est actuellement sujette du canton d'Uri. On parvient enfin sur un terrain plus uni, et une esp�ce de plateau, c'est le haut du Saint Gothard; � une demi-lieue sur la droite, entre des rochers forts hauts, forts escarp�s et � pic, est une esp�ce d'entonnoir, ou se rassemblent les eaux des neiges fondues; elles y forment le petit lac de Luzendro, gel� le trois quarts de l'ann�e, d'ou la Reuss tire sa source en partie; car le glaciers du mont de la Fourche ou Fourk dans le haut Vallais, fournissent aussi un torrent qui est regard� comme la seconde source de la Reuss; le Rh�ne prend sa source dans la partie oppos�e du m�me glacier. Le haut du Saint Gothard est un vrai vallon, puisque des cimes, des pyramides, des montagnes prodigieuses, compos�es toutes de rochers, s'�l�vent au-dessus, et l'entourent de tous c�t�s. L'espace qui est entre ces rochers a une forme a-peu-pr�s circulaire; il paro�t avoir �t� un fond qui a �t� �lev� et combl� jusqu'au point ou il est par les d�bris des montagnes qui le dominent, et qui s'y amonc�lent encore actuellement sous nos yeux; il a une esp�ce de niveau qui va un peu en pente du c�t� du midi, et du c�t� du Nord par lesquels se fait l'�coulement des eaux fournies par la fonte des neiges, dont la Reuss et le Tessin sont les canaux. Des masses �tonnantes de rochers remplissent la surface de ce vallon: elles y sont plac�es dans une d�sordre qui ne ressemble point aux positions des rochers actuels, et autorise � croire qu'elles y ont �t� jet�es et culbut�es au hazard. Ces masses isol�es sont toutes de granit, compos� de quartz, de feldspath, et de mica verd�tre; le chemin qui traverse ce vallon tourne autour de ces masses. Il faut que les pics �lev�s qui bordent ce vallon ayent �t� beaucoup plus hauts qu'ils ne le sont actuellement pour avoir pu fournir � combler cette �tendue, qui a une lieue au moins. Il n'est pas douteux non plus, que les vastes montagnes qui font au pied de toutes celles qui forment l'enceinte du Gothard, au moyen desquelles on trouve un acc�s plus facile, et des rampes moins rapides pour s'�l�vent comme par degr�s � cette hauteur, qui composent enfin ces montagnes de seconde et de troisieme formation, ne doivent leur existence qu'aux d�bris de ces colosses qui dominent tout. L'examen de ce qui se passe sous nos yeux journellement, ne peut nous laisser aucun doute sur l'abaissement de montagnes. Il n'y a point de torrent, point d'�coulement d'eaux, quelque petit qu'il soit, qui n'entra�ne en descendant des montagnes, des terres, des graviers, ou des sables, pour les porter plus bas. Les grands torrens, les fleuves, les rivi�res, gonfl�s par les fontes subites des glaces et des neiges, entra�nent des rochers enti�res, creusent de vastes et profonds ravins; ces masses de rochers diminuent par le choc et le frottement qu'elles essuient entre elles, et sur les rochers sur lesquels elles passent, dont elles occasionnent reciproquement la destruction; ce sont des d�bris de cette esp�ce de trituration qui troublent les eaux, et dont le d�p�t �l�ve insensiblement les bords des rivi�res, forme le limon f�condant de nos plaines, et va former jusque dans le sein des mers ces atterrissemens, ces barres, et ces bancs qui en reculent les bornes. Les rochers les plus durs, ces granits que les meilleurs outils ont tant de peine � fa�onner, ne r�sistent point au tems et aux intemp�ries des saisons; leur superficie se d�nature et se d�compose souvent au point de ne pas les reconno�tre: des lichens, des petites mousses s'insinuent dans leur tissu, l'eau y p�n�tre, et la gel�e s�pare leurs parties; s'ils se trouvent plac� sur une pente de fa�on � pouvoir �tre entra�n� par les eaux, la plus grosse masse est bient�t r�duite � peu de chose, apres avoir parcouru un plan inclin�; quels changemens ne doit pas avoir op�r� cette marche constante de la nature. A quel point n'est elle pas rendu m�connoissable la superficie du globe que nous habitons. Pour peu qu'on r�fl�chisse que les montagnes fournissent continuellement aux plaines, et que celle-ci ne rendent rien aux montagnes, on pourra se faire quelque id�e des changemens que la r�volution des si�cles � du op�rer. Aussi n'est ce que sur les hautes montagnes qu'on apper�oit encore parmi leurs vastes d�bris, les mat�riaux qui ont servi et servent aux cr�ations nouvelles que la nature op�re journellement, qu'ils sont grands, qu'ils sont majestueux ces antiques d�bris! que l'homme est petit, qu'il est confondu quand il ose y porter un regard curieux!�

In this picture of the Alps, there is presented to our view the devastation of solid rocks by agents natural to the surface of the earth; here is the degradation of mountains in the course of time. Of these ruins plains are formed below; and these plains are continually shifting their place, in affording materials to be washed away and rolled in the rivers, and in receiving from the higher grounds the spoils of ruined rocks and mountains. Such operations are general to the globe, or are to be found over all this earth; but it is not every where that we have descriptions proper to give just ideas of this subject, which escapes the common observation of mankind.

As I have given an example in the Alps of Savoy and Switzerland, it may be proper to give some view of the same operation in those of the Pyr�n�es (Essai sur la Min�ralogie des Monts Pyr�n�es) page 76.

�La vall�e d'Aspe est arros�e dans toute sa longueur, par le Gave, qui prend sa source vers les fronti�res d'Espagne: dans les temps de pluie et d'orage, cette rivi�re est color�e en rouge par des terres compos�es de schiste rouge�tre, qui s'�boulent: des montagnes de Gabedaille et de Peyren�re: au reste les eaux du Gave profond�ment encaiss�es dans leur lit ne peuvent plus contribuer � la fecondit� des plaines qu'elles ont form�es.

�On observe, en suivent cette rivi�re que lorsque les montagnes courent parall�lement, les angles faillans qu'elles forment correspondent aux angles rentrans; cette r�gle g�n�rale sert � �tablir que les vall�es des Pyr�n�es, qu'il faudroit plut�t appeler de gorges puisqu'elles n'ont qu'une demi-lieue dans leur plus grande largeur, sont l'ouvrage des eaux; mais doit on les ranger parmi celles que M. de Buffon a d�montr� avoir �t� creus�es par les courans de la mer, ou les supposer form�es par les torrens qui se pr�cipitent des montagnes?

�Ne croyez pas, dit M. d'Arcet, en faisant mention des vall�es des Pyr�n�es, que les eaux aient pris ces routes parce qu'elles les ont trouv�es fray�es ant�rieurement � leur cours; ce sont les eaux m�me d'en-haut, qui, se ressemblant peu-�-peu, se sont ouvert de force ces passages: elles se sont creus� ces lits dans le temps pass�s, comme elles les creusent encore tous les jours. Voyez la Discours sur l'�tat Actuel de Pyr�n�es, p.. 10.

(p. 86.) �Les pierres que les eaux du Val de Canfrac entra�nent, sont rarement us�es dans leurs angles; on en trouve peu dont la figure soit arrondie, comme celle des pierres que roulent les torrens de la partie septentrionale des Pyr�n�es; le sol des environs de Jacia, plus �lev� que celui des plaines du c�t� de la France, s'oppose a ce qu'elles soient emport�es � d'assez grandes distances, et avec la rapidit� necessaire pour recevoir, par un long frottement, une figure arrondie: on ne voit point de pierres roul�es dans les plaines qui entourent cette ville, les bancs calcaires ne sont couverts que d'une cro�te de terre peu �paisse; un telle formation diff�re de celle qu'on observe au pied des monts Pyr�n�es, du c�t� de la France, ou le sol de plusieurs contr�es est compos� des d�bris que les rivi�res y ont d�pos�s[6]; une partie de l'�gypte, selon H�rodote, a �t� pareillement form�e des mati�res que le Nil y a apport�es; Aristotle la nomme l'ouvrage du fleuve: c'est pourquoi les �thiopiens se vantoient que l'�gypte leur �toit redevable de son origine. Les habitans de Pyr�n�es pourroient dire la m�me chose de presque toutes les contr�es situ�es le long de la chaine septentrionale, depuis l'oc�an jusqu'� la M�diterran�e, et qui forment cette espace d'isthme qui s�pare les deux mers: c'est ainsi que la nature change continuellement la surface de notre globe; elle �l�ve les plaines, abaisse les montagnes; et l'eau est principal agent qu'elle emploie pour op�rer ces grandes r�volutions; il ne faut que du temps, pour que le mot de Louis XIV. � son petit-fils, se r�alise. La post�rit� pourra dire un jour; il n'y a plus de Pyr�n�es. On con�oit combien cette �poque est �loign�e de nous. M. Gensanne a trouv�, par des observations qu'il pretend non �quivoques, que la surface de ces montagnes baisse d'environ dix pouces par si�cle; ainsi, en les supposant seulement de quinze cens toises au-dessus du niveau de la mer, et toujours susceptibles du m�me degr� d'abaissement, il s'�coulera un million d'ann�es avant leur destruction totale.�

[Footnote 6: The notion, that the water-worn gravel, which we so frequently find upon the surface of the earth, had been the effect of rivers transporting the rocks and stones, is not accurate or in perfect science. That stones are thus continually transported is certain; it is also indisputable, that in this operation they are broken and worn by attrition, more or less; but, that angular stones of the hardest substance are thus made into that round gravel, which we find so abundantly in many places forming the soil or loose materials of the surface, is a conclusion which does not necessarily follow from the premises, so far as there is another way of explaining those appearances, and that by a cause much more proportioned to the effect.

The view which I take of the subject is this; first, that those water-worn materials had their great roundness from the attrition occasioned by the waves of the sea upon some former coast. Secondly, that, after having been thus formed by agitation on the shores, and transported into the deep, this gravel had contributed to the formation of secondary strata, such as the puddingstone which has been described in Part I. Chap 5, and 6; and, lastly that it has been from the decay and resolution of those secondary strata, in the wafting operations of the surface, that have come those rounded siliceous bodies, which could not be thus worn by travelling in the longest river.]

I do not know in what manner M. Gensanne made his calculation; I would suspect it was from partial, and not from general observations. We have mountains in this country, and those not made of more durable materials than what are common to the earth, which are not sensibly diminished in their height with a thousand years. The proof of this are the Roman roads made over some of those hills. I have seen those roads as distinct as if only made a few years, with superficial pits beside them, from whence had been dug the gravel or materials of which they had been formed.

The natural operation of time upon the surface of this earth is to dissolve certain substances, to disunite the solid bodies which are not soluble, but which, in having been consolidated by fusion, are naturally separated by veins and cutters, and to carry those detached bodies, by the mechanic force of moving water, successively from stage to stage, from places of a higher situation to those below.

Thus the beds of rivers are to be considered as the passages through which both the lighter and heavier bodies of the land are gradually travelling; and it is through them that those moveable bodies are from time to time protruded towards the sea shore. But, in the course of rivers, it often happens that there intervenes a lake; and this must be considered as a repository for heavy bodies which had been transported by the force of running water, in the narrow bed through which it was obliged to pass; for, being arrived in the lake, the issue of which is above the level of its bottom, the moving water loses its force in protruding heavy bodies, which therefore it deposits. Thus the bottom of the lake would be filled up, before the heavy materials which the river carries could be made to advance any farther towards the sea.

Reasoning upon these principles, we shall find, that the general tendency of the operations of water upon the surface of this earth is to form plains of lakes, and not, contrarily, lakes of plains. For example, it was not the Rh�ne that formed the lake of Geneva; for, had the lake subsisted in its present state, while the Rh�ne had transported all the matter which it is demonstrable had passed through that channel from the Alps, the bed of the lake must have been made a plain through, which the river would continue to pass, but in a changing channel, as it does in any other plain. We are therefore led to believe, that the passage of the Rh�ne through the lake, in its present state, is not a thing of long existence, compared with the depredations which time had made by that river upon the earth above the lake. But how far there are any means for judging, with regard to the causes of that change which must have taken place, and produced the present state of things about this lake, can only be determined by those who have the proper opportunity of examining that country.

If lakes are not in the natural constitution of the earth, when this is elevated from the sea into the place of land, they must be formed by some posterior operation, which may be now considered.

There are in nature, that is, in the natural operations of the globe, two ways by which a lake may properly be formed in a place where it had not before existed. One of these is the sliding or overshooting of a mountain or a rock, which, being undermined by the river, and pressed by its weight, may give way, and thus close up the defile through which the river had worn for itself a passage. The other is the operation of an earthquake, which may either sink a higher ground, or raise a lower, and thus produce a lake where none had been before. To which, indeed, may be added a third, the dissolution of saline or soluble earthy substances which had filled the place.

So many must have been those alterations upon the surface of the earth which we inhabit, and so short the period of history by which, from the experience of man, we have to judge, that we must be persuaded we see but little of those operations which make any sensible change upon the earth; and we should be cautious not to form a history of nature from our narrow views of things; views which comprehend so little of the effects of time, that they may be considered as nothing in the scale by which we are to calculate what has passed in the works of nature.

To form an idea of the quantity of the solid land which has been carried away from the surface of the earth, we must consider our land, with the view of a mineralist, as having all the soil and travelled materials removed, so as we might see the terminations of all the strata, where these are broken off and left abrupt. Now, the generality of those strata are declined from the horizontal plane in which they had been formed, and shew that the upper extremity had been broken off and carried away; and the quantity of that which has been carried away, since the time of the formation of those strata, so far as may be judged from the nature and situation of what remains, must be concluded as very great. This is best to be observed in mountainous countries, where not only the causes of this destruction of the land are more powerful, but the opportunities of investigating the effects more frequent, from the washing away of the loose soil or covering.

The correspondent angles of the valleys among mountains is a subject of this nature, in which may be perceived a visible waste of the solid mountain which has those correspondent angles. I am happy to have an authority so much better than my own observations to give on this occasion, where the question relates to what is common or general in these appearances. It is that of M. de Luc, Lettres Physique et Morales, tom. 2. p. 221. �Mais avant de finir sur les montagnes primordiales, il faut que je revienne � ces angles saillans et rentrans alternativement oppos�s, qui lorsque Mr. Bourguet les annon�a, firent un si grand bruit parmi les naturalistes qu'on ne douta plus que toutes les montagnes ne fussent l'ouvrage de la mer. Voici ce que c'est que ce ph�nom�ne pr�tendu d�monstratif.

�Lorsqu'on voyage dans les vall�es, on va ordinairement en tournoyant; et quand un angle saillant oblige � courber la route, on trouve assez souvent un angle rentrant qui lui fait face, et la vall�e conserve � peu pr�s la m�me largeur. M. Bourguet ayant fait cette remarque, et consid�rant que les bords oppos�s d'une rivi�re qui serpente, offrent la m�me opposition des angles saillans et rentrans, en conclut en g�n�ral, que les montagnes avoient �t� form�es par les courans de la mer.

�Si toutes les montagnes, et les Alpes par exemple, avoient tous les autres caract�res qu'exige une telle formation celui-l� sans doute ne paro�troit pas les contredire; et l'on ne peut m�me disconvenir, qu'au premier coup d'oeil, ces zig-zags ne ressemblent beaucoup aux effets des eaux courantes. Cependant ce caract�re appartient bien plus aux eaux qui se frayent une route, qu'� celles qui font des d�p�ts. Un rivi�re qui creuse son lit, se d�tourne � la rencontre d'un obstacle, et ronge le c�t� oppos�; c'est ce qui produit ses m�andres. Mais on ne voit point les m�mes causes de zig-zags dans les courans au sein de la mer; � moins qu'il n'y ait d�j� des montagnes.

�En effet si l'on consid�re les montagnes et les collines qui par leurs couches et les corps �trangers qu'elles renferment, montrent sans �quivoque qu'elles sont l'ouvrage des eaux, on les trouvera le plus souvent rang�es sans ordre. Quelquefois elles ne paroissent que des monceaux pos�s �� et l�; comme dans une grand partie du Pi�mont. Ou si elles sont sous la forme de cha�nes continues, on y trouve peu de parall�lisme, c'est-�-dire de ces angles rentrans oppos�s aux angles saillans: tel est le Jura.

�Mais si les courans de la mer ont trouv� des montagnes toutes faites, et qu'ils les ayent travers�es, dans quelque sens que ce soit; ils se sont fray� des routes dans les endroits o� la resistance �toit moindre, et ont rong� les bords de leurs canaux � la mani�re des rivi�res. On doit donc y trouver du parall�lisme.

�Si maintenant on consid�re la cha�ne des Alpes, on verra qu'elle r�pond fort bien � cet effet naturel. Quoique ces montagnes forment une cha�ne dans leur ensemble, leurs parties sup�rieures ne montrent aucune sorte d'arrangement particulier, aucune trace de zig-zags: c'est dans le fond des grandes vall�es, ou dans les coupures qui servent � l'�coulement des eaux, que ce parall�lisme des c�t�s oppos�s se remarque; quoiqu'avec bien des exceptions. Et ce qu'il y a de plus important � consid�rer, c'est que ces grandes vall�es ou les angles saillans et rentrans forment l'engr�nement le plus sensible, coupent ordinairement la cha�ne en travers, au lieu de la suivre; ce qui annonce plut�t destruction qu'�dification.

�Ainsi les angles saillans et rentrans alternativement opposes dans les vall�es des montagnes, peuvent bien contribuer � prouver qu'elles ont �t� toutes sous les eaux de la mer; mais non que la mer les a�t toutes faites. C'est ici donc un nouvel exemple de la n�cessit� de consid�rer attentivement les id�es qui paroissent le plus naturelles au premier coup d'oeil: car cet aper�u �toit bien un de ceux qu'on est tent� d'admettre sans examiner autre chose que la v�rit� du fait.�

Here we have the testimony of this author concerning the nature of those causes by which the shape of the surface of the earth, in those regular appearances of corresponding parts, had been determined, viz. That these had been destroying operations, and not those by which the mountains had been formed. We differ, however, from this naturalist with regard to the particular agent here employed. It will be shown, in a subsequent chapter, that there is almost as little reason to conclude from this appearance, that the space between the correspondent angles had been hollowed by the currents of the sea, as that those angles had been formed by matters deposited in that shape and situation.

Farther, treating of the calcareous mountains, the same author observes, (Lettre 38. p. 229.)

�Cette cha�ne ext�rieure des Alpes �videmment d'origine marine, a cependant des caract�res qui la distinguent de la plupart des autres montagnes de la m�me classe; et ces caract�res semblent annoncer plus d'antiquit�. Je crois d'abord pouvoir les regarder comme les montagnes secondaires les plus hautes de notre continent. (Je ne parle ici que des montagnes marines.) Ensuite leur destruction est beaucoup plus grande que celle d'aucune autre montagne de ce genre qui me soit connue: car elles sont presque aussi couronn�es de pics que les Alpes primordiales; et ces pics, �tant par couches, montrent des restes d'anciens sommets qui devoient avoir une grande �tendue. Ce qui, joint � quelques d�rangemens dans leurs couches, paro�t indiquer que ces montagnes ont �t� expos�es plus longtemps que la plupart des autres montagnes secondaires, aux revolutions qu'essuyoit le fond de la mer; et qu'elles en sont sorties d�j� fort alt�r�es.�

There is at present no question concerning the particular shape in which the mountains of the earth had come out of the waters of the sea. We are considering the wasting of those mountains, in being exposed to the atmosphere and waters of the earth; and the operation that the sea may have had upon their surface, is a subject for judging of which we have not the smallest data, unless by taking the thing for granted, or supposing that the present state of things is that former shape after which we inquire. Now, this is a species of reasoning that M. de Luc would certainly explode; for he admits, as we shall afterwards find, great changes among the mountains of the Alps, from the influences of the atmosphere, perhaps more rapid changes than we are disposed to allow. Therefore, to call in the aid of the ocean, for the degradation of these secondary calcareous mountains, holds of no reason that I can see, unless it be that of diminishing the time which otherwise would have been required in bringing about those changes by the atmosphere alone.

To conclude: Whether we examine the mountain or the plain; whether we consider the degradation of the rocks, or the softer strata of the earth; whether we contemplate nature, and the operations of time, upon the shores of the sea, or in the middle of the continent, in fertile countries, or in barren deserts, we shall find the evidence of a general dissolution on the surface of the earth, and of decay among the hard and solid bodies of the globe; and we shall be convinced, by a careful examination, that there is a gradual destruction of every thing which comes to the view of man, and of every thing that might serve as a resting place for animals above the surface of the sea.

I have distinguished the mineral operations of the earth, by which solid bodies are formed of loose materials, as well as the resolving or decomposing operations which are proper to the surface exposed to the sun and atmosphere. I have also pointed out the end or intention of those several operations, and likewise the means by which they have been brought about. We may now turn our view to that part of the system in which an indefinite variety of soils, for the growth of plants and life of animals, is to be provided upon the face of the earth, corresponding to that diversity which, in the wisdom of nature, has been made of climates.

In this last view, now to be considered, some confirmation should be given to the Theory, in finding the soil, or travelled materials upon the surface of the land, composed of earth, that is, of sand and clay, of stones and gravel; the earth and stones as arising from the resolution and separation of the solids in the neighbourhood of the place; the gravel, again, as having often travelled from more distant parts.

It would be very improper to adduce any example of a particular, where the force of the argument lies in the generality alone. It is enough to have mentioned the facts which are to be examined: Every person of inquiry and observation will judge for himself how far those facts are true.

But there is one general remark that may be made on this occasion, where the operations of the surface are concerned, and which may assist the investigation of this subject; it is with regard to the gravel or stones worn by attrition, which may have come from a distance. In proportion as hard and insoluble stones are near to their natural beds, they will be found with the sharp angles of their fracture, unless there may have been a cause of agitation and attrition on the spot; they will also be in greater quantity, cet. par. in this place; whereas the farther they may have travelled, they will naturally incline to be more rounded, and, in equal circumstances, will always be more scarce.

We have thus principles by which to judge of every appearance in relation to the travelled materials of our soil. When, for example, we find an immense quantity of the hardest stones worn round by attrition, and collected not far distant from their native place, we cannot suppose that they have acquired their shape by the attrition in the distance they have travelled, but in an agitation which they must have received nearly in the place from whence they came. Such is the gravel in the chalk country of England. Around London, in all directions, immense quantities of gravel are round, which consists almost entirely of flint worn or rounded by attrition; but this is the very centre of the chalk country, at least of England; and no doubt the same appearances will be found in France. We must therefore conclude, that the south of England was under water when that gravel was formed; and that immense quantities of the chalk above had been destroyed by the agitation of the sea in preparing such quantities of gravel which still remain upon the land; besides the immense quantities which must have been dispersed all around during the operation, as well as carried into the sea by the rivers since the elevation of our land. It is not uncommon to find this gravel twenty or thirty feet deep; and masses are found of much greater thickness. Were these masses of gravel formed in a deep hollow place, they would draw to no conclusion beyond the appearance itself; but they are, on the contrary, in form of hills; and therefore they serve as a kind of measure or indication of what had been carried away when these were left remaining.

We may observe a series or a progress in those forming and destroying operations, by which, on the one hand, the flinty bodies, already formed in the mineral region, were again destroyed, in being diminished by their mutual attrition; and, on the other hand, those diminished bodies were again consolidated into one mass of flinty stone, without the smallest pore or interstice. This example is to be found in the puddingstone of England. It consists of flint pebbles, precisely like Kensington gravel, penetrated or perfectly consolidated by a flinty substance. Here are the two opposite processes of the globe carried on at the same time and nearly in the same place. But it must be considered, that our land was then in the state of emerging from the sea, and those operations of subterranean fire fit for elevating land was then no doubt exerted with great energy; at present, no such thing appears in this place. But, from the momentary views we have of things, it would be most unphilosophical to draw such absolute conclusions.

The argument now employed rests upon the identity of the substance of the gravel with that of the entire flint, which is found in the chalk country; and it goes to prove that the sea had worn away a great deal of that chalk country above the place upon which this body of gravel is now resting; consequently that the sea had formerly flowed over that country covered with gravel, and had dispersed much of that gravel in transporting it to other regions, where that species of flint was not naturally produced. By a parity of reasoning, the gravel produced in the neighbouring regions, and which would be proper to those places, as consisting of their peculiar productions, must have been likewise dispersed and mixed with the surrounding bodies of gravel. But as in the country of which we are now treating, there are considerable regions, the different productions of which are perfectly distinct, we have a proper opportunity of bringing those conclusions of the theory to the test of observation.

For this purpose, let us examine the different countries which surround the chalk regions of England, France, and Flanders; if the gravel upon those neighbouring countries contain flint which the country does not naturally produce; and if the mixture of this flint among the gravel, which is proper to the country itself, be with regard to quantity in proportion to the vicinity of the flint country, the Theory will then be confirmed; and there is no doubt that this is so. On the other hand, let us examine the gravel about London, which is far distant from any place that produces quartz; if we shall find a very small proportion of quartz gravel in this flinty soil, we may be assured that the quartz has travelled from a distance, and that the Theory is thus approved. This is actually the case, and I have seen puddingstone containing quartz gravel among the flint.

In confirmation of this view of the travelled soil, it may be observed, that in lower Saxony about Hamburgh, and for a great way to the south-west, the gravel is mostly of broken flint, such as is around the chalk countries: Yet it is at a distance from the chalk of Flanders; there is however at Luxemburgh chalk with flint, the same as in England and France. Therefore the flinty soil of that country, in like manner, demonstrates the great destruction of the solid parts, and illustrates the formation of soil by the remainder of the hard parts below, and the alluvion of other parts.

There is most undoubted evidence that the solid body of our land had been formed at the bottom of the sea, and afterwards raised above the surface of the water; but, in the case which has now been described, it appears that the travelled soil of the surface of our land had been lately under the surface of the sea. We have thus therefore traced the different steps in the operations of nature, of which the last step may be considered as thus exposed to our view almost as much as the operations of man in building the Pyramids of Egypt. But surely there are other documents to be found in examining the different coasts of this island with attention; and there must be a consistency in the general appearance which never fails to attend on truth.

From the south to the north of this island, there are, in many places, the most evident marks of the sea having been upon a higher level on the land; this height seems to me to amount to about 40 or 50 feet perpendicular at least, which the land must have been raised. Some of those facts may now be mentioned.

Upon the banks of the Thames, I have found sea shells in the travelled soil a considerable height above the level of the sea. In low Suffolk there are great bodies of sea shells found in the soil which the farmers call crag, and with it manure their land. I do not know precisely the height above the sea; but I suppose it cannot exceed 100 feet. In the Frith of Forth there are, in certain places, particularly about Newhaven, the most perfect evidence of a sea bank, where the washing of the sea had worn the land, upon a higher level than the present. The same appearance is to be found at Ely upon the Fife coast, where the sea had washed out grottos in the rocks; and above Kinneel, there is a bed of oyster shells some feet deep appearing in the side of the bank, about 20 or 30 feet above the level of the sea, which corresponds with the old sea banks. I have seen the same evidence in the Frith of Cromarty, where a body of sea shells, in a similar situation, was found, and employed in manuring the land. There are many other marks of a sea beach upon a higher level than the present, but I mention only those which I can give with certainty.

We have been considering an extensive country more or less covered with gravel; such is England south of Yorkshire; both upon the east and west sides of the island. This country having no high mountainous part in the middle, so as to give it a considerable declivity towards the shores and rivers, the gravel has remained in many places, and in some parts of a considerable thickness. But in other parts of the island, where the declivity of the surface favours the transportation of gravel by the currents of water, there is less of the gravel to be found in the soil, and more of the fragments of stone not formed into gravel. Still, however, the same rule holds with regard to tracing the gravel from its source, and finding particular substances among the gravel of every region, in proportion to the quantity of country yielding that substance, and the vicinity to the place from whence it came.

Here are principles established, for the judging of a country, in some respects, from a specimen of its gravel or travelled stones. In this manner, I think, I can undertake to tell from whence had come a specimen of gravel taken up any where, at least upon the east side of this island. Nor will this appear any way difficult, when it is considered, that, from Portland to Caithness or the Orkneys, there are at least ten different productions of hard stone in the solid land which are placed at proper distances, are perfectly distinguishable in the gravel which is formed of them, and with all of which I am well acquainted. Let us suppose the distance to be 600 miles, and this to be divided equally into 10 different regions of 60 miles each, it must be evident that we could not only tell the region, which is knowing within 60 miles of the place, but we could also tell the intermediate space, by seeing an equal mixture of the gravel of two contiguous regions; and this is knowing within 30 miles of the place. If this be allowed, it will not seem difficult to estimate an intermediate distance from the different proportions of the mixed gravel. This is supposing the different regions to be in all respects equal, which is far from being in reality the case; nevertheless, a person well acquainted with the different extent and various natures of those regions, may make allowances for the different known circumstances that must have influenced in those operations, although it is most probable there will be others which must be unknown, and for which he can make no allowance.

The author of the Tableaux de la Suisse has entered very much into this view of things; he has given us some valuable observations in relation to this subject, which I would here beg leave to transcribe[7].

[Footnote 7: Discours sur l'Histoire Naturelle de la Suisse, p. 27.]

�Nous avons dit pr�c�demment que c'�toit entre Orfi�re et Liddes que nous avions vu les derniers granites roul�s, on n'en rencontre plus dans tout le reste de la route jusqu'au haut du Mont St. Bernard. Les rochers qui dominent ce sommet ne sont pas compos�s de granites, et quoiqu'on ne puisse aborder jusqu'� leur plus grande �l�vation, on peut juger de leurs esp�ces, par les masses qui s'en pr�cipitent. D'o� peuvent donc provenir ces masses roul�es de granites qui se trouvent jet�s et r�pandus sur le penchant et au bas de ce mont? Il y a peut-�tre quelque montagne ou rocher de granite que nous n'avons pas �t� � port�e de voir: il faudroit plus d'un mois pour faire un pareil examen et parcourir les montagnes environnantes, et faute de pouvoir parvenir � certains sommets, examiner scrupuleusement les fonds pour juger des hauts. De pareilles recherches sont plus difficiles et plus longues qu'on ne le croit communement quand on veut r�ellement voir et observer. Beaucoup de vallons sont combl�s � des hauteurs prodigieuses, par les amas et les d�bris provenant des montagnes sup�rieures: ils cessent d'�tre des vallons, pour former ou faire partie de montagnes. Ces d�placement et des bouleversemens, changeant la direction et le courant des torrens, entra�nent dans des parties bien oppos�es des d�bris qu'on croiroit devoir chercher et trouver ailleurs. On seroit induit en erreur, en voulant suivre toujours le cours actuel des eaux qui descendent des montagnes. Ce n'est pas dans cette occasion seul mais l'Allemagne, la Corse, la Sardaigne, et beaucoup de pays de hautes montagnes, nous out fourni �galement des exemples de masses de rochers roul�s de diff�rentes esp�ces dont il n'existoit pas de rochers pareils, dans toutes les parties �lev�es environnantes, � plusieurs lieues, � plusieurs journ�es de chemin, et souvent totalement inconnus dans les pays d'alentour. Si nous avons remarqu� les m�me esp�ces de rochers faisant corps, et attach�s au sol, � une ou plusieurs lieues de distance; nous avons vu souvent que des montagnes plus hautes �toient entre ces masses roul�es et les rochers, d'ou on auroit pu supposer qu'elles ont �t� arrach�es: il repugne � croire que des masses, d'un poids prodigieux, ayent �t� transport�es et roul�es en travers d'un vallon profond, pour remonter et passer de l'autre c�t� d'une montagne. Nous abandonnons, a ceux qui travaillent dans le cabinet, � l'arrangement du globe, la recherche des moyens que la nature a employ� pour produire de pareils effets. Nous nous contenterons, ainsi que nous avons promis, de rendre compte de ce que nous avons vu et observ�, et d'engager ceux qui auront la facilit� de faire des remarques analogues de constater leurs observations en indiquant toujours les lieux fid�lement, ainsi que nous le faisions pour la Suisse.�

Here the experience of our naturalist amounts to this, that, in those operations by which the solid land is wasted, and the hard materials worn by attrition and transported, it is not always evident from whence had come every particular body of stone or mineral which had travelled by means of water; nor the particular route which, in descending from a higher to a lower place, the protruded body had been made to take, although, in general, these facts may be discovered without much difficulty. Now, this state of things is no other than the natural consequence of the great wasting of the surface and solid parts of our land, and the unequal degradation of this surface, by which means the shape of the earth is so changed, that it would often be impossible, from the present state, to judge of the course in which many bodies had been travelled by water.

M. de Saussure has described a very curious appearance of this kind: It is the finding the travelled materials of Mont Blanc, or fragments detached from the summit and centre of the Alps, in such places as give reason to conclude that they had passed through certain openings between the mountains of the Jura. This is a thing which he thinks could not happen according to the ordinary course of nature; he therefore ascribes this appearance to some vast debacle, or general flood, which had with great impetuosity transported all at once those heavy bodies, in the direction of that great current, through the defiles of the Alps, or the openings of those mountains.

In giving this beautiful example of the wasting and transporting operations of this earth, this naturalist overlooks the principles which I would wish to inculcate; and he considers the surface of the earth, in its present state, as being the same with that which had subsisted while those stones had been transported. Now, upon that supposition, the appearances are inexplicable; for, How transport those materials, for example, across the lake of Geneva? But there is no occasion to have recourse to any extraordinary cause for this explanation; it must appear that all the intervening hollows, plains, and valleys, had been worn away by means of the natural operations of the surface; consequently, that, in a former period of time, there had been a practicable course in a gradual declivity from the Alps to the place where those granite masses are found deposited. In that case, it will be allowed that there are natural means for the transportation of those granite masses from the top of the Alps, by means of water and ice adhering to those masses of stone, at the same time perhaps that there were certain summits of mountains which interrupted this communication, such as the Jura, etc. through the openings of which ridges they had passed.

In this case of blocks of alpine stones upon the Jura, the question is concerning the transportation of those stones; but, in other cases, the question may be how those blocks were formed.

That many such blocks of stone are formed by the decay of the rock around them, is clearly proved by the observations of M. Hassenfratz, published in the Annales de Chimie, October 1791. He has particularly mentioned a place on the road from Saint-Flour to Montpellier, where an amazing collection of these blocks of granite is to be seen. It is here particularly that he observes these blocks to be the more durable parts which remain after the rock around them is decayed and washed away. The proof is satisfactory; the operation is important to the present theory; and therefore I shall give it in his own words.

�Tous les blocs de granit dur d�gag�s et sortis enti�rement des masses qui forment les montagnes, posent imm�diatement sur le granit friable ou sur d'autres blocs durs qui eux-m�mes sont sur le granit friable.

�Quoique la plupart des blocs de granit dur, que l'on observe sur toute l'�tendue de ce terrain granitique, soient enti�rement sortis et d�gag�s de la masse de pierre qui forme la montagne, on en rencontre cependant qui ne sont pas encore tout-�-fait d�gag�s. Et c'est ici l'observation essentielle qui conduit directement � l'explication du ph�nom�ne de l'arrangement, de l'entassement, et de l'amoncellement des blocs d'une mani�re simple et absolue.

�On voit sur la surface du terrain des portions de blocs durs qui semblent sortir peu � peu, et se d�gager de la masse de granit friable; celui-ci se d�compose et se r�duit en poussi�re tout autour de cette masse dure que les causes de d�composition du granit friable semblent respecter.

�Quelques-uns de ces blocs durs, sortans de la montagne granitique, sont d�j� consid�rable; on distingue qu'ils n'y tiennent plus que par une tr�s-petite partie; d'autres commencent � paro�tre se d�gager, ils ne saillent, ils ne sortent encore que de quelque pieds, et m�me de quelques pouces. Enfin, en examinant soigneusement et attentivement toute la surface de ce terrain granitique, on apper�oit tous les interm�diaires entre un bloc de granit dur contenu et enchass� dans la masse totale du granit friable et un bloc enti�rement d�gag�.

�Ces observations, suivies avec attention, ne laissent aucun doute que les blocs de granit que l'on observe sur toute l'�tendue de ce terrain granitique, n'aient fait autrefois partie d'une couche consid�rable de granit d�composable qui couvroit ces montagnes et exhaussoit leur sol; que cette couche, dont il semble impossible d'appr�cier la hauteur, malgr� les blocs consid�rable qui restent et qui attestent son existence, a �t� d�compos�e par l'air et l'intemp�rie des saisons; que la poussi�re, le sable r�sultans de cette d�composition, ont �t� entra�n�s par les eaux, et d�pos�s � divers points de la surface de la globe; et que ces blocs ont �t� peu-�-peu d�gag�s de la couche, ainsi qu'il s'en d�gage encore tous les jours.�

To enable the reader to form a notion of what these blocks are, I shall farther give what our author has said in describing this place where they are found.

�C'est apr�s avoir quitt� le terrain volcanique, c'est dans le terrain granitique que j'ai trouv� des blocs �normes de granit, qui ont fix� mon attention.

�Toute l'�tendue du terrain granitique que j'ai travers�e, se trouve presque couverte de ces masses; les uns sur les sommets des montagnes les plus �lev�es, les autres sur la pente et dans les vall�es. Plusieurs de ces masses sont arrang�es les uns sur les autres avec un art inimitable, les autres sont isol�es et �parses.

�Peu de ces masses m'ont pr�sent� un spectacle plus beau et plus imposant que celles que l'on rencontre � 6 heures de marche de S. Flour, � une petite demi heure avant d'arriver � la Garde.

�L�, sur le sommet d'une montagne, est un amas consid�rable de blocs de granit, �tonnans par leur volume et leur nombre. La grande route passe � travers, et circule autour de ces masses que les constructeurs des chemins n'ont pas os� attaquer.

�Le voyageur est p�n�tr� d'admiration en voyant l'ordre et l'arrangement sym�trique de ces blocs monstrueux par leur masse, et qu'il ne cesse d'observer en suivant la trace tortueuse du chemin qui les contourne.

�Quelques-uns de ces blocs sont pos�s purement et simplement les uns sur les autres, et forment une colonne isol�e; le plus gros sert de base, et les autres, graduellement plus petits, son pos�s dessus. On voit jusqu'� trois de ces blocs imm�diatement l'un sur l'autre.

�D'autres fois, le bloc qui sert de base est beaucoup plus petit que celui qui le couvre imm�diatement; et s'arrangement de ces deux blocs pr�sente l'aspect d'un champignon.

�Plus souvent plusieurs blocs s�par�s les uns des autres, forment la base, et un ou plusieurs blocs sont pos�s imm�diatement dessus, sans ordre constant, tant�t inclin�s, mais toujours d'une mani�re stable et fixe, propre � resister aux plus grands efforts.

�Enfin, par fois, des masses plus petites plac�es entre les grosses, semblent assurer la situation fixe de l'ensemble des blocs; mais ces rencontres sont fort rares.�

Here is a distinct view of this part of nature; a view in which the present state of things plainly indicates what has passed, without our being obliged to raise our imagination to so high a pitch as is sometimes required, when we take the mountains themselves, instead of these blocks, as steps of the investigation. Here is a view, therefore, that must convince the most scrupulous, or jealous with regard to the admitting of theory, first, that those mountains had been much higher; secondly, that they had been degraded in their present place; thirdly, that this continent has subsisted in its present place for a very long space of time, during the slow progress of those imperceptible operations; and, lastly, that much of the solid parts of this earth has been thus travelled by the waters to the sea, after serving the purpose of soil upon the surface of the land.

But though M. Hassenfratz has thus given us a most satisfactory view of the natural history of those blocks of stone which are now upon or near their native place, this will not explain other appearances of the same kind, where such blocks are found at great distances from their native places, in situations where the means of their transportation is not to be immediately perceived, such as those resting upon the Jura and Saleve, and where blocks of different kinds of stone are collected together. These last examples are the records of something still more distant in the natural history of this earth; and they give us a more extensive view of those operations by which the surface of this earth is continually changing. It is, however, extremely interesting to this Theory of the Earth, to have so distinctly ascertained some of those first steps by which we are to ascend in taking the more distant prospect; and these observations of M. Hassenfratz answer this end most completely.

Thus all the appearances upon the surface of this earth tend to show that there is no part of that surface to be acknowledged as in its original state, that is to say, the state in which it had come immediately from the mineral operations of the globe; but that, every where, the effects of other operations are to be perceived in the present state of things. The reason of this will be evident, when we consider, that the operations of the mineral kingdom have properly in view to consolidate the loose materials which had been deposited and amassed at the bottom of the sea, as well as to raise above the level of the ocean the solid land thus formed. But the fertility of the earth, for which those operations were performed, and the growth of plants, for which the surface of the earth is widely adapted, require a soil; now the natural, the proper soil for plants, is formed from the destruction of the solid parts. Accordingly, we find the surface of this earth, below the travelled soil, to consist of the hard and solid parts, always broken and imperfect where they are contiguous with the soil; and we find the soil always composed of materials arising from the ruin and destruction of the solid parts.

There is not perhaps one circumstance, in the constitution of this terraqueous globe, more necessary to the present theory, than to see clearly that the solid land must be destroyed, in undergoing the operations which are natural to the surface of the earth, and in serving the purposes which are necessary in the system of this living world. For, all the land of the present earth being a certain composition of materials, perfectly similar to such as would result from the gradual destruction of a continent in the operations of the inhabited world, this composition of our land could not be explained without having recourse to preternatural means, were there not in the constitution of this earth an active cause necessarily, in the course of time, destroying continents.

It is therefore of great importance to this Theory, to show, that the land is naturally wasted, though with the utmost economy; and that the continents of this earth must be in time destroyed. It is of importance to the happiness of man, to find consummate wisdom in the constitution of this earth, by which things are so contrived that nothing is wanting, in the bountiful provision of nature, for the pleasure and propagation of created beings; more particularly of those who live in order to know their happiness, and who know their happiness on purpose to see the bountiful source from whence it flows.

We are to conceive the continent of the earth, when first produced above the surface of the ocean, to be in general consolidated, with regard to its structure, by the same mineral operations which are necessarily employed in raising it from its primary situation at the bottom of the sea, to that in which we now inhabit it.

We are now to consider the purpose of this mineral body, exposed to the influences of the atmosphere, that so we may see the intention of its solid composition, as well as that of its resolution, or natural solubility when thus exposed; and we are to trace the ultimate effects of this order of action in the economy of the globe, that so we may perceive the wisdom of nature perpetuating the system of a living world in an endless succession, of changing perishable forms.

The purpose of the land of this earth, in being placed above the sea and immersed in the atmosphere, is to sustain a system of plants and animals. But; for the purpose of plants; there is required a soil; and, as there is in the vegetable system a vast variety of plants with different habits or natural constitutions, there is also required a diversity of soils, in which those vegetable bodies are to be made to live and prosper. From the bare rock exposed to the sun and wind, to the tender mud immersed in water, there is a series to be observed; and in every stage or step of this gradation, there are plants adapted to those various soils or situations. Therefore nothing short of that diversity of soils and situations, which we find upon the surface of the earth, could fulfill the purpose of nature, in producing a system of vegetables endued with such a diversity of forms and habits.

The soil or surface of this earth is no more properly contrived for the life and sustenance of plants, than are those plants for that diversity of animals, which will thus appear to be the peculiar care of nature in forming a world. Scarce a plant perhaps that has not its peculiar animal which feeds upon its various productions; scarce an animal that has not its peculiar tribe of plants on which the economy of its life, its pleasure, or its prosperity must depend.

If we shall suppose the continent of our earth to be a solid rock, on which the rain might fall, and the wind and waves might dash perpetually, without impairing its mass or changing its constitution, what an imperfect world would we have! how ill adapted to the preservation of animal and vegetable life! But the opposite extreme would equally frustrate the intention of nature, in producing bounteously for the various demands of that multiplicity of species which the author of this world has thought proper to produce.

For if, instead of a solid rock, we shall suppose a continent composed of either dry sand or watery mud, without solidity or stability, how imperfect still would be that world for the purpose of sustaining lofty trees and affording fruitful soils!

We have now mentioned the two extreme states of things; but the constitution of this earth is no other than an indefinite number of soils and situations, placed between those two extremes, and graduating from the one extreme, in which some species of animals and plants delight in finding their prosperity, to the other, in which another species, which would perish in the first, are made to grow luxuriantly. That is to say, the surface of this earth, which is so widely adapted to the purpose of an extensive system of vegetating bodies and breathing animals, must consist of a gradation from solid rock to tender earth, from watery soil to dry situations; all this is requisite, and nothing short of this can fulfil the purpose of that world which we actually see.

We have been representing this continent of our earth as coming out of the ocean a solid mass, which surely it is in general, or in a great degree; but we find the surface of this body at present in a very different state; and now it will be proper to take a view of this change from solid rock to fertile soil.

Upon this occasion I shall give the description of nature from the writings of a philosopher who has particularly studied this subject. It is true that M. de Luc, who furnishes the description, draws, from this process of nature, an argument for the perpetual duration or stability of mountains; and this is the very opposite of that view which I have taken of the subject; but as, in this operation of nature producing plants on stones, he allows the surface of the solid stone to be changed into earth and vegetables, it is indifferent to the present theory how he shall employ this earth and vegetable substance, provided it be acknowledged that there is a change from the solid state of rock to the loose or tender nature of an earth, from the state of a body immovable by the floods and impenetrable to the roots of plants, to one in which some part of the body may be penetrated and removed.

[8]�Les pluies et les ros�es forment partout o� elles s�journent, des d�p�ts qui sont la premi�re source de toute v�g�tation. Ces d�p�ts sont toujours m�l�s des semences des mousses, que l'air charie continuellement, et auxquelles se joignent bient�t les semences presque aussi abondantes des gramens, qui sont l'herbe dominante de nos prairies. Ainsi partout o� la pluie a form� quelque petit d�p�t, il cro�t de la mousse ou des gramens. Ceux-ci demandent un peu plus de terre v�g�tale pour cro�tre, ils germent, et se conservent principalement dans les intervalles et les creux des pierres: mais la mousse cro�t bient�t sur la surface la plus unie. Il n'est aucune pierre long-temps expos�e � l'air, qui soit parfaitement polie; l'action de l'air, du soleil, des eaux, des gel�es, detruiroit ce poli quand il existeroit. Le moindre creux alors re�oit un d�p�t de la pluie, et nourrit un brin de mousse, ces brins poussent des racines; et de nouveaux jets autour d'eux, qui contribuent � arr�ter l'eau de la pluie et de la ros�e, et par ce moyen � arr�ter les d�p�ts Nourriciers.�

[Footnote 8: Histoire de la Terre, Tom. 2. page 26.]

�Quand la mousse a multipli� ses filets, les d�p�ts s'augmentent plus rapidement encore; les brins de la mousse, en s�chant et pourrissant, en forment eux-m�mes; car leur substance n'�toit que ces m�mes d�p�ts fa�onn�s: d'autres semences charri�es par l'air, qui au-paravant glissaient sur les pierres, parce que rien ne les retenoit, tombent dans le fond de la mousse, et y trouvent l'humidit� n�cessaire pour produire leurs premi�res racines: celles-ci s'entrelassent dans la mousse, o� elles se conservent � l'abri du soleil, et sont alors autant de petites bouches qui pompent les sucs, que l'air, les pluies, et les ros�es y d�posent. Ces premi�res plantes sont foibles, quelque fois m�me elles ne parviennent pas � leur perfection: mais elles ont contribu� � fixer la terre v�g�table. En s�chant et se d�composant, elles se transforment en cette terre, qui tombe au fond de la mousse, et qui pr�pare ainsi de la nourriture pour de nouvelles plantes qui alors prosp�rent et fructifient.

�Nous connoissons peu encore ce que c'est que cette terre v�g�table, ce d�p�t des pluies ou en g�n�ral de l'air. Cependant, en rassemblant les ph�nom�nes, on peut conjecturer, que la plupart des corps terrestres sont susceptibles d'�tre chang�s en cette substance, et qu'il ne s'agit pour cette transformation que de les d�composer. J'entends par l� une telle division de leurs parties, que devenant presque des �l�mens, elles puissent �tre intimement m�l�es � l'eau, et pomp�es avec elle par les tuyaux capillaires des plantes. En un mot, il semble suffisant qu'une mati�re puisse entrer en circulation dans les v�g�taux, pour qu'elle serve � en d�velopper le tissu, et qu'elle y prenne la figure et les qualit�s que chacun de ces laboratoires est propres � produire.

�Nous pouvons acc�l�rer de bien des mani�res la transformation des mati�res terrestres en terre v�g�table. La fermentation, la calcination, une plus grande exposition � l'air, diff�rens m�langes, rendent propres � la v�g�tation, des mati�res qui ne l'�toient par elles-m�mes: voila ce que peuvent nos soins. Mais l'air travaille sans cesse et en mille mani�res. Son simple frottement sur tous les corps, en enl�ve des particules si att�nu�es que nous ne les reconnoissons plus. La poussi�re de nos appartemens en est peut-�tre un exemple. De quelque nature que soient les corps dont elle se d�tache, c'est une poudre gris�tre qui semble �tre partout la m�me. La formation de la terre v�g�table a probablement quelque rapport � celle-l�. Toute la surface de la terre, les rocs les plus durs, les sables et les graviers les plus arides, les m�taux m�me, �prouvent l'action rongeante de l'air et leurs particules att�nu�es, d�compos�es, recompos�es de mille mani�res, sont probablement la source principal de la v�g�tation. L'air lui-m�me ainsi que l'eau, s'y combinent: beaucoup d'observations et d'exp�riences nous prouvent que ces deux fluides fournissent leur propre substance aux parties solides des v�g�taux, et par cons�quent � la terre v�g�table qui les produit et qu'ils d�posent. Quantit� de plantes se nourrissent de l'eau seule, et nous laissant cependant en se s�chant, un r�sidu de mati�re solide permanente. L'air aussi se fixe dans les corps terrestres, il fait partie de leur substance solide; les chimistes savent de plus en plus, et le fixer, et lui redonner son �lasticit� primitive, par divers proc�d�s: et avant la multitude d'exp�riences qui se sont de nos jours sur cet objet int�ressant de la physique, le Dr. Hales avoit montr�, que les v�g�taux renferment une tr�s-grande quantit� d'air, qui s'y trouve sans ressort et comme mati�re constituante.

�Voila donc probablement les sources o� la nature puise peu � peu la terre v�g�table dont elle recouvre la surface de nos continens. Ce sont les particules, peut-�tre, de tous les corps tant solides que fluides, extraites ou fix�es par des proc�d�s qui les rapprochent de leurs premiers �l�mens, et leur font prendre � nos yeux une m�me apparence. Ces particules sont ainsi rendues propres � circuler dans les semences des plantes, � en �tendre le tissu � y prendre toutes les propri�t�s qui caract�risent chaque esp�ce, et � les conserver tant que la plante existe. Ces m�mes particules, apr�s la destruction des plantes, prennent le caract�re g�n�ral de terre v�g�table, c'est-�-dire de provision toute faite pour la v�g�tation.

�Les plus petits recoins des montagnes, qui peuvent arr�ter l'eau de la pluie, sont certainement fertilis�s; ce ne sont pas seulement les grandes surfaces plates, ni les pentes; ce sont m�me les faces escarp�es des rochers les plus durs. S'il s'y fait quelque crevasse, un arbre s'y �tablit bient�t; et souvent il contribue, par l'accroissement de ses racines, � acc�l�rer la chute du lambeau de rocher qui l'avoit re�u. S'il y a quelque petite terrasse, ou seulement quelque partie saillante grande comme la main, elle est bient�t gazonn�e. Les plus petites sinuosit�s se peuplent de plantes; et les surfaces les plus unies, celles m�mes qui sont tourn�es vers la bas, re�oivent au moins quelqu'une de ces mousses plates, nomm�s lichen par les botanistes, qui ne font en apparence que passer une couleur sur la pierre. Mais cette couche est �caill�e, et elle loge bient�t de petites plantes dans ses replis; de celles qui veulent l'ardeur du soleil, si le rocher est au midi, ou la fra�cheur de l'ombre, s'il est au nord: c'est sur ces rochers en un mot, qui paroissent nues aux spectateurs ordinaires, que se trouve la plus grande vari�t� de ces petites plantes, qui font les d�lices des botanistes, et l'une des sources les plus abondantes o� la m�dicine puise les secours r�els qu'elle fournit � l'humanit�.

�Quelle richesse dans les ressources de la nature! La pesanteur n'est pas plus pr�te � entra�ner les pierres qui se d�tachent des montagnes, que l'air � fournir de semences celles qui se fixent: et d�s qu'une fois elles sont recouvertes de plantes, elles sont certainement fix�es pour toujours, du moins contre les injures de l'air. Le fait m�me nous l'annonce. Si ces ravins ou ces terreins quelconques, tendoient encore � rouler ou � se d�grader, en un mot � se detruire de quelque mani�re que ce fut, ils ne le recouvriroient, ni de mousses ni d'aucune autre plante. La premi�re v�g�tation est due � quelque d�p�t de terre v�g�table; et les pluies ou l'air n'en forment que lentement; le moindre mouvement la d�truite. Le terrein est donc bien certainement fixe quand il se recouvre de plantes; et s'il s'y accumule de la terre v�g�table, c'est un signe bien evident que rien ne l'attaque plus: car elle seroit la premi�re emport�e si quelque cause ext�rieure tendoit a detruire le sol qui la porte.�

The doctrine here laid down by our author consists in this; first, That there is a genus of plants calculated to grow upon rocks or stones; those hard bodies then decay, in decomposing themselves, and affording sustenance to the plants which they sustain. Secondly, That by this dissolution of those rocks, and the accumulation of those vegetable bodies, there is soil prepared for the nurture and propagation of another genus of plants, by which the surface of the earth, naturally barren, is to be fertilised. It is also in this natural progress of things that the solid parts of the globe come to be wasted in the operations of the surface, and that lofty rocks are levelled, in always tending to bring the uneven surface of the earth to a slope of vegetating or fertile soil.

Here we are to distinguish carefully between the facts described by this author, who has seen so much of nature, and the conclusion which he would draw from his principles. The surface of most stones are dissolved, or corroded by the air and moisture. This gives lodgement to the roots of plants, which grow, die, and decay; and these are carried away with the earthy parts of the solid stone, in order to form a vegetable soil for larger plants, growing upon some bottom or resting place to which that earth is carried. Here is so far the purpose of rocks, to sustain a genus of plants which are contrived to live upon that soil; and here is so far a purpose for certain plants, in decomposing rocks to form a soil for other plants which have been made upon a larger scale, and are adapted to the use of man, the ultimate in the view of nature.

Our author concludes thus: (p. 37.) �Le tems ne fera qu'augmenter l'�paisseur de la couche de terre v�g�table qui couvre les montagnes, et qui les garantit ainsi de plus en plus de cette destruction � laquelle on les croit expos�s: les pluies en un mot, au lieu de les d�grader comme on se l'imagine y accumuleront leurs d�p�ts. Tel est l'agent simple qu'employe si admirablement le Createur pour la conservation de son ouvrage.�

Such, indeed, is the admirable contrivance of the system, that, in the works of nature, nothing shall be destroyed more than is necessary for the preservation of the whole. But, that the whole is preserved by the necessary destruction of every individual body, and the change of every part which comes within the examination of our senses, is sufficiently evident to require no farther illustration in this place, where we are contemplating the destruction of the strongest things, by means the most effectual, though really slow, and apparently most feeble.

In his 30th letter, this author describes the progress of nature, in bringing precipitous rocks to that slope and covering of soil which is to maintain plants of every kind, and to establish woods. (P. 40.) �J'ai l'honneur d'exposer � V.M. les causes qui garantissent de destruction ext�rieure les terreins sur lesquels la pesanteur ne peut plus agir que pour les consolider. Mais ce n'est pas ainsi que sont actuellement la plupart de nos montagnes; il en est peu qui soyent d�j� parvenus � cet �tat permanent. Tout roc nud est attaqu� par l'air et les m�t�ores, et il tend � se d�truire quelle que soit sa duret�. Mais ce seroit peu que cette destruction ext�rieure; elle pourroit m�me cesser enfin totalement par l'effet seul des mousses, s'il n'y avoit pas des causes plus puissantes qui pendant quelque tems agissent dans l'int�rieur.

�Il n'est presque point de rocher qui offre � l'air une seule masse compacte; ils sont ou crevass�s, ou form�s par couches; et l'eau s'insinue toujours dans ces fentes. Quand cette eau vient � se geler, elle agit comme un coin pour �carter les pi�ces entre lesquelles elle se trouve. V.M. seroit �tonn�e de la grandeur des masses que cette cause peut mouvoir: elle agit exactement comme la poudre � canon dans les mines; d�tachant toutes les pi�ces ext�rieures qui commencent � se s�parer, et en d�couvrant ainsi de nouvelles. Chaque hiver renouvelle donc la surface de certains rochers, ou facilite l'ouvrage pour les hivers suivans.

Plusieurs autres causes agissent encore pour s�parer les rochers d�j� crevass�s, qui se trouvent � l'ext�rieur des faces escarp�es. Le petit moellon qui s'y accumule, les d�p�ts des pluies, les plantes qui y croissent, les alternatives de l'humidit� et de la s�cheresse, les vicissitudes de la chaleur, les vents m�me, sont autant de causes continuellement agissantes quand la pesanteur les seconde. Les rochers escarp�s se d�truisent donc par de continuels �boulemens.

�Mais toutes ces mati�res qui tombent, ne sont pas perdues pour les montagnes; il s'en perd m�me bien peu. Elles s'arr�tent au pied des rochers dont elles sont successivement d�tach�es; et l� elles s'entassent, s'�levant en forme de talus contre ces rochers eux-m�mes.�

If the solid body of the Alps, the most consolidated masses of our land, is thus reduced to the state of soil upon the surface of the earth contrived for the use of plants, a fortiori, softer bodies, less elevated and less consolidated masses, will be considered as easily arriving at the purpose for which the surface of the earth has been intended. We only wish now to see the ultimate effect that necessarily follows from this progress of things; and how, in this course of nature, the land must end, however long protracted shall be the duration of this body, and however much economy may be perceived in this gradual waste of land;--a waste which by no means is so slow as not to be perceived by men reasoning in science; although scientific men, either reasoning for the purpose of a system which they had devised, or, deceived by the apparent state of things which truly change, may not acknowledge the necessary consequence of what they had perceived.

Let us now suppose all the solid mass of land, contained in our continent, to be transformed into soil and vegetable earth, it must be evident that no covering of plants, or interlacing of vegetable fibres, could protect this mass of loose or incoherent materials from the ravages of floods, so long as rivers flowed, nor from being swallowed by the ocean, so long as there were winds and tides. From the border of the land upon the shore, to the middle of the ocean, there is either at present an equable declivity at the bottom of the sea, or every thing tends to form this declivity, in gradually moving bodies along this bottom. But, however gradual the declivity of the bottom, or however slow the progress of loose materials from the shore towards the deepest bottom of the sea, so long as there are moving powers for those materials, they must have a progress to that end; the law of gravitation, always active, must prevail, and sooner or later the moving sea must swallow up the land.

But, along the borders of our continent, and in the courses of our rivers, there are rocks; these must be surmounted or destroyed, before the parts which they protect can be delivered up to the influence of those moving powers which tend to form a level; and we may be assured that those bulwarks waste. The bare inspection of our rocky coasts and rivers will satisfy the enlightened observator of this truth; and to endeavour to prove this to a person who has not principles by which to reason upon the subject, or to one who has false principles, by which he would create perpetual stability to decaying things, would be but labour lost.

In proportion as the solid bulwark is destroyed, so is the soil which had been protected by it; and, in proportion as the solid parts of the mass of land are exposed to the influences of the atmosphere and water, by the ablution of the soil, more soil is prepared for the growth of plants, and more earth is detached from the solid rock, to form deep soils upon the surface of the earth, and to establish fertile countries at the mouths of rivers, even in making encroachment on the space allotted for the sea. But this production of land, in augmentation of our coasts, is only made by the destruction of the higher country. While, therefore, we allow that there is any augmentation made to the coast, or any earthy matter travelling in our rivers, the land above the coast cannot be stable, nor the constitution of our earth fixed in a state which has no tendency to be removed.

M. de Luc, in his Histoire de la Terre, would make the mountains last for ever, after they have come to a certain slope. He sums up his reasoning upon this subject in these words: �L'adoucissement des pentes arr�te d'abord l'effet de ces deux grandes causes causes de destruction de montagnes, la pesanteur et les eaux: la v�g�tation ensuite arr�t� l'effet de toutes les petites cause.�

If all the great and little causes of demolition are arrested by the slope of mountains and the growth of plants, the surface of the earth might then remain without any farther change; and this would be a fact in opposition to the present theory, which represents the surface of the earth as constantly tending to decay, for the purpose of vegetation, and as being only preserved from a quick destruction by the solid rocks protecting, from the ravages of the floods and sea, the loose materials of the land. It will therefore be proper to show, that this author's argument does not go to prove his proposition in the terms which he has given it, which is, that those sloped mountains are to last for ever, but only that these causes, which he has so well described, make the destruction of the mountains become more slow[9].

[Footnote 9: This also would appear to be a part of that wise system of nature, in which nothing is done in vain, and in which every thing tends to accomplish the end with the greatest marks of economy and benevolence. Had it been otherwise, and the demolishing powers of the land increased, in a growing rate with the diminution of the height, the changes of this earth and renovation of our continent, in which occasionally animal life must suffer, would necessarily require to be often repeated; and, in that case, chaos and confusion would seem to be introduced into that system which at present appears to be established with such order and economy that man suspects not any change; it requires the views of scientific men to perceive that things are not at present such as they were created; it requires all the observation of a natural philosopher to know that in this earth there had been change, although it is not every natural philosopher that observes the benevolence accompanying this constitution of things which must subsist in change.]

The slope which our author gives to his mountains, in order to secure them from the ravages of time, is that which, according to his own reasoning, renders them fertile and proper for the culture of man; but fertile soil yields always something to the floods to carry away; and, while any thing is carried from the soil, the land must waste, although it may not then waste at the rate of those within the valleys of the Alps. According to the doctrine of this author, our mountains of Tweeddale and Tiviotdale, being all covered with vegetation, are arrived at that period in the course of things when they should be permanent. But is it really so? Do they never waste? Look at the rivers in a flood;--if these run clear, this philosopher has reasoned right, and I have lost my argument. Our clearest streams run muddy in a flood. The great causes, therefore, for the degradation of mountains never stop as long as there is water to run; although, as the heights of mountains diminish, the progress of their diminution may be more and more retarded.

Let us now see how far our author has reasoned justly with regard to vegetation, which, he says, stops the effects of all the little causes of destruction; this is the more necessary, as, in the present theory, it is the little causes, long continued, which are considered as bringing about the greatest changes of the earth.

Along the courses of our rivers there are plains between the mountains of greater or lesser extent; these are almost always fertile, and generally cultivated when large; when small, they are in pasture. The origin of these fertile soils, and their perpetual change, is to be described with a view to show, that vegetation, although most powerful in stopping the ravages of water, and for accumulating soil retained by this means, does it only for a time; after which the soil is again abandoned to the ravages of the running water, when no more protected by the vegetation.

Let us suppose the river running upon the one side of the haugh (which is the name we gave those little fertile plains) and close by the side of the mountain. In this case the bed of the river is deepest at the side of the mountain, which it undermines, leaving a falling (un �boulement) on that side; on the other side, the river shelves gradually from the plain, and leaves soil in its bottom or stony bed upon the side of the haugh, in proportion as it makes advances in carrying away the bank at the bottom of the sloping mountain. The part which vegetation takes in this operation is now to be considered.

When the river has enlarged its bed by preying upon one side, whether of the mountain or the haugh, the water only covers it in a flood; at other times, it leaves it dry. Here, among the rocks and stones, the feeds of plants, left by the water or blown by the wind, spring up and grow; and, in little floods, some sand and mud is left among those plants; this encourages the growth of other plants, which more and more retain the fertile spoils of the river in its floods. At last, this bed of the river is covered perfectly with plants, which having retained plenty of fertile soil, although still rooted among the stones, opposes to the river a resistance which its greatest velocity is not able to overcome. In this state, the haugh is always deepening or increasing its soil, and has its surface heightened. At last, when this soil becomes so high as only to be flooded now and then, it becomes most fertile, as the heavier parts are carried in the bed of the river, and the lighter soil deposited upon the plain. The operations of the river, upon the plain, thus increase at the same time the height and fertility of the haugh. But this operation, of accumulated soil upon the stony bottom, has a period, at which time the river must return again upon its steps, and sweep away the haugh which it had formed. This is the natural course of things; and it happens necessarily from the deepening of the soil. Let us then examine this operation.

When no more soil is left upon the stony bottom than is sufficient for the covering of the ground, and rooting of plants which are also fixed in the solid ground or bottom of the soil, the water is not able to carry away the plants; and these plants protect the surface of loose soil. When again there is a depth of soil accumulated upon the haugh, the surface only is protected by the vegetable covering. But what avails it to the soil to be protected from above, when undermined by the enemy! The vegetable roots now no longer reaching to the bottom where solidity is found, the tender soil below is easily washed away by the continued efforts of the stream; and the unsupported meadow, with the impregnable texture of its leaves, its roots, and its fibres, falls ruinously into the river, and is born away in triumph by the flood. The water thus reclaims its long deserted bed,--only in order to pass from it again, and circulate or meander from hill to hill in varying perpetually its course.

Now this progress of the river, or this changing of its bed, is determined by the strong resistance of the new made haugh, humbly standing firm in the protection of its vegetation, while the elevated surface of the older haugh, deserted by the inferior soil which it had ceased to protect, falls a victim to its exalted state, and passes away to aggrandize another. This is the fate of haughs or plains erected by the operations of a river, and again destroyed in the natural course of things, or in the very continuation of that active cause by which they had been formed.

The water is constantly carrying the moveable soil from the higher to the lower place; vegetation often disputes the possession of these spoils of ruined mountains for a while; but, in the end, this vegetable protector, not only delivers up to the destroying cause the mineral soil which it had preserved, but, by its buoyancy in water, it facilitates the transportation of the stony parts to which this fibrous body is attached. Over and over a thousand times may be repeated this alternate possession of the transferable soil, by moving water on the one part and by fixed vegetation on the other, but at last all must land upon the shore, whether the river tends. Thus the mountain and the plain, the vegetable earth and the plants produced in that soil, must all return into the sea from whence either they themselves or their materials had come. In proportion as the mountains are diminished, the haugh or plain between them grows more wide, and also on a lower level; but, while there is a river running in a plain, and floods produced in the seasons of rain, there can be nothing stable in this constitution of things evidently founded upon change.

The description now given is from the rivers of this country, where it is not unfrequent to see relicts of three or four different haughs which had occupied the same spot of ground upon different levels, consequently which had been formed and destroyed at different periods of time. But the same operation is transacted every where; it is seen upon the plains of Indostan, as in the haughs of Scotland; the Ganges operates upon its banks, and is employed in changing its bed continually as well as the Tweed[10]. The great city of Babylon was built upon the haugh of a river. What is become of that city? nothing remains,--even the place, on which it stood, is not known.

[Footnote 10: An Account of the Ganges and Burrampooter Rivers, by James Rennel, Esquire. Philosophical Transactions, 1781.]

The Same Subject continued, in giving a View of the Operations of Air and Water upon the Surface of the Land.

We have but to enlarge our thoughts with regard to things past by attending to what we see at present, and we shall understand many things which to a more contracted view appear to be in nature insulated or without a proper cause; such are those great blocks of granite so foreign to the place on which they stand, and so large as to seem to have been transported by some power unnatural to the place from whence they came. We have but to consider the surface of this earth as having been upon a higher level; as having been every where the beds of rivers, which had moved the matter of strata and fragments of rocks, now no more existing; and as thus disposed upon different planes, which are, like the haughs of rivers, changing in a continual succession, but changing upon a scale too slow to be perceived. M. de Luc has given a picture which is very proper to assist our imagination in contemplating a more ancient state of this earth, although in this he has a very different end in view, and means to show that the world, which we inhabit at present, is of a recent date. It is in the 32d letter of his Histoire de la Terre, which I beg leave here to transcribe.

�Des montagnes basses (comme le Jura, qui est bas comparativement aux Alpes) sont bient�t fix�es par ce moyen. Il ne se fait presque qu'un seul talus depuis leur sommet jusques dans les basses vall�es, ou sur la plaine. Aussi l'�tat de ces montagnes est-il d�j� presqu'enti�rement fix�: on y voit tr�s peu de rochers nuds qui s'�boulent, except�, aupr�s des rivi�res. C'est dans ces lieux-la que l'ouvrage tarde le plus � se finir. Le bas des talus est min� par l'eau; leur surface s'�boule donc, pour ainsi dire, sans cesse, et laisse � d�couvert les rochers des sommets, qui par la continuent aussi � s'�bouler. Mais les vall�es s'�largissent enfin; et les talus s'�loignant ainsi des rivi�res, commencent � �prouver les influences du repos.�

Here nothing can be more positively described than the natural destruction of those mountains by the operation of the rivers which run between them; and this is from the authority of matter of fact, which, on all occasions, this author faithfully describes. At the same time, we are desired to believe, upon no better authority than the imagination of a person hurried on by system, that those mountains are absolutely to come to rest. I am aware of the danger to which a spirit of systematising leads; and I wish for nothing more than to have my Theory strictly examined, in comparing it with nature.

Our author thus proceeds: �La vue seule de la chaine du Jura nous apprend donc ce que deviendroit enfin toutes les montagnes. Dans la plus grande partie de son �tendue, il ne souffre plus aucun changement ruineux: la v�g�tation le recouvre presque partout. Les bas sont cultiv�s de toute sorte de mani�re suivant leur exposition; les sommets sont couverts de pelouses, qui forment les p�turages les plus precieux. Cette gazonade s'�tend aussi sur toutes les parties des pentes qui ne sont pas trop rapides, et le reste est couvert de bois.

�J'ai parcouru fort souvent le pied de ces montagnes: leur �tat est presque partout tel que je viens d'avoir l'honneur de la descrire � V.M. J'ai sur-tout observ� avec attention les lits des torrens qui, en descendent pour se rendre dans les lacs de Geneva, de Neufch�tel et de Bienne, ainsi que dans l'Aar et dans le Rhin: et hormis ceux de ces torrens qui viennent des gorges o� les terrains sont encore escarp�s, ils ne roulent plus que l'ancien gravier qu'ils out apport� autrefois.

�Mais il n'en est pas ainsi des Alpes, des Pyr�n�es, et des autres montagnes, qui, comme celles-l�, sont beaucoup plus �lev�es, ou qui sans l'�tre davantage ont �t� livr�es aux influences de l'air dans un d�sordre plus grand. Dans ce genre de montagnes il reste encore � la v�g�tation de bien grandes conqu�tes � faire.

�Ces montagnes ne sont pas telles que V.M. pourroit se les figurer naturellement; il faut y �tre mont� pour s'en former une juste id�e. Ce sont des montagnes sur d'autres montagnes. De pr�s on ne voit que les parties inf�rieures; de loin tout se confond; il faut donc �tre arriv� sur une des premi�res terrasses pour voir les secondes; sur celles-ci pour les troisi�mes; et ainsi de suite.

�La plupart de ces terrasses successives sont de grandes plaines, domin�es par des rochers qui s'�boulent, et forment des talus. Si dans la succession des si�cles, les �boulemens de ces bandes de rochers en amphith��tre finissoient sans emporter les plaines qu'ils soutiennent, et que les torrens eussent creus� leur lit pendant ce tems l� � quelque distance des talus tout seroit fini par cette premi�re operation. Mais il y a peu de hautes montagnes o� les arrangemens soient si simples: souvent ces bandes empi�tent les unes sur les autres en s'�boulant, et alors le repos est bien diff�r�.

�Supposons que ces terrasses soient �troites, et que leurs murs, c'est-�-dire les rochers qui les soutiennent, soient fort �lev�s. Les terrasses alors ne suffiront pas pour recevoir les �boulemens qui doivent se faire sur elles car le dessus de chacune d'elles s'�tr�cit de plus en plus par la destruction du rocher qui la soutient. Il pourra donc arriver que ce talus, s'�tant �tendu jusqu'au bord de la terrasse, se trouve reposer sur une base qui s'�boule encore; et m�me cela arrive tr�s souvent; de sorte qu'� chaque r�tr�cissement de la base, le talus lui-m�me s'�boule. Ainsi deux talus, qui �toient peut-�tre d�j� en pleine v�g�tation par la lenteur des �boulemens des rochers qui les formoient, pourront �tre fort recul�s � cet �gard; le talus sup�rieur, parce que la surface fertilis�e glissera en bas; et le talus inf�rieur, parce que la sienne sera ensevelie sous de nouveaux d�combres.

�Les montagnes qui sont dans ce cas seront proportionnellement plus abaiss�es que les autres; parce que leurs talus se confondant ainsi et devenant par l� fort �tendus demeureront longtemps � devenir solides. Les eaux partant de fort haut, auront le tems de s'y rassembler et de devenir destructives vers le bas. Au lieu que dans les montagnes o� les terrasses subsisteront encore apr�s que tous les rochers se seront �boul�s, les eaux �tant re�ues par reprises, perdront beaucoup de leur rapidit�. Elles se rassembleront dans les enfoncemens des petites vall�es sup�rieures, elles s'y formeront des lits qu'elles ne rongeront presque point; et la v�g�tation restera tranquille partout.�

Let us now consider the height of the Alps, in general, to have been much greater than it is at present; and this is a supposition of which we have no reason to suspect the fallacy; for, the wasted summits of those mountains attest its truth. There would then have been immense valleys of ice sliding down in all directions towards the lower country, and carrying large blocks of granite to a great distance, where they would be variously deposited, and many of them remain an object of admiration to after ages, conjecturing from whence, or how they came. Such are the great blocks of granite which now repose upon the hills of Saleve. M. de Saussure, who has examined them carefully, gives demonstration of the long time during which they have remained in their present place. The lime-stone bottom around being dissolved by the rain, while that which serves as the basis of those masses stands high above the rest of the rock, in having been protected from the rain. But no natural operation of the globe can explain the transportation of those bodies of stone, except the changed state of things arising from the degradation of the mountains.

Every thing, therefore, tends to show that the surface of the earth must wear; but M. de Luc, although he allows the principles on which this reasoning is founded, labours to prove that those destructive causes will not operate in time. Now, What would be the consequence of such a system?--That the source of vegetation upon the surface of the earth would cease at last, and perfect sterility be necessarily the effect of allowing no farther degradation to the surface of the earth; for, What is to supply the matter of plants? Water, air, and light alone, will not suffice; there are necessarily required other elements which the earth alone affords. If, therefore, this world is to continue, as it has done, to form continents of calcareous strata at the bottom of the ocean, the animals which form these strata, with their exuviae, must be fed. But, on what can they be fed? not on water alone; the consequence of such a supposition would lead us to absurdity; nor can they be fed on any other element without the dissolution of land. According to my views of things, it is certain that those animals are ultimately fed on vegetable bodies; and it is equally certain, that plants require a soil on which they may not only fix their fibrous roots, but find their nourishment at least in part; for, that air, water, and the matter of light, also contribute, cannot be doubted. But if animals, which are to form the strata of the earth, are to be fed on plants, and these are to be nourished by the matter of this earth, the waste of vegetable matter upon the surface of the earth must be repaired; the exhausted soil must be transported from the surface of the land; and fertility must be restored by the gradual decay of solid parts, and by the successive removal of soil from stage to stage. What a reverie, therefore, is that idea, of bringing the earth to perfection by fixing the state of its vegetable surface!

The description of those natural operations, which M. de Luc has given with a view to establish the duration of the mountains, is founded upon nothing but their destruction. These beds of rivers, which, according to our author, are hardly to be wasted any more, will not satisfy a philosopher, who requires to see no degree of wasting in a body which is to remain for ever, or continue without change. But, however untenable this supposition of a fixed state in the surface of this earth, the accuracy of the natural philosopher may still be observed in the absurdity of the proposition. �L'�tat des montagnes sera fixe, partout o� les rivi�res seront arriv�es au point de n'emporter pas plus de limon hors de leur enceinte, que l'air et les pluies n'y d�poseront de terre v�g�table, et voila enfin quel sera le repos, l'�tat permanent de la surface de notre globe. Car alors il y aura compensation entre les destructions et les r�parations simultan�es, et les montagnes s�rement ne s'abaisseront plus.�

Surely, if there is in the system of nature wisdom, we may look for compensation between the destroying and repairing operations of the globe. But why seek for this compensation in the rest or immobility of things? Why suppose perfection in the want of change? The summit of the Alps was once the bottom of the sea; the existence of our land depended then upon the change of seas and continents. But has the earth already undergone so great changes, and is it not yet arrived at the period of its perfection? How can a philosopher, who is so much employed in contemplating the beauty of nature, the wisdom and goodness of Providence, allow himself to entertain such mean ideas of the system as to suppose, that, in the indefinite succession of time past, there has not been perfection in the works of nature? Every material being exists in motion, every immaterial being in action and in passion; rest exists not any where; nor is it found in any other way, except among the parts of space. Surely it is contrary to every species of philosophy, whether ancient or modern, to found a system on the inutility of repose, or place perfection in the vacuity of rest, when every thing that truly exists, exists in motion; when every real information which we have is derived from a change; and when every excess in nature is compensated, not by rest, but by alternation.

M. de Luc allows the rivers to carry matter always to the sea; but then, at a certain period, this matter carried by the floods is to be compensated to the mountains by the vegetable earth received from the air and rains. Here is a proposition which should be well considered, before it be admitted as a principle, which shall establish the perpetuity of these mountains, if it be true; or, if false, assure us of their future demolition. Let us now examine it.

If from air and rain there is produced earth which cannot afterwards be resolved by the operation of those elements, and thus again dissolved in the air and water of the land, then this author might have had some pretext, however insufficient, for alledging that it might be possible to compensate the loss of mineral substances, carried off the surface of the earth, by the production of this vegetable matter from the air and rain; but, when there is not sufficient reason to conclude that any substance, produced in vegetation, can resist the continued influences of the air and water, without being decomposed in its principles, and at last entirely dissolved in water, the cautious argument here employed by this author, for the permanency of mountains, must appear as groundless in its principle as it would be insufficient for his purpose, were it to be admitted; but this will require some discussion.

That which preserves vegetable bodies so long from dissolution in water, is what may be called the inflammable or phlogistic composition of those bodies. This composition is quickly resolved in combustion; but it is no less surely resolved by the influences of the sun and atmosphere, only in a slower manner. Therefore, to place the permanency of this earth, or any of its surface, upon a substance which in that situation necessarily decays, is to form a speculation inconsistent with the principles of natural philosophy[11].

[Footnote 11: It is from inadvertency to this fact in natural history, the consuming of vegetable substances exposed to the influences of the atmosphere, that M. de Luc, in his Histoire de la Terre, has pretended to determine the past duration of the German heaths as not of a very high antiquity. He has measured the increase of the vegetable soil, an increase formed by the accumulation of the decayed heath; and, from the annual increase or deposits of vegetable matter on that surface, he has formed a calculation which he then applies to every period of this turfy augmentation, not considering that there may be definitive causes which increase with this growing soil, and which, increasing at a greater rate in proportion as the soil augments, may set a period to the further augmentation of that vegetable soil. Such is fire in the burning of those parched heaths; such is the slower but constant and growing operation of the oxygenating atmosphere upon this turfy substance exposed to the air and moisture. This author has very well described the constant augmentation of this vegetable substance in the morasses of that country, as it also happens in those of our own; but there is a wide difference in those two cases of peat bog and healthy turf; the vegetable substance in the morass is under water, and therefore has its inflammable quality or combustible substance protected from the consuming operation of the vital or atmospheric air; the turfy soil, on the contrary, is exposed to this source of resolution in the other situation.]

But even supposing that the degradation of mountains were to be suspended by the pretended compensation which is formed, by the rivers carrying mineral mud into the sea, and the air and rain producing vegetable earth; in what must this operation end? In carrying into the sea, to be deposited at its bottom, all the vegetable earth produced by the air and rain. But our cosmologist, in thus procuring an eternal station to his mountains, has not told us whether this transmutation of the air and rain be a finite operation, or one that is infinite; whether it be in other respects confident with the natural operations of the globe; and whether, to have the air and water of the globe converted into earth, would ultimately promote, or not, that perfection which he wishes to establish. Here, therefore, in allowing to this philosophy all its suppositions, it would be necessary to make another compensation, in preserving mountains at the expense of air and rain; and, the waste of air and water, which are limited, would require to be repaired.

It is not in our purpose here to treat of moral causes; but this author having endeavoured to fortify his system by observing, that the world certainly cannot be ancient, since men have not ceased as yet to quarrel and fight, (Lettre 34.) it may be proper to observe, that the absolute rest of land, like the peace among mankind, will never happen till those things are changed in their nature and constitution, that is to say, until the matter of this globe shall be no more a living world, and man no more an animal that reasons from his proper knowledge, which is still imperfect. If man must learn to reason, as children learn to speak, he must reason erroneously before he reasons right; therefore, philosophers will differ in their opinions as long as there is any thing for man to learn. But this is right; for, how are false opinions to be corrected, except in being opposed by the opinions of other men? It is foolish, indeed, for men to quarrel and fight, because they differ in opinion. Man quarrels properly, when he is angry; and anger perhaps is almost always ultimately founded upon erroneous opinion. But, in nature, there is no opinion; there is truth in every thing that is in nature; and in man alone is error. Let us, therefore, in studying nature, learn to know the truth, and not indulge erroneous notions, by endeavouring to correct, in nature, that which perhaps is only wrong in our opinion.

Having shown that every thing, which is moveable upon the surface of the land, tends to the sea, however slowly in its pace, we are now to examine, what comes of those materials deposited within the regions of the waves, still however within the reach of man, and still subservient more immediately to that soil on which plants grow, and man may dwell.

As, from the summit of the land, the natural tendency of moveable bodies is to fall into the water of the sea, so, from the borders of the land or coast, there being a declivity towards the deepest bottom of the sea, and there being currents in the waters of the ocean occasionally rendered more rapid on the shore, every moveable thing must tend to travel from the coast, and to proceed alone; the shelving bottom of the sea into the unfathomable deep, when they are beyond the reach of man or the possibility of returning to the shore.

But it is not every where upon the coast that those materials are equally delivered; neither is it every where along the shore that the currents of the ocean are equally perceived, or operate with equal power in moving bodies along the shelving bottom of the sea. Hence in some places deep water is found washing rocky coasts, where the waste of land is only to be perceived from what is visibly wanting in the continuity of those hard and solid bodies. In other places, again, the land appears to grow and to encroach upon the space which had been occupied by the sea; for here the materials of the land are so accumulated on the coast, that the bottom of the sea is filled up, and dry land is formed in the bafon of the sea, from those materials which the rivers had brought down upon the shore.[12]

[Footnote 12: We are not however to estimate this operation, of forming soil by the muddy waters of a river depositing sediment, in the manner that M. de Luc has endeavoured to calculate the short time elapsed in forming the marshlands of the Elbe. This philosopher, with a view to show that the present earth has not subsisted long since the time it had appeared above the surface of the sea, has given an example of the marsh of Wisebhafen where the earth, wasted by inundation, was in a very little time replaced, and the soil heightened by the flowings of the Elbe, and this he marks as a leading fact or principle, in calculating the past duration of our continents, of which he says, we are not to lose sight (Tome 5, p. 136.) But here this philosopher does not seem to be aware, that he is calculating upon very false grounds, when he compares two things which are by no means alike, the natural operations of a river upon its banks, making and unmaking occasionally its haughs or level lands, that is to say, alternately making and destroying, and the artificial operations of man receiving the muddy water of a tide-way into the still water of a pond formed by his ramparts; yet, it is by this last operation that our author forms an estimate which he applies to the age of this earth, in calculating how long time might have been required for producing the marsh lands of the Elbe.

I would here ask if he can calculate what time it may have required to hollow out the bed of the Elbe from its source to the sea; and to tell how often the marsh-lands, which he now sees cultivated, had been formed and destroyed by the river before they were cultivated in their present state; or if there is any security that they shall not again be taken away by the river, and again formed in the same place. If this is the case, that the river is constantly changing the fertile lands, which it forms by its inundation, what judgement are we to form by calculating the quantity of sediment in a certain measure of its muddy water.]

Holland affords the very best example of this fact. It is a low country formed in the sea. This low land is situated in the bottom of a deep bay, or upon the coast of a shallow sea, where more materials are brought by the great rivers from the land of Germany than what the currents of the sea can carry out into the deep. Here banks of sand are gathered together by streams and tides; this sand is blown in hillocks by the wind; and those sand hills are retained by the plants which have taken root and fixed those moving sands. Behind that chain of hillocks, which line the sea shore, the waters of the rivers formed a lake, and the bottom of this lake had been gradually filled up or heightened by materials travelling in the rivers, and here finding rest. It grew up until it became a marsh; then man took possession of the soil; he has turned it to his own life; and, by artificial ramparts of his forming, preserves it in the present state, some parts above the level of the sea, others considerably below the ordinary rise of tides. M de Luc, who has given a very scientific view of this country in his Lettres Physiques et Morales, has there also furnished us with the following register of what had been found by sinking in that soil. It was at Amsterdam at the year 1605 in making a well.

�Voici la d�signation des mati�res qui furent trouv�es en partant de la surface.

51 pieds, m�l�s de sable tourbeux, de fable des dunes pur et d'argile ou limon.

22.---de m�me sable des dunes pur, et d'argile bleu�tre.

14.---du m�me sable pur.

87 pieds.--Ou rien encore n'indiquoit la pr�sence de la mer.

55.---de sable marin, et de limon, m�les l'un et l'autre de coquilles dans plusieurs couches.

142 pieds.--Soit la plus grande profondeur, o� s'est manifest�e la pr�sence de la mer.

49.---Argille dure sans m�lange de coquilles, soit que ce soit une couche argilleuse continentale, ou les premiers d�p�ts des fleuves; ce qu'il est difficile de D�terminer.

191 pieds.

13.---Sable m�l� de pierres; qui est enfin s�rement le sol vierge continental.

28.---Sable pur; continental encore; car j'ai remarqu� partout dans la Geest, que c'est dans la couche sup�rieure, � une petite profondeur que se trouvent les pierres; au-dessous le sable est pur.

232 pieds.--C'est � cette profondeur, ou dans la masse de ces deux derni�res couches, que se trouva l'eau douce, et par cons�quent le vrai sol continental.�

The light that we have from this pit which has been made in the soil, according to my view of the subject, is this, that here is the depth of 232 feet in travelled soil, and no solid bottom found at this distance from the surface or level of the sea. How far this depth may be from the bottom of these travelled materials is unknown; but this is certain, that all that depth, which has been sunk, had been filled up with those materials[13].

[Footnote 13: An interesting map for the use of natural history would be made by tracing the places (behind this country of loose or travelled soil) where the solid strata appear above the level of the sea. We should be thus able to form some notion of the quantity of materials which had been deposited in the water of this sea. But, though we might thus enlarge our views a little with regard to the transactions of time past, it would only be in a most imperfect manner that we would thus form a judgment; for, not knowing the quantity of sand and mud carried out by the currents from the German sea into the Atlantic, we could only thus perceive a certain minimum, which is perhaps a little portion of the whole.]

It will thus appear of what unstable materials is composed the land of that temporary country. It will also be evident, that, by removing the sand banks of this coast, the whole of this low country would be swallowed by the sea, notwithstanding every effort that the power of man could make. But it may be alledged, that those sand banks are increasing still with the alluvion of Germany, instead of being in a decreasing state. I should also incline to believe that this is truly the case; but, though we may acknowledge the growth of land upon the coast of Holland, we must deny that a stable country can be formed in the bed of the sea by such means. For, however increasing may be the sand in the German sea, and however great additions may be made of habitable country to the coast of Holland, yet, as the islands of Great Britain and Ireland are worn by attrition on the shores, and are wasted by being washed away into the ocean, the causes for the accumulation of sand in the German sea must cease in time, when, in this progress of things, the sand banks, on which depends the existence of Holland, must diminish, and at last be swept away, in leaving the solid coast of Germany to be again buffeted by the waves, as is at present the coasts of Ireland, France, and Spain.

This reasoning is, indeed, very far removed from that which is commonly employed for the purpose of conducting human operations, or establishing the political system of a nation; it is not, however, the less interesting to man, in that it cannot direct him immediately in his worldly affairs; and it is the only way of reasoning that can be employed in order to enlighten man with a view of those operations which are not to be limited in time, and which are to be concluded as in the system of nature, a system which man contemplates with much pleasure, and studies with much profit.

Thus we have shown, that, from the top of the mountain to the shore of the sea, which are the two extremities of our land, every thing is in a state of change; the rock and solid strath dissolving, breaking, and decomposing, for the purpose of becoming soil; the soil travelling along the surface of the earth, in its way to the shore; and the shore wearing and wasting by the agitation of the sea, an agitation which is essential to the purposes of a living world. Without those operations, which wear and waste the coast, there would not be wind and rain; and, without those operations which wear and waste the solid land, the surface of the earth would become sterile. But showers of rain and fertile soil are necessarily required in the system of this world; consequently, the dissolution of the rocks, and solid strata of the earth, and the gradual, flow, but sure destruction of the present land, are operations necessary in the system of this world; so far from being evils, they are wisely calculated, in the system of nature, for the general good.

It is not to common observation that it belongs to see the effects of time, and the operation of physical causes, in what is to be perceived upon the surface of this earth; the shepherd thinks the mountain, on which he feeds his flock, to have been always there, or since the beginning of things; the inhabitant of the valley cultivates the soil as his father had done, and thinks that this soil is coeval with the valley or the mountain. But the man of scientific observation, who looks into the chain of physical events connected with the present state of things, sees great changes that have been made, and foresees a different state that must follow in time, from the continued operation of that which actually is in nature.

It is thus that enlightened natural history affords to philosophy principles, from whence the most important conclusions may be drawn. It is thus that a system may be perceived in that which, to common observation, seems to be nothing but the disorderly accident of things; a system in which wisdom and benevolence conduct the endless order of a changing world. What a comfort to man, for whom that system was contrived, as the only living being on this earth who can perceive it; what a comfort, I say, to think that the Author of our existence has given such evident marks of his good-will towards man, in this progressive state of his understanding! What greater security can be desired for the continuance of our intellectual existence,--an existence which rises infinitely above that of the mere animal, conducted by reason for the purposes of life alone.

The view of this interesting subject, which I had given in the first part, published in the Transactions of the Edinburgh Royal Society, has been seen by some men of science in a light which does not allow them, it would appear, to admit of the general principle which I would thereby endeavour to establish. Some contend that the rivers do not travel the material of the decaying land;--Why?--because they have not seen all those materials moved. Others alledge, that stones and rocks may be formed upon the surface of the earth, instead of being there all in a state of decay. These are matters of fact which it is in the power of men who have proper observation to determine; it is my business to generalise those facts and observations, and to bring them in confirmation of a theory which is necessarily founded upon the decaying nature and perishing state of all that appears to us above the surface of the sea.

Nothing is more evident, than that the general effect of mineral operations is to consolidate that which had been in an incoherent state when formed at the bottom of the sea, and thus to produce those rocks and indurated bodies which constitute the basis of our vegetable soil; but, that indurating or consolidating operation is not the immediate object of our observation; and, to see the evidence of that operation, or the nature of that cause, requires a long chain of reasoning from the most extensive physical principles. Our present subject of investigation requires no such abstract distant media, by which the effect is to be connected with its cause; the actual operation in general is the object of our immediate observation; and here we have only to reason from less to more, and not to homologate things which may, to men of narrow principles, appear to be of different kinds. But even here we find difficulty in persuading those who have taken unjust views of things; for, those who will not deny the truth of every step in this chain of reasoning, will deny the end to which it leads, merely because they are not disposed to admit the progress of that order which appears in nature.

In the last chapter, I have been using arguments to prove that M. de Luc has reasoned erroneously, in concluding the future stability of a continent; and I have been endeavouring to show that our continent is necessarily wasted in procuring food to plants, or in serving the various purposes of a system of living animals. We have now in view to illustrate this theory of the degradation of the surface of the earth; a theory necessarily leading to that system of the world in which a provision is made for future continents; and a theory explaining various natural appearances which otherwise are not to be understood. A door may thus be opened for the investigation of natural history, particularly that which traces back, from the present state of things, those operations of nature which are more immediately connected with what we take much pleasure to behold, viz. the surface of the earth stored with such a variety of beautiful plants, and inhabited by such a diversity of animals, all subservient to the use of man.

There are two ways in which we may look for the transactions of time past, in the present state of things, upon the surface of this earth, and read the operations of an ancient date in those which are daily transacted under our eye. The one of these is to examine the soil, and to trace the origin of that which we find loose upon the surface of the earth, or only compacted by the soft and cohesive nature of some of its materials. In thus studying the soil we shall learn the destruction of the solid parts; and though, by this means, we cannot form an estimate of the quantity of this destruction which had been made, we shall, upon many occasions, see a certain minimum of this quantity which may perhaps astonish us.

The second method here proposed, is to examine the solid part of the earth, in order to learn the quantity of matter which had been separated from this mass. Here also we shall not be able to compute the quantity of what had been destroyed; but we shall every where find a certain minimum of this quantity, which will give us an extensive view with regard to the operation of the elements and seasons upon the surface of this earth. We shall now examine more particularly those two ways of judging with regard to the operations of time past, and the changes which have been made upon the surface of our land, by those active causes, which, being in the constitution of this earth, must continue to operate with undiminished power, and tend to preserve the whole amidst the destruction of its particular parts.

The quality of the soil or travelled earth of the globe is various; because the solid parts, from the destruction of which the soil is formed, consist of very different substances, in the different portions of each country. Thus, in one part of a country, the soil will be calcareous, or containing much of that species of substance; in another, again, it will be argillaceous; in another sandy, where the prevailing substance is siliceous. These are the original soils; other substances may be considered as adventitious to this soil, though natural to the surface of the earth, which is covered with plants and animals. The substance of those animal and vegetable bodies, mixed with the soil, adds greater fertility to the earth, and gives a soil which is still more compounded in its nature, but still composed of those materials now enumerated.

We have been now supposing the solid parts below, or in the same field, as furnishing materials of which the soil is formed; this soil then partakes of the nature of those solid parts, whether more simple or more compound. There is, however, another subject of variety, or still greater composition in soils; this is the transportation of materials from a distance; and this, in general, is performed by the ablution of water, in following the declivity of the surface. But sand is sometimes travelled by the wind, and proceeds along the surface of the earth, without regard to the declivity, and changes the nature of soil in those places which happen to be exposed to this accident.

There cannot be any extensive, great, or distant travelling of sand or soil by means of the wind, except in those places which are sterile for want of rain, and thus are destitute of rivers and of streams; for, these running waters form every where a bar to this progressive movement of the soil, even if the sterility or dryness should permit the blowing of the sand. But the operation of streams and rivers, carrying soil and stones along the surface of the earth, is constant, great, and general over all the globe, so far as a superfluity of water, in the seasons of rain, falls upon the earth.

From the amazing quantity of those far travelled materials, which in many places are found upon the surface of the ground, we may with certainty conclude, that there has been a great consumption of the most hard and solid parts of the land; and therefore that there must necessarily have been a still much greater destruction of the more soft and tender substances, and the more light and subtile parts which, during those operations of water, had been floated away into the sea. This appears from the enormous quantities of stones and gravel which have been transported at distances that seem incredible, and deposited at heights above the present rivers, which renders the conveyance of those bodies altogether inconceivable by any natural operation, or impossible from the present shape of the surface. This therefore leads us to conclude, that the surface of the earth must have been greatly changed since the time of those deposits of certain foreign materials of the soil. Examples of this kind have been already given. I shall now give one from the Journal de Physique.

�Les bords du Rh�ne aux environs de Lyon, et sur la longueur de quarante lieues, et de plus, des montagnes enti�res, dans le m�me pays, sont formes de pierres dont on ne trouve les analogues que dans la Suisse. Ce fait presqu'incompr�hensible est accompagn� de beaucoup de circonstances qui m�ritent d'�tre d�taill�es dans un discours plus longue que celui-ci. Il y a cependant une que je ne peux pas m'emp�cher de rapporter ici, comme une suite de ce que je viens de dire.

�Dans cette grand catastrophe, � laquelle j'attribue le transport de ces mati�res alpines, il se fit de grandes �chancrures dans le Jura; les plus profondes que j'aie vues sont celles de Jougue de Sainte-Croix, du val de Mousthier Travers, de Someboz au val de Saint-Inver, une cinqui�me aux environs du village de Grange, trois lieues plus bas que Bienne, et une sixi�me � quatre � cinq lieues plus bas que Soleure, � l'endroit dit la cluse. Cette derni�re est la plus profonde, et se trouve de niveau avec les eaux de l'Aar. Beaucoup de ces mati�res �trang�res au Jura, ont pass� par ces �chancrures, et sans doute, par bien d'autres et se sont r�pandues, dans plusieurs de ces vall�es. J'en ai vu un suite bien marqu�e qui a pass� par Jougue, par Saint-Antoine, part Mont Perreux, les Grangettes, les Granges Friards, Oye, et qui est all�e jusqu'aux plaines de Pontarlier. Cette suite est en ligne droite vis-� vis l'�chancrure de Jougue, et la direction de la vall�e qui est au bas de ce village. On en trouve quelques morceaux � Metabiefs, mais je n'en ai point vu aux Longevilles, ni � Roche-Jean. Il y en a au-dessus de Saint-Croix ou d'autres ont pu passer aussi pour aller de m�me aux environs de Portarlier. Il y en a dans le val de Mousthier-Travers jusqu'au dessus de village de Butte; elles ont m�me pass� les roches de Saint-Sulpice du c�t� des Verri�res de Suisse, ou l'on a �t� oblig� d'en faire sauter de gros blocs avec de la poudre pour d�gager la grande route; il y en a dans les vall�es de Tavannes, et de Delemont; on en trouve bien plus loin, j'en ai vu pr�s de Roulans, et je ne douterois pas que les pierres meuli�res de Moissez et des environs n'eussent la m�me origine.�

M. de Saussure, who has so well observed every thing that can be perceived upon the surface of the earth, gives us the following remarks which are general to mountainous countries. (Voyages dans les Alpes, tome 2d � 717).

�Dans le haut des vall�es entour�es de hautes montagnes, on ne voit point de cailloux roul�es, qui soient �trangers � la vall�e m�me dans laquelle on les trouve; ceux que l'on y rencontre ne sont jamais que les d�bris des montagnes voisines. Dans le plaines au contraire, et � l'embouchure des vall�es, qui aboutissent aux plaines et m�me assez haut sur les pentes des montagnes qui bordent ces plaines, on trouve des cailloux et des blocs que l'on diroit tomb�s du ciel, tant leur nature diff�re de toute ce que l'on voit dans les environs.�

Here are facts which can only be explained in supposing that the valleys have been hollowed out of the solid mass, by the gradual operation of the rivers. In that case stones, travelled from a far, will be found at considerable heights, upon the sides of the valleys at their under end, or where, as our author says, they terminate in plains.

We have a striking example of the operation of time and the influences of the atmosphere, in wasting the surface of the rocks, and forming soil upon the earth; this is the kaolin of the Chinese, or the true porcelain earth, which is the produce of granite countries. The feldspar of the granite rock exposed to the atmosphere is corroded very slowly indeed, by the effects of air and moisture, and in having the soluble earth or calcareous part of its composition dissolved; the surface of this stone, thus, in a long course of time, becomes opaque in having the white siliceous earth exposed to view, and thus appears like a calcined substance. The snows and rain detaches from this surface of the rock the white earth, which being deposited in the plain below, forms a stratum of kaolin more or less pure, according to the circumstance of the place.

As this operation of the atmosphere upon the surface of granite is so extremely slow as to be altogether unmeasurable to man; and as there are in many places of the earth inexhaustible quantities of this kaolin, notwithstanding a small portion only of the ablution of the rock had been retained upon the surface and deposited by itself, it must appear that much time had been required for amassing those beds of kaolin, and that these operations, which in the age of a continent is nothing, or only as a day, are, with regard to the experience of man, unmeasurable.

For approbation of this theory, it is not necessary to show, that wherever there is granite found, there should be also kaolin observed; but it is necessary that wherever kaolin is found, there should be also granite or feldspar to explain its origin; and to this proof the theory is most willingly submitted. The following are the places which have come to my knowledge. First Loch Dune in the shire of Ayr; this lake receives its water from the granite hills which are at its head. Secondly, some small lakes which receive the washings of the granite mountain, Crifle, in East Galloway. Thirdly, Cornwall, a county in which I have not been, but which is sufficiently known as possessing kaolin and granite.

Another example from a very distant country we have both from M. Pallas, in the Oural mountains, and from M. Patrin, who has given a mineralogical notice of the Douari, Journal de physique, Mars 1791. Here we find the following observation.

�Parmi les chose int�ressantes qu'offrent les rives de Chilea, on remarque au dessous de la fonderie, des collines de petunt-f� blanc comme la neige, parsem� de mica argentin de la plus grande t�nuit�. Dans le voisinage de ce petunt-f� est une argile micac�e, qui en est peut-�tre une d�composition: on essaya en ma pr�sence d'en faire de la poterie qui avoit tous les caract�res du meilleurs biscuit de porcelaine.�

We have now been endeavouring to illustrate the wasting and washing away of the solid land, in the examples of decayed rocks and water worn stones, all of which are traceable, though at a great distance, to their source; we are now to consider another species of substance, which is still more particular as to the place of its production, or to its original situation, this being only in the veins of the earth. Among all the various productions of mineral veins, we have only now in view some particular metallic substances which do not seem to waste and be dissolved, as many of them are, in being long exposed to the influence of air and rain. When, therefore, the solid parts of the land are wasted in time, and carried away from the surface of the earth, the contents of the veins, which are occasionally found in those decayed parts of the land, are also carried away in the stream; but as the specific gravity of those metallic contents is much greater than the other stony materials moved in the stream, they sink to the bottom, and tend much more to be deposited upon the land, than those stones which had moved with them from their place. Hence it is, that deposits, rich in those metallic substances, are formed in certain places of the soil; and these are sought for, upon account of the value of their contents. Thus, stream tin, which in the time of the Romans formed a subject of traffic, is still found in the soil of Cornwall, even in great profusion, at this day.

Nothing can tend more to illustrate this travelling of the wasted surface of the solid land, than the contents of those mineral veins suffering in the general destruction of things, but partly saved from that total ablution by which so much of the solid parts had been made to disappear; and nothing can, in a more beautiful manner, show this order of things, than the method practised by the Cornish miners in quest of the original country of that metal, by shoding, (as it is called) upwards in running back the tract in which the stream tin had been conveyed. This is done by trying parcels of the soil, in always mounting to see from whence the mineral below had come.

Gold is thus found almost in every country but it is only in the most sparing manner that it may thus be in general procured, by reason of the few veins in which gold is found, and the small quantity of this metal contained in those veins. America, however, affords an example of veins rich in gold, and it is also there that quantities of stream gold is found in the soil, bearing a due proportion to the number and riches of the veins.

I shall give an example concerning the situation in which this stream gold is found in Peru (Voyage au P�rou, par M. Bouguer, page 49.)

�Cette Cordeli�re occidentale contient beaucoup d'or de m�me que le pied de l'orient, et celui d'une autres cha�ne tr�s-longue qui s'en d�tache un peu au sud de Popayan, et qui apr�s avoir pass� par Santa F� de Bogota, et par M�rida, va se terminer vers Caracas sur la mer du nord; outre que l'or en paillettes occupe toujours des postes assez bas � l'�gard du reste de la Cordeli�re, on ne peut aussi jamais le d�couvrir qu'en enlevant presque toujours deux couches de diff�rentes terres qui le cachent. La premi�re, qui est de la terre ordinaire, a trois ou quatre pieds d'�paisseur et quelquefois dix ou douze. On trouve souvent au dessous une couche moins �paisse qui tire sur le jaune, et plus bas est une troisi�me qui a une couleur violette, qui a souvent trois ou quatre pieds d'�paisseur, mais qui n'a aussi quelquefois qu'un pouce, et c'est cette troisi�me dans laquelle l'or est m�l�. Au dessous la terre change encore de couleur, elle devient noire comme � la surface du sol, et elle ne contient aucun m�tal. D'ailleurs on ne creuse pas indistinctement par tout. On se d�termine � chercher en certains endroits plut�t qu'en d'autres par la pente de terrain. On agit comme si l'or avant que d'avoir �t� couvert par les deux couches sup�rieures, avoit �t� charri� par des eaux courantes. On s'est assur� aussi que les terres une fois lav�es ou d�pouill�e de leurs richesses n'en produisent point d'autres; ce qui prouve que l'or y avoit �t� comme d�pos�.�

Therefore, whether we consider the quantity or the quality of the materials which are found composing the soil upon the surface of the earth, we must be led to acknowledge an immense waste of the solid parts, in procuring those relicts which indicate what had been destroyed.

We have now to examine what is left of that solid part which had furnished the materials of our soil; this is the part which supports the vegetable or travelled earth, and this earth sustains the plants and animals which live upon the globe. It is by this solid part that we are to judge concerning the operations of time past; of those destructive operations by which so great a portion of the earth had been wasted and carried away, and is now sunk at the bottom of the sea.

Man first sees things upon the surface of the earth no otherwise than the brute, who is made to act according to the mere impulse of his sense and reason, without inquiring into what had been the former state of things, or what will be the future. But man does not continue in that state of ignorance or insensibility to truth; and there are few of those who have the opportunity of enlightening their minds with intellectual knowledge, that do not wish at some time or another to be informed of what concerns the whole, and to look into the transactions of time past, as well as to form some judgment with regard to future events.

It is only from the examination of the present state of things that judgments may be formed, in just reasoning, concerning what had been transacted in a former period of time; and it is only by seeing what had been the regular course of things, that any knowledge can be formed of what is afterwards to happen; but, having observed with accuracy the matter of fact, and having thus reasoned as we ought, without supposition or misinformation, the result will be no more precarious than any other subject of human understanding. To those who thus exercise their minds, the following remarks may furnish a subject for some speculation. Now, though to human policy it imports not any thing, perhaps, to know what alterations time had made upon the form and quantity of this earth, divided into kingdoms, states, or empires, or what may become of this continent long after every kingdom now subsisting is forgotten, it much concerns the present happiness of man to know himself, to see the wisdom of that system which we ascribe to nature, and to understand the beauty and utility of those objects which he sees.

There are two different operations belonging to the surface of this globe which we are now to consider, and by which we shall be enabled to form some computation of what had been in space and time, from that which now appears. Moving water is the means employed in both those operations; but, in the one case, it is the water of the sea; in the other again, it is the water of the land. The effect of the one operation is the wasting of the coast, and the diminution of that basis on which our land and soil depends; of the other, again, it is the degradation of our mountains, and the wasting of our soil. In the course of this last operation, there is also occasionally land formed in the sea, in addition to our coast.

With regard to the wearing of the coast by the agitation of the waves, this is an operation of which some understanding is to be formed from the surest of all records, from a careful examination of our shores which are in this decaying state, and by observing what has been removed from those portions which we find remaining. Few people have either the skill or the opportunity of thus judging of the state of our earth from that which actually appears; but there is no person, who studies this science of geology, that may not satisfy himself with regard to the truth of this theory, by looking into our maps and charts, and making proper allowances for causes which cannot appear in the maps, but which may be understood by a person of knowledge making observations on the spot. In order to assist this study, the following observations may be made.

It is a general observation among mariners, that a high coast and rocky shore have deep water; whereas a low coast, and sandy shore, are as naturally attended with shallow water. The explanation of this fact will appear by considering, that a steep rocky coast is occasioned by the sea having worn away the land; and, when that is the case, we are not to expect sand should be accumulated upon that shore, so as to make the sea shallow. Look round all the coasts of Great Britain and Ireland that are exposed to the wide ocean, as likewise those of France and Norway, deep water, and a worn coast, are universally to be acknowledged. If again the coast is shallow, this is a proof that the land affords more materials than the sea can carry away; consequently, instead of being impaired, the coast may here increase and be protruded from the land. Such is the case in many places along the coast of North America, where several reasons concur in accumulating sand upon that coast; for, not only is the shore plentifully provided with sand from the rivers of that continent, but also the sand of the Mexican Gulf would appear to be carried along this coast with the stream which flows here towards the north, and which has thus contributed to form the banks of Newfoundland.

The second general observation is to be considered as respecting the shape of coasts, in like manner as the first had in view their elevations. Now, it is plain that the shape of the coast, in any part of the land, must depend upon a combination of two different causes. The first of these is the composition of the land or solid parts of the coast; if this be uniform and regular, so will be the shape of the coast; if it is irregular and mixed, consisting of parts of very different degrees of hardness and resistance to the wasting operations, the coast will then be, cet. par. irregular and indented. The second, again, respects the wearing power. If this wearing power shall be supposed to be equally applied to all the coast; and, if every part of that coast were of an equal quality or resisting power, no explanation could be given, from the present state of things, for the particular shape of that coast, which ought then to be wasted in an equable manner by the sea. But neither is the coast, of any extensive country at least, composed of such uniform materials; nor is the application of the wearing power to the coast an equal thing; and this will form the subject of another observation. The third general observation, therefore, regards the operations of the sea upon the coast, and the effects which may be perceived in consequence of that cause, independent of the qualities of the coast, or supposing them in general to be alike. Here, according to the theory, we should expect to find deep water and an indented coast upon a country, in proportion as that coast is exposed to the violence of the sea, or is open directly to the ocean. We have but to look along the west coast of Norway, the north-west of Scotland, the west of Ireland, and the south-west of England and of France; and we shall soon be convinced that the sea has made ravages upon those coasts in proportion to its power, and has left them in a shape corresponding to the composition of the land, in destroying the softer, and leaving the harder parts[14].

[Footnote 14: M. de Lamblardie, ing�nieur des ponts et chauss�es, has made a calculation, seemingly upon good grounds, with regard to the wasting of a part of the coast of France, between the Seine and the Somme. This coast is composed of falaises, (or chalk cliffs, like the opposite coast of England), which are 200 feet high above the level of the sea, composed of strata of marl, separated by beds of flint. This coast is found to be wasted, at an average, at the rate of one foot per annum. We may thus perhaps form some idea of the time since the coast of France and that of England had been here united, or one continued mass of those strata which are the same on both those coasts.]

With those hard and rugged coasts of Britain and Ireland, let us contrast the east coasts; What a difference between these and the west side! Upon the west side, there are no sand banks left upon the coast; the mariner has nothing there to fear but rocks. It is otherwise on the east; here we find a tamer coast, and, in many places, a sandy bottom. On the west, nothing appears opposed to the storm of the ocean except the hardest and most solid rock; on the east, we find coasts exposed to the sea which could not have remained in a similar situation on the west. Let us but compare the two opposite coasts of England, viz. the promontory of Norfolk and Suffolk upon the one side, and Pembrokeshire and Carnarvonshire on the other, both similarly exposed, the one to the north east storm of the German sea, the other to the south west billows of the Atlantic. What a striking difference! The coast in the bay of Cardigan is a hard and strong coast compared with that of Norfolk and Suffolk; the one is strong schistus, the other the most tender clay; yet the soft coast stands protuberant to the sea, the harder coast is hollowed out into a bay; the one has no protection but the sands with which it is surrounded, the other had not remained till this day but for the protection of the most solid rocks of Pembrokeshire and Carnarvonshire, which oppose the fury of the waves.

The last general observation which I shall propose, has, for its subject, a more enlarged view than those now taken of the coast, a view indeed which is not so immediately the object of our observation, but which is nevertheless to be made most evident, by means of the others now considered. We have seen that the land exposed to the sea is destroyed, and the coast wasted more or less, in proportion to the wearing causes, and to the different resisting powers opposed to those causes of decay; we are now to make our observations with regard to the extent and quality of that which has been already destroyed, a subject which can only be conjectured at from the scientific view which may be taken of things, and from the careful examination of that which has been left behind upon the different coasts.

Our land is wasted by the sea; and there is also a natural progress to be observed which necessarily takes place on this occasion; for, the coast is found variously indented, that is to say, more or less, according as the land is exposed to this wasting and wearing operation of the sea, and according as the wasted land is composed of parts resisting with different degrees of power the destroying cause. The land, thus being worn and wasted away, forms here and there peninsulas, which are the more durable portions of that which had been destroyed around; and these remaining portions are still connected with the main land, of which they at present form a part.

But those promontories and peninsulas are gradually detached from the main land, in thus forming islands, which are but little removed from the land. An example of this we have in Anglesay, which is but one degree removed from the state of being a promontory. These islands again, in being subdivided, are converted into barren rocks, which point out to us the course in which the lost or wasted land upon the coast had formerly existed.

To be satisfied of this, let us but look upon the western coast of Scotland; from the islands of St. Kilda to Galloway, on the one side, and to Shetland on the other; in this tract, we have every testimony, for the truth of the doctrine, that is consistent with the nature of the subject. The progress of things is too slow to admit of any evidence drawn immediately from observation; but every other proof is at hand; every appearance corresponds with the theory; and of every step in the progress, from a continent of high land to the point of a rock sunk below the surface of the sea, abundant examples may be found. We do not see the beginning and ending of any one island or piece of country, because the operation is only accomplished in the course of time, and the experience of man is only in the present moment. But man has science and reason, in order to understand what has already been from what appears; and we have but to open our eyes to see all the stages of the operation although not in one individual object. Now, where the nature of things will not admit of having all and every step of the progress to be perceived in one object, an indefinite progression in the various states of different objects, showing the series or gradation from a continent to a rock, must form a proof in which no deficiency will be found.

I have given for example the coast of Scotland; but all over the world where there is a coast not covered with sand, or where it is exposed to the violence of the sea, it is the same. Take the map of any country, provided it be sufficiently particular, and you will see the breaking of continents or islands, first, into promontories or peninsulas; secondly, into islands which stand on the same solid basis with the continent; and, lastly, into rocks which are related to the islands, in like manner as those parasitical islands are related to the head lands and the shore. Here is a general fact, from the simple inspection of which we must conclude one of two things; either that those rocks and smaller islands, which we have termed parasitical, are in a state of progression, by which in time they will be joined to the main land, and form one continent; or that they are in a state of degradation, by which in time they will be made to disappear. There is no other supposition to be made; and, of that alternative, there is no room to hesitate a moment which to choose. This is not a matter of mere probability, it is the subject of physical demonstration. Should we find an old manuscript in a similar condition, we could not conclude with more certainty, that the deficient or intervening places had been destroyed, than we here conclude that the part which is now wanting, between the two remaining portions of the same rock or strata, had once connected those two portions, and had been destroyed by the operation of those causes which are every day employed in still increasing the breach.

Though over all the world, where the shore is washed bare by the sea, examples are to be found which require but to be seen to give compleat conviction, it is not in every place that the eye of a naturalist has been employed in taking this view of the coast; nor is it upon every occasion that enlightened philosophers of this kind have given their thoughts upon the subject. M. de Spallanzani has given us the following observations with regard to the coast of Italy[15].

[Footnote 15: Observations sur la Physique, etc. Juliet 1786.]

�Autant l'int�rieur du petit bourg de Porto-venere et les rochers qui l'environnent sont a l'abri des temp�tes, autant les parties ext�rieures sont expos�es aux coups de mer les plus violens, lorsqu'elles sont en proie au deux terribles vents d'Afrique et � celui du sud-est. Ce dernier en particulier soul�ve les flots avec tant de violence et � une telle hauteur contre les �cueils qui servent de d�fense � ce petit terrain, que la mer semble menacer de l'engloutir. J'ai �t� le t�moin d'un de ces orages, et quoique je fusse � l'abri de tout danger, je ne pourroit vous representer l'horreur que me fit �prouver ce spectacle. J'ai voulu prendre avec exactitude la hauteur moyenne de l'�levation des flots dans les plus violens coups de vent; et quand je vous en parlerai vous serez �tonn� de leur force et de l'�tendue de leurs effets. Les rochers qui sont � la partie m�ridionale de Porto-venere se rongent et se d�truisent peu-�-peu de m�me que les trois isles voisines Tiro, le petit Tiro, et Palmarin. On le remarque surtout dans cette dernier: les bords voisins de la terre ont une pente douce; ils sont couverts d'arbres et de plantes, tandis que la partie oppos�e est d�serte et inaccessible couverte de pr�cipices, de ruines et d'horreurs; les autres parties du rivage sont renferm�es par la rivi�re du ponent et par celle du levant, de m�me que celles qui s'approchent des c�tes de Provence. Il me paro�t que la mer a beaucoup gagn� sur le terre dans ces parages; et pour parler seulement de Palmarin, la plus grande, et la plus remarquable des trois �sles que j'ai nomm�es, je crois �tre suffisamment fond� pour conclure que la m�me pente facile et longue qu'on observe du c�te de la terre avoit aussi exist� du c�te de la mer; mais que cette derni�re avoit �t� d�truite par les orages, qui se sont succ�d�s pendant le cours de si�cles. La vue r�fl�chie de ces trois �sles me force � les regarder comme ayant �t� autre fois r�unies, et formant une �sle seule par leur r�union, ou plut�t comme une presqu'�le attenante � Porto-Venere.�

We have a still more interesting observation made upon this same coast of Italy, by a naturalist to whom the world is much indebted for his excellent remarks upon what he has, by his great industry, brought to light. I mean the Chevalier de Dolomieu; where-ever he goes, natural history reaps the benefit of the most enlightened observations. We are now to avail ourselves of his M�moire sur les Iles Ponces.

The pumice islands form part of a chain of land that may be traced forming a circular line from the cape Missene to the mount Circello at the other side of the Gulf of Gaeta. The islands of Ischia and Procida, which form part of this chain of land, might, from the inspection of the map, be allowed as having once formed a continuation of the land from the continent of Italy, even without the testimony of natural history, that traces this connection from the materials of those masses which now are separated.

The pumice islands form the middle part of that chain, and are the farthest removed from that continent of which it is probable they once formed a part. They are connected with the promontory of Missene on the one hand, as being of the same or similar volcanic origin, and on the other with mount Circello, by a curious circumstance in the island Zanone, which, but a little more of the devouring operation of the sea, would have concealed from our observation.

The island of Ventotiene, which is the nearest of them to Ischia, would appear to be the ancient island of Pendataria, in which Julia was confined. The marks of degradation in this island, I would wish to give in the Chevalier's own words, (p. 52.)

�Cette �sle continue � �tre devor�e par la mer, elle l'attaque dans toutes les parties de son contour, o� elle trouve peu de resistance, et elle ne cesse de creuser, principalement, tous les escarpemens du nord. Il paro�t, par les vestiges des antiquit�s qui sont sur la pointe dite di Nevola, que sous l'Empire de C�sar cette �sle avoit encore une �tendue plus consid�rable. Il s'y fait journellement des �boulemens; on peut pr�voir qu'elle diminuera progressivement, qu'elle se divisera, et que dans les temps � venir elle sera r�duite aux rochers de laves qui la supportent, et qui seuls peuvent r�sister, pendant une longue suite de si�cles, � tous les efforts des flots; ce ne sera s�rement pas la seule terre que le temps et la mer auront d�vor�e, et que les vicissitudes de la nature ont fait disparo�tre avant que l'histoire en ait pu constater l'existence.�

As the island of Ventotiene connects this group of the pumice islands with the continent of Missene, that of Zanone, on the other side, connects them with the continent at mount Circello. Here is a fact of which our author now gives proper evidence.

It would appear that Mount Circello is composed of an alpine limestone. But in the north end of the island of Zanone, the Chevalier de Dolomieu finds a small part of a similar limestone in vertical strata, closely united with the volcanic materials of the islands now under consideration. It is impossible that this portion of calcareous rock could be formed in its present situation, and we have but to examine nature in order to be convinced that this limestone part had been once continued from Mount Circello. Here again I beg leave to give this author's own words, (page 141.)

�Cette r�union de deux mati�res aussi diff�rentes par leur origine que le font celles qui forment l'Isle Zanone, est une circonstance des plus singuliers. La pierre calcaire ne contient point de coquillages; sa densit� sa duret�; son odeur f�tide annonce une origine ancienne; elle n'est point form�e par un d�p�t de nouvelle date; elle diff�re des pierres calcaires-coquilli�re qui recouvrent les volcans du Padouan et du Vicentin, et de celles qui se sont m�l�s avec les produits du feu dans les volcans �teintes de la Sicile: les laves ici reposent sur elle: elle paro�t donc ant�rieure � l'�poque des irruptions qui ont �lev� les �sles ponces. Par sa nature elle est semblable aux pierres du Mont Circ�, et � celles de l'int�rieure de l'Apennin; il semble que cette portion de montagne calcaire, abstraction faite des mati�res volcaniques qui lui sont r�unies, a appartenu � quelqu'unes des montagnes qui d�pendent de la chaine qui traverse l'Italie; car il n'est pas possible que ni elle ni le Mont Circ� ayent �t� form�s seules et isol�s ainsi que nous les voyons. Mais quand ont-ils �t� d�tach�es? �toient-ils d�j� isol�s lorsque les feux ont commenc� la formation des �sles ponces? ou seroit-ce la m�me r�volution qui les auroit s�par�s du continent, et qui a op�r� le d�sordre que nous voyons dans ces �sles volcanique? On ne peut former sur toutes ces questions que des conjectures bien vagues.�

Our present inquiry is only with regard to the operation of those causes which we now perceive to be acting upon the coasts of the land; which must be considered as having been operating for a long time back, and which must be considered as continuing to operate. One example more I wish to give, not only as it is much to the purpose, and properly described, but because it contains the natural history of a coast well known from the circumstance of the Giant's Causeway which it contains; a coast composed of stratified chalk indurated and consolidated to a species of marble or lime-stone, and of great masses of basaltes or columnar whin-stone. Now, though our present object is not the formation of land, yet, knowing the mineral constitution of this land, the coast of which we are considering as having been worn by the action of the sea, the view here to be given, of the white marble and basaltic cliffs, is satisfactory in the highest degree. It is from Letters concerning the Northern Coast of the County of Antrim, by the Reverend William Hamilton, A. M.

�The chalky cliffs of the island of Raghery, crowned by a venerable covering of brown rock, form a very beautiful and picturesque appearance as one sails towards them; and, if the turbulence of the sea does not restrain the eyes and fancy from expatiating around, such a striking similitude appears between this and the opposite coast, as readily suggests an idea that the island might once have formed a part of the adjoining country, from whence it has been disunited by some violent shock of nature.

�You, to whom demonstration is familiar, will wonder to see two shores, seven or eight miles asunder, so expeditiously connected by such a slender and fanciful middle term as apparent similitude; and yet the likeness is so strong, and attended with such peculiar circumstances, that I do not entirely despair of prevailing even on you to acknowledge my opinion as a probable one.

�It does not appear unreasonable to conclude, that, if two pieces of land, separated from each other by a chasm, be composed of the same kind of materials, similarly arranged, at equal elevations, these different lands might have been originally connected, and the chasm be only accidental. For, let us conceive the materials to be deposited by any of the elements of fire, air, earth, or water, or by any cause whatever, and it is not likely that this cause (otherwise general) should in all its operations regularly stop short at the chasm.

�The materials of which the island of Raghery is composed are accurately the same as those of the opposite shore; and the arrangement answers so closely, as almost to demonstrate, at first view, their former union. But to explain this more clearly, it will be necessary to give you a general sketch of this whole line of coast.

�The northern coast of Antrim seems to have been originally a compact body of lime-stone rock, considerably higher than the present level of the sea; over which, at some later period, extensive bodies of vitrifiable stone have been superinduced in a state of softness. The original calcareous stratum appears to be much deranged and interrupted by those incumbent masses. In some places it is depressed greatly below its ancient level; shortly after it is borne down to the water's edge, and can be traced under its surface. By and by it dips entirely, and seems irretrievably lost under the superior mass. In a short space, however, it begins to emerge, and, after a similar variation, recovers its original height.

�In this manner, and with such repeated vicissitudes of elevation and depression, it pursues a course of forty miles along the coast from Lough Foyle to Lough Larne.

�It naturally becomes an object of curiosity to inquire what the substance is from which the lime-stone seems thus to have shrunk, burying itself (as it were in terror) under the covering of the ocean: And, on examination, it appears to be the columnar basaltes, under which the lime-stone stratum is never found; nor indeed does it ever approach near to it without evident signs of derangement.

�Thus, for example, the chalky cliffs may be discovered a little eastward from Portrush; after a short course, they are suddenly depressed to the water's edge, under Dunluce Castle, and, soon after, lost entirely in passing near the basalt-hill of Dunluce, whose craigs, near the sea, are all columnar. At the river Bush the lime-stone recovers, and skims a moment above the level of the sea, but immediately vanishes in approaching towards the great basalt promontory of Bengore, under which it is completely lost for the space of more than three miles.

�Eastward from thence, beyond Dunsaverock Castle, it again emerges, and, rising to a considerable height, forms a beautiful barrier to White Park Bay and the Ballintoy shore. After this it suffers a temporary depression near the basalt hill of Knocksoghy, and then ranges along the coast as far as Ballycastle Bay.

�Fairhead, standing with magnificence on its massy columns of basaltes, again exterminates it; and once again it rises to the eastward, and pursues its devious course, forming, on the Glenarm shores, a line of coast the most fantastically beautiful that can be imagined.

�If this, tedious expedition have not entirely worn out your patience, let us now take a view of the coast of Ragery itself, from the lofty summit of Fairhead, which overlook it. Westward we see its white cliff rising abruptly from the ocean, corresponding accurately in materials and elevation with those of the opposite shore, and like them, crowned with a venerable load of the same vitrifiable rock. Eastward, we behold it dip to the level of the sea, and soon give place to many beautiful arrangements of basalt pillars which form the eastern end of the island, and lie opposite to the basaltes of Fairhead, affording in every part a reasonable presumption that the two coasts were formerly connected, and that each was created and deranged by the same causes extensively operating over both.

�But it is not in these larger features alone that the similitude may be traced; the more minute and accidental circumstances serve equally well to ascertain it.

�Thus, an heterogeneous mass of freestone, coals, iron-ore, etc. which forms the east side of Ballycastle Bay, and appears quite different from the common fossils of the country, may be traced also directly opposite, running under Rathlin, with circumstances which almost demonstrably ascertain it to be the same vein.

�What I would infer from hence is, that this whole coast has undergone considerable changes; that those abrupt promontories, which now run wildly into the ocean, in proud defiance of its boisterous waves, have been rendered broken and irregular by some violent convulsion of nature; and that the island of Ragery, standing as it were in the midst between this and the Scottish coast, may be the surviving fragment of a large tract of country which, at some period of time, has been buried in the deep.�

Besides this argument of the gradation from a continent of land to a bare rock, we have another from the consideration of those rocks themselves, so far as these could not be formed by nature in their present state, but must have been portions of a greater mass. How, for example, could a perpendicular mountain, such as St. Kilda, have been produced in the ocean? Of whatever materials we shall suppose it formed, we never shall find means for the production of such a mass in its present insulated state. Let us take examples of this kind near our coast, and of known rocks. Staffa and Ailsa, on the west coast, and the Bass, upon the east, are mountains of either whin-stone or granite, similar to many such mountains within the land; and they are perpendicular around, except perhaps on one part. It is demonstrable that such basaltic rock as contains zeolite and calcareous spar, as most of our whin-stones do, could not have been the eruption of a volcano, consequently those rocks must have been masses protruded in a fluid state, under an immense cover of earth at the time of their production; and they could not have risen immediately out of the sea, with all their various minerals, their veins and cutters, their faces and their angles.

In like manner, the east coast of Caithness is a perpendicular cliff of sand-stone, lying in a horizontal position, and thus forming a flat country above the shore. But along this coast there are small islands, pillars, and peninsulas, of the same strata, corresponding perfectly with that which forms the greater mass. Now, shall we suppose those strata of sand-stone to have been formed in their place, and to have reached no farther eastward into the sea?--It is unsupposable. Or, shall we conceive that the sea, which has made such depredations in land composed of much more solid materials, had spared this, and had not wasted much more than that now pointed out by the ruins which remain?--Impossible; we must suppose that there had once existed much land where nothing now is found but sea. But, if we are to suppose much to have been wasted, where shall we stop in this process of restoring continents? That is the question now to be discussed.

With this view, let us now turn our attention to the north-west coast of Europe, in consulting the general as well as the most particular maps. Upon the one extremity of Britain, we find Cornwall separating it as it were from the main land; and, from this promontory, the Scilly Isles pointing out what had been destroyed in that direction, which is here to be considered as the line of greatest resistance. But what a quantity of the soft materials, or less resisting parts on either side, has been destroyed! Upon the other extremity of Britain, we find the country of Scotland, forming itself into promontories and islands, and those islands and rocks pointing out to us what had been the former extent of our continent and land around. But, in following this connection of things, we cannot refuse to acknowledge that Ireland had formerly been in one mass of land with Britain, in like manner as the Orkneys had been with Scotland[16].

[Footnote 16: I have the most satisfactory evidence of this fact, in finding the schistus of Galloway and of England in the opposite coast of Ireland, corresponding to its direction in stretching from the coasts of Britain.]

It will be still less possible to refuse the junction of England with the continent of France; the testimony of that peculiar body of chalk and flint, which borders each of those opposite coasts, forms an argument which is irrefragable. Now, in order to complete our continent, we have only to connect the Shetland islands with the coast of Norway. But this is a notion which, however probable it may appear, is not proposed as a fact immediately supported by natural appearances; it is only to be considered as an enlarged view in which we may contemplate the operations of this earth upon a more extended scale; one which may be conceived as a step in our cosmogeny, and one which, while it illustrates the theory of the earth already given, is by no means required in order to confirm a theory founded upon appearances which leave no manner of doubt.

There are two different directions in which we may observe the destruction of our land to proceed; in the one of these, the basis of our continent is diminished by the incroachment of the sea; in the other, again, it is the height of the land above the level of the sea that is lowered. We have been considering the incroachment of the sea upon the continent; let us now examine how far there may also appear sufficient documents, by which we may be led to conclude a long progress in time past, for the destruction of the solid mass of earth above the sea, without diminishing its basis.

If we shall suppose this earth composed of horizontal strata, and of one level surface, without the least protuberance remaining by which we might be informed of what had been removed by time in the operation of second causes, we should be ignorant of every thing of cosmogeny but this, That the strata of the globe had been originally formed (by the sea) in the same shape as we had found them on the surface of the land. But this is not the shape of the surface of our continent: We have every where abundance of eminences, sufficient to give us great information with regard to what had passed in former periods of time, if the strata of the globe were in that regular shape which they had originally assumed in being deposited at the bottom the sea.

The strata, however, are not in that regular shape and position from whence we might learn, by examining the remaining portions, what had been carried away from the surface in general; they are found variously inclined to the horizon; and this we find both occasioned from the fracture and flexure of those bodies, thus changed from their natural horizontal state. Thus, though there are in many places immense masses of strata cut off abruptly, and exposed to view, without the remainder appearing, we cannot from hence form any estimate of the general quantity of destruction; at the same time, it must be evident, from a general inspection, that there has been an immense quantity removed; and that an immense time had been required in bringing about those revolutions of things, which are not done by violent changes, but by slow degrees.

Besides that general conclusion with regard to the destruction of the strata, there is also in many places a demonstration of that fact, from a measured minimum of the quantity which had been removed. It is to the mining business chiefly that we are indebted for that demonstration of which we now shall give an example.

The coal strata, about Newcastle upon Tyne, dip to the south-east at the rate of one in twelve, or thereabouts. This is but little removed from the horizontal position; at the same time, the strata come all up to the soil or surface in a country which is level, or with little risings. But in those strata there is a slip, or hitch, which runs from north-east to south-west, for 17 or 18 miles in a straight line; the surface on each side of this line is perfectly equal, and nothing distinguishable in the soil above; but, in sinking mines, the same strata are found at the distance of 70 fathoms from each other. Here therefore is a demonstration, that there had been worn away, and removed into the sea, 70 fathoms more from the country on the one side of this line, than from that on the other. It is far from having given us all the height of country which has been washed away, but it gives us a minimum of that quantity.

The examination of what is commonly called a secondary country is not sufficient to give us an idea of the immense operation of time in wearing the surface of this earth. It is not that those countries of inferior hardness and elevation have been spared in the course of time, but because we have not, in those levelled countries, such great remainders, by which we are to judge the quantity of what is lost. In the alpine country, again, though it be the same system of things with that which takes place in the lower country, the revolution of things is more marked for our view; and the ravages of time, in destroying the solid parts of the globe, in order to make soil of that which is removed, may be seen in all the steps of that important operation; whereas, in the more level countries, the scale of elevation is imperceptible, and that of time is so slow as renders our examination fruitless. It is the Alps, therefore, chiefly that we are to take for an example, in tracing this operation of nature upon the surface of this earth, and forming some idea of the course of time that must have flowed during that operation in which the height of our land had been diminished.

On whatever side we approach the Alps, we find some great river discharging the waters which had been gathered above, and with that water all the waste of earth and stone which had been made among those lofty masses of decaying rock. Now, we find this river running in a valley proportioned, in general, to this vehicle, in which is travelled the wreck of ruinous mountains. Spacious plains attend those mighty streams; and, tho' sometimes we find the greatest rivers much confined between approaching hills of solid rock, the valley opens again, and, on the whole, is always corresponding to the current of water which has successively run in all the quarters of this plain. Here a question occurs; Has this valley been made by the operation of the river itself, or has it been the effect of other causes? Let us now resolve that question.

If the valley was made for the river by any other natural cause, either we should tell by what means this work had been performed, or all reasoning upon the subject is at an end, and fancy substituted in its place. If again the river be considered as the means employed by nature in making this valley, then all the solid parts between the bounding mountains must have been removed, and the fertile plains must have been formed by the water depositing those materials which we find in the soil, and which had come originally from the solid mountains. There is no occasion to enter into any argument to prove this fact; nobody that examines the matter will find any reason to doubt; and it would be as unreasonable for those to doubt who have not examined, as for those who find no reasonable subject of doubt to disbelieve.

We are now to suppose the great river to have formed the valley and extensive plain in which the water runs,--a valley corresponding to the grandeur of the river by which it has been formed. But, as we ascend this great valley, we find other valleys branching from this main valley; and, in all those subordinate valleys, we find rivers corresponding in like manner with the magnitude of the valley. Here, therefore, is infinitely more than a single river, and a valley corresponding to the river; here is a system of rivers and of valleys, things calculated in perfect wisdom, or properly adapted to each other.

Now it is just as easy, by our theory, to explain this system of rivers and valleys, as it is to understand the single appearance of a river and a valley. But it is only in this manner that such a complicated operation, of a series in rivers and their valleys, is to be explained; and we can neither suppose the land to be formed with this intention by a supernatural cause, nor imagine any other natural cause so arranging things, upon the surface of the earth, as to form this perfect system, which holds of nothing but itself; a system in which is manifested wisdom, so far as all the parts are properly adapted to each other, and thus made to answer that intention which is so visible in the economy of this world.

The direction of the principal valleys of the Alps, or every mountainous region of the globe, may be considered as proceeding from the centre of that region to the plain country in which each river is to terminate; each secondary river with its valley then branches from the primary as from a stem, consequently runs in a direction perpendicular or inclined to the other. But the secondary rivers also have their branches; and subordinate branches still are branched. In thus tracing rivers and their branchings, we come at last to rivulets that only run in times of rain, and at other times are dry. It is here I would wish to carry my reader, in order to be convinced, with his proper observation, of this great fact,--that the rivers, in general, have hollowed out their valleys.

The changes of the valley of the main river are but slow, the plain indeed is wasted in one place, but it is repaired in another, and we do not perceive the place from whence that repairing matter had proceeded. Therefore, that which here appears does not immediately suggest to the spectator what had been the state of things before the valley had been hollowed out, or before that plain, through which the river runs so naturally as being in the lowest place, was made. But it is otherwise in the valley of the rivulet; no person can examine this subject without seeing that the rivulet carries away matter which cannot be repaired except by wearing away some part of the mountain, or the surface of that place upon which the rain, which forms the stream, is gathered. In those rivulets, or their little plains, we see the detached parts remaining in the soil, and also the place from whence those detached parts were taken. Here we need no long chain of reasoning from effect to cause; the whole operation is in a manner before our eyes. In this case, it requires but little study to replace the removed parts; and thus to see the work of nature, resolving the most hard and solid masses by the continued influences of the sun and atmosphere. In this state of things, we are easily made to understand how heavy bodies are travelled along the declivity of the earth, by means of water running from the height.

Such is the system of rivers and their valleys; nor is there upon the continent a spot on which some river has not run. But, in the Alps of Switzerland and Savoy, there is another system of valleys, above that of the rivers, and connected with it. These are valleys of moving ice, instead of water. This icy valley is also found branching from a greater to a lesser, until at last it ends upon the summit of a mountain, covered continually with snow. The motion of things in those icy valleys is commonly exceeding slow, the operation however of protruding bodies, as well as that of fracture and attrition, is extremely powerful.

To illustrate those operations of excavating the valleys of rivers and of thus undermining mountains which fall by their proper weight, I shall transcribe some descriptions of what is to be found among the Alps. But first I would wish to carry my reader to the summit of that country, to examine the state of that part which nothing can have affected but the immediate influences of the sun and air. After having thus formed some idea of the summit of this wasting country, we shall next examine the valleys through which the materials of the degraded summit must have travelled.

In order to give a proper idea of this central part of the Alps, which is so interesting a part in the natural history of the earth, M. de Saussure, in the plates of his Voyages dans les Alpes, tom. 2. has given us two views, the one in profile, the other in face, of the Mont-Blanc. I have caused copy those plates, which are necessary to be consulted in reading the following description of this centre of the Alps.

This author has taken much pains to form, to himself a proper idea of the object which we have now in view; and he gives a description of the Mont-Blanc as seen from the top of the Cramont. It is that description which I am now to transcribe[17].

[Footnote 17: Voyage dans les Alpes, tom. 2.]

� 910. �Le premier objet de mon �tude fut le Mont Blanc. Il se pr�sente ici de la maniere la plus brillante et la plus commode pour l'observateur. On l'embrasse d'un seul coup-d'oeil, depuis sa base jusqu'� sa cime, et il semble avoir �cart� et rejet� sur ses �paules son manteau de neiges et de glaces pour laisser voir � d�couvert la structure de son corps. Taill� presqu'� pic dans une hauteur perpendiculaire de 1600 toises, les neiges et les glaces ne peuvent s'arr�ter que dans un petit nombre d'�chancrures, et il montre partout � nud le roc vif dont il est compos�.

�Sa forme paro�t �tre celle d'une pyramide, qui presente au sud-est du c�t� du Cramont une de ses faces. L'arr�te droite de cette pyramide du c�t� du sud-ouest, monte au sommet, en faisant avec l'horison un angle de 23 � 24 degr�s. L'arr�te gauche du cot� du nord-est, monte au m�me sommet sous un angle de 23 � 24 degr�s, en sorte que l'angle au sommet est d'environ 130 degr�s.

�Cette pyramide paro�t elle m�me compos�e de grands feuillets triangulaires ou pyramidaux. Trois de ces grands feuillets ont leurs bases dans l'All�e-Blanche, et forment ensemble tout l'avant corps de la base de la pyramide. Chacun de ces feuillets, vu de l'All�e-Blanche, paro�t une grande montagne, je les ai d�crits dans le chapitre pr�c�dent sous le noms de Mont-P�t�ret, Mont-Rouge, et Mont-Broglia, � 830, 831, 834. Mais du haut du Cramont, on voit plus nettement leur forme, et leur ensemble, on distingue, par exemple, qu'ils sont eux-m�mes compos�s de grandes feuilles pyramidales; on voit que les injures du temps ont d�truit la pointe du Mont-Rouge, tandis que celles des deux autres pyramides sont demeur�es enti�res.

�Ces trois feuillets ne s'�l�vent pas jusqu'� la moiti� de la hauteur du Mont-Blanc; d'autres feuillets plus petits, situ�s derri�re et au-dessus d'eux, et plac�s sur deux lignes principales qui convergent au sommet, ach�vent de couvrir la face de cette grande pyramide. Ces feuillets sont tous de forme pyramidale; les plus petits sont les plus aigus; j'en ai mesur� plusieurs, dont l'angle au sommet n'�toit que de 70 degr�s. Tous, absolument tous, ont leurs plans parall�les � l'All�e-Blanche, et par cons�quent dirig�s du nord-est au sud-ouest.

�� 911. Quant � la mati�re dont est compos�e cette grande et haute montagne, toute sa cime et toute sa base, tant au centre que du c�t� du nord-est, sont indubitablement de granit; mais le c�t� sud-ouest de la base, ou le Mont-Broglia que nous avons vu de pr�s, � 834, est d'une pierre moins dure, m�lang�e de schorl, de feldspath, de mica, de quartz gras et de pyrites.

�On voit tr�s-bien du haut du Cramont que cette partie de la base n'est point du granit; sa couleur est d'un brun rouge�tre, elle ne se termine point par des arr�tes vives et nettes, n'est point compos�e de grandes tables planes. Ce font cependant des feuillets pyramidaux, mais petits et press�s les unes contre les autres; � mesure qu'ils s'approchent du sommet, et par cela m�me du coeur de la montagne, ils perdent leur couleur rouge, leurs angles deviennent plus vifs, leurs tables plus grandes et plus planes, et enfin pr�s de la cime, et � la cime m�me, ce sont de vrais granits parfaitement caract�ris�s. On peut donc conclure, que le corps entier du Mont-Blanc, et m�me ces bases avanc�es du c�t� de l'Italie, sont toutes de granit, except� la base de l'arr�te ext�rieure du c�t� du sud-ouest.

�� 912. La montagne qui touche le Mont-Blanc du c�t� du nord-est, et qui, vue de Gen�ve, forme en quelque maniere le premiere escalier en descendant de la cime, est aussi compos�e de tables de granit qui paroissent dirig�es du nord-est au sud-ouest. Mais la sommit� qui suit celle-ci en tirant toujours au nord-est, et qui forme le second escalier, paro�t avoir quelques feuillets tournans autour de son corps pyramidal, comme les feuillets d'un artichaux, et comme j'ai d�peint l'aiguille du Midi, tome I. pl. 6. En tirant plus encore au nord-est, on reconno�t les Jorasses que nous avons vues du haut du Tal�fre, � 637, elles paroissent d'ici, apr�s le Mont-Blanc et ses escaliers, les sommit�s les plus �lev�es de toute cette cha�ne, et elles semblent r�sulter de l'assemblage de plusieurs suites de feuillets pyramidaux convergents vers leur sommet. En g�n�ral toutes les cimes �lev�es que l'on peut distinguer dans cette chaine, depuis le Mont-Blanc jusqu'au col Ferret, sont soutenues par des augives compos�es d'une ou de plusieurs suites de feuillets pyramidaux appuy�s les uns contre les autres; les ext�rieures ont leurs bases dans le fond de la vall�e, et les int�rieures remontent par degr�s jusqu'au haut des cimes. Les deux escaliers du Mont-Blanc sont les seules sommit�s qui n'aient pas des augives de ce genre.

�� 913. Je demande � present quelle id�e on peut se faire de l'origine de ces feuillets plans et de toutes ces pyramides grandes et petites qui r�sultent de leur assemblage, si on ne les consid�re pas comme les restes ou les noyaux les plus durs des couches qui out r�sist� aux ravages du temps, tandis que les parties interm�diaires, qui les lioient entr'elles, out �t� d�truites par ces m�mes ravages.

�Mais jusqu'� quel point la crystallization a-t-elle contribu� � d�terminer ces formes pyramidales? doit-on consid�rer le Mont-Blanc ou telle autre de ces aiguilles, comme un �norme crystal? C'est une question de th�orie que j'examinerai ailleurs. Quant � pr�sent je me contenterai de conclure, que la face m�ridionale de la cha�ne centrale des Alpes est, comme la face septentrionale de cette m�me cha�ne, compos�e, pour la plus grande partie, de couches de granit �-peu-pr�s verticales, et dirig�es pour la plupart du nord-est au sud-ouest.�

This theoretical question of our author is so properly connected with the natural history which he has here given us, that it is not difficult to resolve it in the most satisfactory manner.

Here is an enormous mass of granite, the origin of which we are not now inquiring after, but the causes of its present form. The internal part of this granite subsists in a state of the most perfect solidity; the external again is evidently in a decaying state. This is a fact which we learn from the nature of feldspar, of which granite is in part composed; this crystallised substance is every where decomposed, where long exposed to the atmosphere. But it is not this gradual decay of the mass of granite perishing equably from its external surface, and resolved into some of its component parts, that we are here to consider; it is only mentioned to show that the mass of granite is subject to decay, when exposed to the influence of the atmosphere, like every other compound mineral body, and to lose that perfect solidity which we find in the centre of the mass.

We find the granite masses not only subject to decay from the external surface, by the decomposition of the feltspar, or the dissolution of its constituent parts, but also liable to be separated into blocks of different degrees of regularity, commonly rectangular or approaching to the rhombic shape. This is the consequence, either of larger veins and fissures, filled with matter which is still more dissolvable than is the substance of the granite, or else by imperceptible crevices or cutters, into which the atmospheric influences gradually insinuate, and form at last a visible separation.

In examining the tops of granite mountains, or where this rock is exposed to the weather, we may perceive those two species of decay proceeding together. The external surface of the stone, where there is a sufficient mixture of feltspar, is separating into grains which form a species of sand, being nothing but the particles of granite separating by means of the decaying sparry part. But a similar progress may be observed, from the external surface penetrating in lines the mass of solid rock, and dividing that mass into the rectangular blocks into which those exposed places are gradually resolved.

Now the tops of all those mountains are formed into an assemblage of pyramids, declining in height from the central pyramid; and all those pyramids are again in like manner subdivided into lesser pyramids. But the smallest of those pyramids are no other than the rectangular blocks into which those granite masses always separate by the influence of the atmosphere.

It will now be evident, that those mountains, thus resolving into separate blocks, must acquire this series of pyramidal constructions; for, in every particular mass of mountain, there must be a central part, from which the separated blocks cannot be removed, while those around, or towards the sides, are detached by the swelling water upon freezing, and separated from the more central masses which are thus the latest of being removed.

It is impossible to see this series of pyramidal relics, without at the same time perceiving that manner of formation, by the gradual resolution of the solid mass of granite, as it comes to be exposed in succession to the influences of the atmosphere, which M. de Saussure has termed les ravage du temps.

But if it be in this manner, that time wastes the solid masses of this globe; and if all the solid masses of the earth have acquired their solid state by the same means, i.e. by heat and fusion, as is maintained in the present theory, we should find similar pyramidal mountains formed of different materials. Now there can be nothing more different than masses of lime-stone and those of granite. But pyramidal mountains are equally formed of those two different materials. In plate V, under the letter B, may be seen the calcareous pyramids which are near the col de la Seigne, and which in plate VI. are represented under the letter G.

Here is a view of the summit of the Alps, from whence we may be allowed to draw the most important conclusions in favour of our theory.

This summit is of solid granite, a mass in which there is no stratification, such as is to be perceived in all the other masses of those alpine regions. With regard again to the extent of this mass of granite, its basis is about two leagues in breadth, by at least thrice that space in length; and now we are to consider in what shape this mass of granite presents itself to our view.

The summit of Mont Blanc, which may be considered as in the centre of this mass, is a pyramid; and this great central pyramid is surrounded by a number of other great pyramids of the same kind. The points of those pyramids are extremely lofty; and, having sides often vastly steep, if not perpendicular, those colossal pyramids rise from the icy valleys in such a shape as has given occasion to their being named needles. Thus we find the whole space of this granite mass consisting of a mixture of icy valleys, and pyramidal rocks on which hardly any thing rests.

Now, these lofty rocks or pointed mountains must have been either originally formed of that shape, or posteriorly hewn out by the hand of nature, gradually wasting mountains in the course of time, and operations of the surface. If it is by the first that we are to explain the present state of things, then observation is superfluous, and our reasoning is at an end; for, when even observation should not contradict the proposition, which it actually does, it would be useless, as it can afford no data from a former state, which is supposed to have been no other than it is at present; and reasoning cannot be admitted if we have no data. Therefore, if we are to reason upon the subject, we are obliged to admit, that nature must have hollowed out of the solid rock all those pyramidal mountains, and a system of inclined valleys carrying the ice from the summits.

Let us now reason from our principles, in order to see how far the present appearances of things would naturally result from those wasting causes acting upon a mass of granite, of a given basis and of sufficient height, during a space of time which is unlimited.

We are to suppose our mass of granite without any structure except that of the veins and cutters, formed by the contraction of the solid mass in cooling. Now, those separations will naturally give direction to the operation of the wasting causes, whether we consider these as chymical or mechanical. Hollow tracts would thus be formed in the solid mass; in those hollow ways would flow the water, carrying the detached portions of the rock; and those hard materials, by their attrition upon the solid mass, would more and more increase the channels in which they move. Thus there would be early formed a system of valleys in this rock, and among those valleys a number of central points, or summits over which no running water would carry hard materials to operate upon the solid rock over which it flows.

Here therefore, in the nature of things, is placed the rudiments of our needles, those colossal pyramids which acquire height gradually as the valleys widen, and whose apices may arrive at an angle of a certain degree of acuteness. But what a waste of rock to have formed all those needles which we find rising from the icy valleys round Mount Blanc!

Upon the supposition that this had been the origin of those pyramidal mountains, it must be evident, that there is a ne plus ultra of acuteness to which the apex of a pyramid would in time arrive; and that then the decaying summit would tumble by the lump alternately, and regain the acuteness of its point. Now, if this be the case, although we cannot see the process, which is too slow for human observation, we should actually find them in all the stages of this progress. But this is precisely the state in which the summits of those mountains are to be found. M. de Saussure gives a view of one of those pyramids, which will serve to illustrate this subject in the most perfect manner. It is from the Montanvert that this object is to be perceived. (Voyages dans les Alpes, vol. 2.).

These high peaks of solid rock demonstrate the manner in which those enormous masses of mountains are degraded, and also the means which are employed by nature for that purpose; but this scene, however well represented, is too far removed, in its appearance, from the ordinary mountains of this earth, to satisfy the doubts of every reader or to generalise a principle which must be universal in the system of this earth. We therefore have occasion for a mean, by which the extreme of those alpine summits shall be generalised or connected with our low inclined plains; and, on this occasion, I will give M. de Saussure's most excellent description of the Breven. Nothing can better suit our present purpose than the subject of this natural history; and I am persuaded that most readers will be better informed by the description of this naturalist, than they would be by their own observation.

��. 639. J'ai d�j� plusieurs fois nomm� cette montagne, qui est situ�e imm�diatement au-dessus du Prieur� de Chamouni, du c�t� du nord-ouest: elle est li�e par sa base avec les Aiguilles-rouges, dont j'ai aussi parl� dans le premier volume. Mais sa cime est nue, isol�e, arrondie sur les derri�res, et coup�e � pic du c�t� de Chamouni. C'est � tous �gards une des montagnes les plus int�ressantes pour un naturaliste.

�J'y montai pour la premiere fois en 1760, et je ne crois pas qu'aucun naturaliste l'e�t visit�e avant moi; j'y retournai l'ann�e suivante; j'y allai encore en 1767, et j'y montai enfin pour la derni�re fois en 1781, afin de v�rifier mes anciennes observations, et de me mettre en �tat d'en donner une description plus exacte.

�� 640. On peut du Prieur� monter au sommet du Br�ven et redescendre dans le m�me jour, mais c'est une course p�nible, car il faut au moins cinq heures pour monter, et la pente est extr�mement rapide. On peut cependant faire � mulet le premier tiers de cette mont�e. Comme je voulus avoir le tems d'observer tout avec soin, j'y destinai deux jours, et j'allai coucher le premier jour dans un chalet, nomm� Plianpra, qui, en partant du Prieur�, est aux deux tiers de la hauteur totale de la montagne.

�En montant � Plianpra, on fait pr�s des trois quarts du chemin sur des d�bris tomb�s et roul�s du haut de la t�te du Br�ven. La colline m�me sur laquelle est b�ti le village du Prieur� n'est compos�e que des d�bris de cette montagne; ces d�bris ont d�bouch� par une gorge que nous traversons en montant, et se versant ensuite � droite et � gauche, ils ont pris la forme d'un c�ne, dont le sommet est au milieu de cette gorge. Les collines de ce genre et de cette forme se rencontrent bien fr�quemment dans les vall�es bord�es par de hautes montagnes.

�Ces d�bris, qui ne viennent pas seulement de la t�te du Br�ven, mais de ses flancs et de sa base, sont des roches feuillet�es m�lang�es de quartz, de mica et de feldspath dans toutes les proportions imaginables. De ces diff�rentes proportions naissent diff�rens degr�s de duret�, depuis le granit feuillet� le plus dur jusques � la roche micac�e la plus tendre.

�� 641. Les rochers au pied desquels on passe avant de gravir la mont�e rapide et herb�e qui aboutit � Plianpra, sont compos�s d'une roche feuillet�e assez dure, dont les couches bien parall�les aux veines int�rieures de la pierre, suivent la direction de l'aiguille aimant�e et sont tr�s-inclin�es � l'horison.

�Le chalet de Plianpra est situ� au milieu d'une assez grande prairie en pente douce du c�t� de la vall�e de Chamouni, et domin�e du c�t� oppos� par les rocs nus qui forment les sommit�s de la cha�ne du Br�ven. Du bord de cette prairie, on a une tr�s-belle vue du Mont-Blanc, de la vall�e de Chamouni et des glaciers qui y aboutissent. Ces m�mes objets se pr�sentent avec bien plus d'�clat de la cime du Br�ven; cependant la vue de Plianpra m�riteroit bien que ceux qui n'auroient pas la force ou le courage d'aller jusques � la cime, montassent du moins jusque l� pour s'en former une id�e.

�Comme je ne voulois monter sur le Br�ven que lendemain, j'employai le reste de la journ�e � observer les environs du chalet. J'examinai surtout avec soin des rochers situ�s � une demi-lieue au nord au-dessus du chalet, qui de loin paroissent color�s en rouge, comme plusieurs sommit�s de cette cha�ne: c'est par cette raison qu'elle porte le nom d'Aiguilles-rouges.

�� 642. Je trouvai que c'�toient encore des granits vein�s, m�lang�s de quartz, de feldspath, de mica et de fer qui colore la pierre en se d�composant au-dehors: cette teinte p�n�tre m�me quelquefois assez avant dans l'int�rieur. Ces rochers sont divis�s par couches bien distinctes, �-peu-pr�s verticales, et dans la direction de l'aiguille aimant�e, comme celles que j'avois observ�es au-dessous du chalet. Ces couches sont coup�es par des fentes �-peu-pr�s perpendiculaires � leurs plans, et qui sont pour la plupart parall�les � l'horison, de maniere que ces rochers se trouvent ainsi divis�s en grandes pieces de forme �-peu-pr�s rhombo�dale. Les veines m�mes int�rieures de la pierre sont aussi tr�s-bien prononc�es, et exactement parall�les � ses couches; observation g�n�rale et de la plus grande importance, parce qu'elle prouve que ces couches sont bien de vraies couches, et non point des fissures produites fortuitement par la retraite ou par un affaissement in�gal des parties du rocher. Ces veines sont dessin�es sur le fond blanc de la pierre des feuillets minces de mica noir�tre; elles sont tant�t planes, tant�t ond�es, mais toujours r�guli�res et parall�les entr'elles, except� l� o� il se rencontre des noeuds; encore reprennent-elles leur direction apr�s en avoir fait le tour. Comme le mica s'y trouve en petite quantit�, la pierre est dure, et ne se brise qu'� grands coups de marteau. Lorsqu'on l'observe de pr�s dans sa cassure, on voit que les petites lames ou �cailles de mica sont constamment couch�es dans le sens des veines de la pierre. Ces m�mes �cailles n'ont presque aucune adh�rence entr'elles, en sorte que les feuillets dont la pierre est compos�e, n'adh�rent entr'eux que par les points o� il ne se trouve point de mica.

�� 643. Je me demandois � moi-m�me, en observant cette pierre, s'il �toit possible qu'elle e�t �t� form�e dans cette situation verticale; si ces �cailles incoh�rentes auroient pu venir s'attacher � ces murs verticaux, et si le mouvement des eaux, clairement indiqu� par le tissu feuillet� de la pierre, n'auroit pas d� les d�tacher et les faire tomber � mesure qu'elles se formoient. Je me demandois encore, si les fentes qui coupent ces feuillets, perpendiculairement � leurs plans, ne dateroient point d'un tems ou ces couches auroient �t� horisontales, et n'auroient point �t� produites alors par le poids et l'affaissement in�gal des parties de la pierre. Mais pour admettre cette supposition, il faudroit expliquer comment ces bancs, d'abord horisontaux, ont pu se redresser; pourquoi ce redressement a �t� si fr�quent, si r�gulier, etc. etc. Je r�serve pour un autre tems la discussion de ces grandes questions; mais je ne crois pas inutile de faire apercevoir la liaison qu'ont avec la th�orie des observations si minutieuses en apparence.

�En faisant ces r�flexions, je retournai au chalet de Plianpra o� je passai la nuit sur de la paille que j'avois fait �tendre aupr�s du feu, parce que la soir�e �toit extr�mement fra�che.

�� 645 On commence � monter par de jolis sentiers peu inclin�s, pratiqu�s le long d'un grand rocher semblable � ceux que j'avois observ�s la veille. On a ensuite le choix de monter, ou par des pentes couvertes de rocailles un peu fatigantes, ou par des gazons extr�mement rapides. Ceux-ci paroissent d'abord plus agr�ables et moins p�nibles; cependant ces gazons sont si serr�s et si glissans, qu'ils en deviennent dangereux, au moins pour ceux qui n'ont pas l'habitude des montagnes. Ces rocailles sont d�bris de roches feuillet�es, semblables � celles que l'on rencontre en montant du Prieur� � Plianpra.

�� 646. B. Au bout d'une heure de marche, on arrive au pied d'un rocher assez escarp�, qu'il faut escalader pour parvenir � la cime de la montagne. C'est une roche micac�e, mais qui contient cependant assez de quartz pour avoir de la consistance. Elle se s�pare par feuillets si d�cid�s, que sans employer d'autre instrument que mes mains, j'en d�tachai une dalle, qui avoit sept pieds de hauteur sur quatre de largeur, et � peine un pouce dans sa plus grande �paisseur.

�J'avois quelque desir de descendre de-l� au pied des grandes tables verticales qui composent la t�te du Br�ven, pour les observer de pr�s et comparer ainsi leur base avec leur cime; mais de cet endroit la chose est impossible, la pente est d'une telle rapidit� qu'une pierre m�diocrement grosse, que je mis en mouvement, roula avec beaucoup de vitesse, en entra�na d'autres, celles-ci d'autres, et elles form�rent enfin un torrent de pierres qui se pr�cipita avec un fracas mille fois r�p�t� par les grands rochers du Br�ven.

�Comme donc je ne pouvois pas descendre, je montai par le passage ordinaire, qui est une esp�ce de couloir ou de chemin�e ouverte, adoss�e � un rocher presqu'� pic, de 40 ou 50 pieds de hauteur. Bien des curieux sont venus jusques au pied de ce passage sans oser le franchir; mais je vis en revenant qu'� un demi-quart de lieue plus au nord, on trouve un autre passage extr�mement commode, qui m�ne au m�me but, et qu'il faut par cons�quent toujours pr�f�rer.

�Ce rocher une fois escalad�, on monte par une pente douce, sans danger et sans fatigue, jusqu'au sommet du Br�ven.

�� 646. C. En montant le long du bord, du c�t� de Chamouni, j'eus un plaisir inexprimable � contempler les magnifiques tables de granit dont est compos�e toute la t�te de cette montagne. Car bien que les �cailles du mica noir�tre dont cette roche est m�lang�e, soient parall�les entr'elles et lui donnent ainsi quelque ressemblance avec une roche feuillet�e, cependant la quantit� de quartz et de feldspath qui entrent dans sa composition, son extr�me duret�, le peu de disposition qu'elle a � se fondre dans le sens de ses feuillets, la placent, sinon pour le nomenclateur, du moins pour le naturaliste, dans la classe des vrais granits[18]; et le parfait parall�lisme de ces feuillets avec les faces des grandes tables, ou des grandes divisions du rocher, d�montre que ces tables sont des couches, et non des parties s�par�es par des fissures accidentelles.�

[Footnote 18: �La d�nomination de granit vein� que j'ai, � ce que je crois, employ�e le premier, a paru tr�s-heureuse � quelques naturalistes, et a, au contraire, souverainement d�plu � quelques autres. Un de ces derniers pr�tend que ce que je nomme granit vein� n'est qu'un amas de gravier graniteux, et par cons�quent une esp�ce de gr�s grossier. Mais je voudrois que ceux qui de bonne foi pourroient croire que j'aie commis une erreur aussi grossi�re et aussi fr�quemment r�p�t�e, observassent les granits du Br�ven; et j'en enverrais volontiers � ceux d'entr'eux que le souhaiteroient. Lorsqu'ils verroient que les parties de quartz et de feldspath qui entrent dans leur composition, ont tous leurs angles vifs et tranchans, que ces parties sont intimement unies entre elles et emp�t�es les unes avec les autres, comme dans les granits en masse; que leur coh�rence est aussi grande que dans ces derniers granits, et que cette roche n'en diff�re absolument, comme je l'ai d�j� dit, que par le parall�lisme qu'observent entr'elles les lames rares de mica dont elle est m�lang�e: je suis persuad� qu'ils reconno�troient qu'elle a tous les caract�res essentiels du ranit, qu'elle doit avoir la m�me origine, et qu'en un mot elle est au granit proprement dit, ce qu'une pierre calcaire feuillet�e est � une pierre calcaire dans laquelle on ne distingue point de feuillets.�]

�L'extr�me r�gularit� de ces tables ach�ve de d�montrer que ce sont de v�ritables couches. Leurs plans qui sont ici � d�couvert dans une hauteur perpendiculaire de plus de 500 pieds, sont parfaitement suivis, comme taill�s au ciseau, dirig�s tous comme l'aiguille aimant�e, et verticaux, � quelques degr�s pr�s dont ils s'appuyent contre le corps de la montagne. On s'assure en montant que cette structure est celle de la montagne enti�re; on voit les profils d'une infinit� de ces couches, on passe sur les sommit�s de ces tranches verticales, et on les voit se prolonger dans cette m�me direction tout au travers de la montagne. Or je demande si un naturaliste qui aura observ� cet ensemble et ces d�tails pourra regarder cette montagne comme le produit du concours fortuit de grains de sable agglutin�s entr'eux.

�Ces tables sont coup�es un peu obliquement � leurs plans par des fentes dont la plupart sont �-peu-pr�s horizontales et d'autres tr�s-inclin�es � l'horizon. La pierre se trouve ainsi tr�s-fr�quemment coup�e en parall�l�pip�des obliquangles. Ces m�mes fentes rendent raison, d'une observation que j'avois faite en 1776. En examinant avec une bonne lunette, depuis une fen�tre du Prieur�, les faces verticales des couches de la sommit� du Br�ven, j'avois remarqu� un grand dieze [Illustration] bien nettement �crit sur la face de la montagne, je le vis de pr�s en 1781, et je reconnus qu'il �toit form� par quatre de ces fentes qui se coupoient obliquement.

�� 647. La cime de la montagne est une pointe mousse, coup�e � pic du c�t� de la vall�e de Chamouni et arrondie de tous les autres c�t�s. Cette t�te est enti�rement couverte de d�bris et de blocs confus�ment entass�. On est �tonn� de trouver l� ces d�bris, car cette cime est absolument isol�e, et s�par�e par de larges et profondes vall�es des sommit�s qui la surpassent en hauteur: il semble que ces d�bris n'aient pu tomber que du ciel; mais quand on les examine avec soin, on voit qu'ils sont du m�me genre de pierre que la montagne elle m�me; et que tous leurs angles font vifs, leurs faces planes et leur forme souvent rhombo�dale. On reconno�t donc par l� que les parties sup�rieures de la montagne, qui sont plus expos�es aux injures de l'air et qui ne sont pas assujetties par des masses situ�es au-dessus d'elles, se d�litent et se separent. Je trouvai cependant sur la cime une pierre d'une espece diff�rente; c'�toit une roche compos�e de schorl noir en aiguilles, de quartz et de grenats; sa forme �toit exactement rhombo�dale. Mais ce genre de pierre se rencontre assez souvent en filons dans les roches feuillet�es et dans les granits vein�s; il est donc vraisemblable que le filon auquel ce fragment avoit appartenu s'est d�truit avec la partie sup�rieure du rocher, du moins n'en ai-je pu trouver aucun indice dans la partie solide de la montagne.

�L'admirable r�gularit� des couches de cette cime �lev�e m�rite l'attention des amateurs de la g�ologie, et la vue qu'elle pr�sente d�dommageroit seule de la peine d'y monter.

�� 648. Mon but principal dans la premiere course que je fis au Br�ven �toit de prendre de l� une id�e juste des glaciers de la vall�e de Chamouni, de leur forme, de leur position, et de l'ensemble des montagnes sur lesquelles ils sont situ�s. Comme cette montagne est post�e �-peu-pr�s au milieu de la vall�e de Chamouni, en face du Mont-Blanc et vis-�-vis des principaux glaciers qui en descendent, c'�toit certainement un des meilleurs observatoires que l'on p�t choisir dans cette intention. J'y montai par le jour le plus beau et le plus clair; c'�toit mon premier voyage dans les hautes Alpes, je n'�tois point encore accoutum� � ces grands spectacles; en sorte que cette vue fit sur moi une impression qui ne s'effacera jamais de mon souvenir.

�On d�couvre tout-�-la-fois et presque dans un seul tableau les six glaciers qui vont se verser dans la vall�e de Chamouni, les cimes inaccessibles entre lesquelles ils prennent leur naissance; le Mont-Blanc surtout, que l'on trouve d'autant plus grand, d'autant plus majestueux, qu'on l'observe d'un lieu plus �lev�. On voit ces �tendues immenses de neige et de glaces, dont, malgr� leur distance, on a peine � soutenir l'�clat, ces beaux glaciers qui s'en d�tachent comme autant de fleuves solides qui vont entre de grandes for�ts de sapins, descendre en replis tortueux, et se verser au fond de la vall�e de Chamouni; les yeux fatigu�s de l'�clat de ces neiges et de ces glaces se reposent d�licieusement ou sur ces for�ts, dont le verd fonc� contraste avec la blancheur des glaces qui les traversent, ou dans la fertile et riante vall�e qu'arrosent les eaux qui d�coulent de ces glaciers.�

Our object at present is not to see the degradation of that great mass of granite out of which have been hewn, by the hand of time and influences of the atmosphere, these lofty pyramids which surround Mont-Blanc; it is to see the degradation of that immense mass of vertical or highly inclined strata, out of which that great mass of granite rises; and it is to understand the conical and rounded forms which are to be perceived more or less in all the inferior mountains, where apparently the degradation has come to a stand, and where the surface is actually employed in vegetation, or in maintaining the system of living bodies in this world.

How high those vertical strata may have been erected, or how much may have been wasted of that mass in forming the mountains and their valleys, is a question which it is impossible to resolve: It is evident, however, that this quantity must have been very great. In the Mont-Rosa we find those strata at present in the horizontal situation, as high as the summits of those granite pyramids that overlook the mass of vertical strata which we are now considering; and, in those mountains of Rosa, the valleys are most profound. It is therefore most reasonable to suppose, that the mass out of which the Breven and all the other mountains had been formed, was once as high, at least, as the summit of Mont-Blanc. It is altogether inconceivable, that this mass of vertical and horizontal strata could have been formed, either originally, or by any mineral operation, into the present shape of things; therefore, we must look out for another cause.

Let us now suppose them degraded by the hand of time, and all their moveable materials transported in the floods; In what state would they be left for our examination?--Here is a question that must decide the theory of those mountains; for, if it is not possible to conceive the present appearances as arising from any other cause than this gradual degradation which we see operating at present, we must conclude that this is the system of nature established for the purpose of this world. But this is the very state in which they are found; every where the solid parts are going into decay, and furnishing those heaps of earth and stones that form the slopes by which we ascend from step to step. Wherever earth and stones may lie, there they are found to form a bank for vegetation; whenever these loose materials are carried away to a lower; station, the more solid parts above are still decaying in order to furnish more. There is not one step in all this progress, (of the summit of the solid mountain forming earth and stones, and travelling to the sea) that is not to be actually perceived, although it is only scientifically that man, who reasons in the present moment, may see the effect of time which has no end.

The summit of the granite pyramids of Mont-Blanc, the summit of the Breven, that of the Saleve[19], and of every little hillock upon the surface of the earth, attest this truth, that there is no other natural means by which this end may be attained. It is true, indeed, that geologists every where imagine to themselves great events, or powerful causes, by which these changes of the earth should be brought about in a short space of time; but they are under a double deception; first with regard to time which is limited, whereas they want to explain appearances by a cause acting in a limited time; secondly, with regard to operation, their supposition of a great debacle is altogether incompetent for the end required. How, for example, accumulate the debris of the Breven, as we have now seen, upon the summit of that mountain, by the force of running water? But this is only one of a thousand appearances that proves the operations of time, and refutes the hypothesis of violent causes.

[Footnote 19: See Part II. chap. 30.]

From the top of those decaying pyramids to the sea, we have a chain of facts which clearly demonstrate this proposition, That the materials of the wasted mountains have travelled through the rivers; for, in every step of this progress, we may see the effect, and thus acknowledge the proper cause. We may often even be witness to the action; but it is only a small part of the whole progress that we may thus perceive, nevertheless it is equally satisfactory as if we saw the whole; for, throughout the whole of this long course, we may see some part of the mountain moving some part of the way. What more can we require? Nothing but time. It is not any part of the process that will be disputed; but, after allowing all the parts, the whole will be denied; and, For what?--only because we are not disposed to allow that quantity of time which the ablution of so much wasted mountain might require.

The Theory illustrated with a view of the Valleys of the Alps.

Such is the summit of the Alps, a body wasting by the influence of the elements, slowly changing, but in actual decay. This mass of granite is arrived at such a perfect state of degradation as leaves no trace of its original shape or height, from whence we might compute the quantity which has been lost, or time which had flowed in bringing about that event. We are now to take a view of the valleys that are formed at the same time that the mountains are degraded.

To the valleys of ice succeed those formed by water upon the same principle by moving the hard materials procured from the summits. Let us now begin at the bottom of one of those fertile valleys, and ascend, tracing the marks of time and labour in those operations by which the surface of the earth is modified according to the system of the globe.

(M. Bourrit[20], Nouvelle Description des Alpes.) �Saint-Maurice est entre le Rh�ne et une montagne; �Quoique la situation de Saint-Maurice paroisse l'exposer au malheur d'�tre un jour ensevelie sous les ruines des montagnes, cependant on ne vit pas ici avec moins de s�curit� qu'ailleurs: ce qu'il y a de plus � craindre, c'est la submersion du pays; ce malheur pourrait arriver si l'une ou l'autre des montagnes qui forment la gorge, venoit � tomber soit par un tremblement de terre, soit par des affaissemens consid�rables: cette gorge �tant �troite, le Rh�ne ne pourroit plus s'�couler il s'�tendroit n�cessairement au large, bient�t toute la vall�e jusqu'� Martigni, Sion m�me, rentreroit sous les eaux qui l'ont autrefois couvert, et tout ce pays ne formeroit plus qu'un lac, � moins que le Rh�ne ne se f�t jour sous les rochers renvers�s, comme il passe au travers de ceux qui semblent lui disputer le passage � cinq-lieues au-dessous de Gen�ve.�

[Footnote 20: M. Bourrit, etc.]

�Avant de p�n�trer dans le Vallais, il convient d'en donner une id�e g�n�rale: il forme cette partie des Alpes connue sous le nom d'Alpes Pennines; il contient non-seulement les plus hautes montagnes des Alpes, mais encore la plus longue vall�e qui il y ait en Europe, puis qu'elle a trente-quatre lieues depuis Saint-Maurice jusqu'�-la source du Rh�ne, qui la traverse dans toute cette �tendue: sa largeur est depuis demi-lieu jusqu'� une lieue et demie; sa direction suit le soleil. Outre cette vall�e, il y en a d'autres qui y viennent aboutir dans diverses directions: celle-ci sont enclav�es dans les deux cha�nes de montagnes qui bordent la grande vall�e; quelques-unes remontent � quatre lieues et m�me � six, dans les sinuosit�s que forment les rochers qui bordent les deux c�t�s du fleuve.�

To give an idea of these valleys which proceed to the icy tops of mountains, or to the high valleys of ice, I shall transcribe some descriptions of this country from the Tableaux de la Suisse Discours, etc. page 21.

�Route au Mont-Saint Bernard.

�On passe par Martigny pour aller au Mont du grand Saint-Bernard; cette ville est un d�p�t pour les marchandises qui vont et viennent d'Italie. Le ch�teau � c�t� de cette ville est situ� sur des rochers calcaires qui bordent la Drance dans cette partie; ce torrent prend sa source au Mont Saint-Bernard. On compte huit lieues de Martigny � l'Hospice situ� sur ce mont; � une demie-lieue on commence � monter insensiblement; le chemin est beau et peut se faire en voiture jusqu'au bourg Saint-Pierre.

�Le vaste base de ces monts accumul�s n'est qu'un compos� des d�bris des montagnes sup�rieures; on rencontre ici des granits roul�s, compos�s de quartz, de feld-spath, et de mica; des graviers et des sables provenant de la d�composition des granits des pierre calcaire grise, puis de grosse masses de granit arrondies, dont il seroit difficile d'assigner l'origine, puisque toutes les montagnes � port�e de la vue et qui forme cette gorge sont absolument de pierres micac�es par lits et par couches, ou schisteuses m�l�es de gros et petits rognons, de filons et de veines de quartz; elles font en g�n�ral toutes feu avec le briquet. Le chemin et la Drance qu'on passe et repasse plusieurs fois, occupent tout le fond de la vall�e qui devient fort �troite. On rencontre des pierres schisteuses, quartzeuses et sablonneuses, seules sans m�lange d'autre esp�ces.

�Saint-Branchier, bon village, est situ� entre des montagnes tr�s-hautes et tr�s-escarp�es compos�es des m�mes esp�ces des pierres schisteuses micac�es que les pr�c�dentes; elles sont de couleur bleu�tre, vue en grandes masses et inclin�es � l'horison; cette inclinaison suivant la m�me direction de ce c�t� ci de la Drance, et les couches se correspondant l'une � l'autre, on voit que ce torrent s'y est creus� un passage. En avan�ant, on trouve de l'ardoise feuillet�e bleue avec des veines de spath calcaire, ensuite une grande quantit� de granits et de pierres calcaires roul�es, sans que les montagnes environnantes changent d'esp�ces; les montagnes � l'est sont bien cultiv�es, rapportent diff�rentes sortes de grains, avant et apr�s avoir pass� orsi�re; on retrouve de l'ardoise entre ce village et Liddes et les derniers granits roul�s.

�La Drance est ici fort resserr�e et tr�s encaiss�e; ce n'est pas sans fr�mir qu'on s'apper�oit, quand on est sur deux morceaux de bois jet�s d'une roche � l'autre, appell�s ici pont, qu'on a un gouffre de plus de trois cent pieds au dessous de soi, il faut �tre sur cette esp�ce de pont pour s'en apercevoir et distinguer les diff�rents sinuosit�s trac�es sur chaque c�t� de cette roche du haut jusqu'en bas; ce sont autant de preuves des diff�rentes hauteurs o� l'eau a pass� avant de parvenir � sa profondeur actuelle.

�La dernier village qu'on rencontre, avant d'arriver au Saint-Bernard, est le bourg Saint-Pierre, on mont insensiblement jusqu'� ce village, et on ne peut plus se servir de voitures pour aller au-del�. Les montagnes sont plus rapides, il n'y a plus de chemin fait, et on n'en peut point pratiquer, moins a cause de la quantit� des rochers dont toute cette partie est couverte que par la difficult� de les entretenir ou de les renouveler chaque ann�e, parce que les torrens et les avalanches les detruiroient; de plus on ne pourroit y travailler que trois ou quatre mois de l'ann�e, les huit ou neuf autres mois le pays, au dela du bourg, �tant presque toujours couvert de neige. La truite ne remonte pas au-del� du bourge Saint-Pierre, elle se trouve arr�t�e par les cascades et chutes trop consid�rables de la Vassor�e qui va se jetter dans la Drance. Ce torrent sort encaiss� et resserr� dans le lit qu'il s'est creus�, provient d'un glacier qu'on rencontre en montant le Saint-Bernard qui porte le m�me nom. L'entr�e du valais est ferm�e et d�fendue de ce cot� par le lit de la Vassor�e; c'est le fosse le plus profond et le plus escarp� qui existe. Des ouvrage cr�nel�s et une porte sont plac�s � l'entr�e du bourg Saint-Pierre, nous avons donn� un dessin de la chute de ce torrent, on voit le travail des eaux dans le rocher qu'il a min� et o� il s'est ouvert un passage.

�On compte trois lieues de ce bourg � l'Hospice, sur le haut du Saint-Bernard; c'est le passage le plus fr�quent� pour communiquer du Bas-Vallais en Italie par le Pi�mont et la vall�e d'Aost; le transport des marchandises ne se fait qu'� dos de mulets et de chevaux; c'est du produit de ces transports que vivent la plupart des habitans qui sont des deux c�t�s de ce mont; celui des fromages, qui est la principale production de ces hautes Alpes, fait le plus fort article. On ne rencontre sur cette route que des rochers entass�s les uns sur les autres, entre lesquels on passe par mille d�tours, en suivant les petits vallons qu'ils forment. Des torrents des eaux y roulent et s'y pr�cipitent de tous c�t�s; on voit dans ces bas, de bois de sapins m�l�s de quelques pins et puis des m�l�zes; ils diminuent insensiblement, leurs v�g�tation est moins vigoureuse, les arbres sont plus rares les derniers qu'on rencontre sont des m�l�zes � une heure de Saint-Pierre. Plus loin, on ne voit plus que des buissons bas et rabougris; au bord de quelque ruisseau ou torrent ce sont des aulnes ou vergnes; le dernier arbrisseau que nous avons vu, entre les m�l�zes et les aulnes, est un sureau sans fruit. Les p�turages, l'herbe et le gazon suivent la m�me progression. Ce n'est-que dans quelques endroits, d'o� les eaux n'on pas entra�n� une restant de terre v�g�tale, qu'il se voit un gazon fin, menu et serr�; de petites fleurs, aussi bases que ces gazons, nuanc�es des plus belles et des plus vives couleurs, y forment des groupes de la plus grande beaut�; des mousses non moins curieuses que vari�es, couvrent et colorent quelques parties de rochers; le reste n'offre � l'oeil que d'�normes masses de rochers, entrecoup�s de fentes, de crevasses; des pierres culbut�es et amoncel�es dans les fonds, qui font en partie couverts de ne�ge.

�A une demie lieue de l'Hospice dans une vallon assez large pour une pareille hauteur, nomm� les Envers des Foireuse, on rencontre une �norme quantit� de pierre roul�es qui remplissent presque tout le haut de ce vallons. Cet amas de pierres provient des glaciers et des hauteurs qui descendent du Mont-Velan, qui est la partie la plus �lev�e du groupe de montagnes, qui forment le grand Saint Bernard. L� sont des neiges et des glaciers de cette partie, fournit aussi la Drance qui va se jetter dans le Rh�ne au dessous de Martigny. On ne voit de ces pierres roul�es qu'en cet endroit, elles viennent directement des glaciers, elles ont �t� charri�es par les eaux qui en viennent, et ne peuvent avoir pris leur forme que par les m�me causes, dont nous avons parl� ci-devant dans l'observation faite en Savoie sur les pierres roul�es; elles sont toutes, ainsi que les rochers au-dessus, d'ou-elles proviennent, compos�es de parties micac�es-argilleuses, plus ou moins m�l�es de partie de rognons, de veines et de filons de quartz, par lits et par couches irr�guli�res, plus ou moins �paisses. Les parties micac�es de ces pierres sont vari�es de diff�rentes nuances, tirant sur le gris, le bleu, le verd, et le jaune; ces nuances sont quelquefois m�l�es. Tous les rochers composans ce c�t� de montagne tourn� au nord, sont de la m�me esp�ce. Nous n'y avons pas vu un seul granit, c'est-�-dire, une pierre compos�e de petites masses irr�guli�res de quartz, m�l�es et agglutin�es, avec des parties micac�es argilleuses, et quelquefois m�lang�s de feldspath. Parmi ces pierres, il y en a quelques-unes provenant du m�me filon, qui contiennent de la pyrite cuivreuse dans un filon de quartz.

�Nous avons dit precedement que c'�toit entre Orfi�re et Liddes que nous avions vu des derniers granites roul�s, on n'en rencontre plus dans toute le reste de la route jusqu'au haut du Mont Saint-Bernard. Les rochers, qui dominent ce sommet, ne sont pas composes de granites, et quoiqu'on ne puisse aborder jusqu'� leurs plus grands �l�vation, on peut juger de leurs esp�ces, par les masses qui s'en pr�cipitent.

�(Page 35.) Malgr� la chaleur qu'il avoit fait le jour de l'arriv�e au Saint-Bernard, la nuit fut froide; le lendemain (31 Juillet) le haut de la montagne �toit envelopp� de nuages �pais, mais tranquilles, il n'y avoit point d'agitation dans l'air on assuroit qu'il faisoit beau au-dessous de ce sommet; nous f�mes visiter le revers meridional de la montagne qui conduit au val d'Aost; apr�s une demie heure de marche, nous fumes hors de cet atmosph�re sombre et humide, le soleil �toit chaud, le ciel pur et serein: on voyoit dans le lointain les sommets des plus hautes montagnes envelopp�s dans les nuages comme le Saint-Bernard: les sommets les plus � port�e �toient d�couverts et �clair�s par le soleil; ces rochers termin�s en pointe, en pyramides et en aiguilles, sembloient s'�lancer dans la r�gion pure de l'�ther: des vallons profonds, des �cueils, et des pr�cipices effrayants les entouraient. Toutes ces masses sont, comme dans la partie oppos�e de la montagne, des pierre schisteuses, argilleuses et micac�es: le plupart schisteuses, c'est-�-dire par feuillets, par lits ou par couches diff�remment inclin�es, le toute m�l� de veines et de parties quartzeuses, de couleurs vari�es, mais les verd�tres dominent: il y a de plus sur la hauteur de ce revers des masses et des blocs prodigieux, sans m�lange, de quartz blanc et grenu � sa superficie, lesquels, au premier coup-d'oeil, paroissoient �tre de marbre de Carare; � quelque distance c'est un chaos immense de blocs de pierres de toutes grandeurs, jet�s, culbut�s, entass�s dans la plus grand confusion; c'est la m�me esp�ce de pierre micac�e; il faut que des sommets, des rochers prodigieux se soient �croul�s pour avoir produit un pareil d�sordre qui ressemble � la destruction d'un mond.

�(Page 40.) On trouve aux environs du couvent quelques schistes argilleux ou ardoises grises feuillet�es d�truites � moiti�. On ne voir nulle part de ces ardoises sur pied ou formant des masses attach�es au sol; il faut que les couches ou les lits de ces ardoises, qui avoient �t� form�s et plac�s sur ces hauts, ayent �t� d�truits et renvers�s par le temps.

�Enfin toute cette montagne, une des plus hautes des Alpes Poenines, qui conserve des neiges et de glaces permanentes, est compos�e en g�n�ral de pierres et de roches schisteuses, dont les couches et les lits sont plus on moins sensibles et inclin�s, et d'une grande duret�. Leurs parties constituantes sont un mica argilleux dont les lames ou les parties sont plus ou moins grandes et brillantes et diversement color�es: elles sont travers�es de filons et de veines m�l�s de rognons et de globule de quartz ordinairement blanc, quelquefois vitreux, transparent, opaque ou grenu: nous n'y avons vu des granits que sur le penchant de la montagne; ils y �toient isol�s et roul�s. Quelqu'un qui aura plus de temps, plus de loisir, d�couvrira peut-�tre d'o� ces masses proviennent[21].�

[Footnote 21: M. de Saussure, in his 2d volume of Voyages dans les Alpes, has shown the origin of these travelled granites, and traced the way by which they have come.]

We have here a picture of one of those valleys which branch from, or join the main valley of the Rh�ne. In this subordinate valley, there is the most evident marks of the operations of water hollowing out its way, in flowing from the summits of the mountains, and carrying the fragments of rocks and stones along the shelving surface of the earth; thus wearing down that surface, and excavating the solid rock. On the summit of the mountain, again, there is an equal proof of the operation of water and the influences of the atmosphere continued during a long succession of ages. It is impossible perhaps to conjecture as to the quantity of rock which has been wasted and carried away by water from this alpine region; the summits testify that a great deal had been above them, as that which remains has every mark of being the relicts of what had been removed, and moved only by those operations which here are natural to the surface of the earth. Let us now abstract any consideration of that quantity above the summits of those mountains, as a quantity which cannot be estimated; and let us only consider all the cavity below the summits of those ridges of mountains to have been hollowed out by those operations of running water which we now have in view.

In taking this view of the mountains on each side which supply the water of the Rh�ne, what an immense quantity of stones, of sand, and fragments of rock, must have travelled in the bed of that river, or bottom of that valley which receives the torrents coming from the mountains! The excavation of this great valley, therefore, will not be found any way disproportionate to that which is more evident in the branches; and, though the experience of man goes for nothing in this progress of things, yet, having principles in matter of fact from whence he may reason back into the boundless mass of time already elapsed, it is impossible that he can be deceived in concluding that here is the general operation of nature wasting and wearing the surface of the earth for the purposes of this world, and giving the present shape of things, which we so much admire in the contrast of mountains and plains, of hills and valleys, although we may not calculate with accuracy, or ascribe to each particular operation every individual appearance.

With a view to corroborate what has been here alledged of the valley of the Rh�ne, I would beg leave to transcribe still more from the same author. From the immense masses of horizontal strata remaining upon both sides of the valley of the Rh�ne, with a face broken off abruptly, we shall find the most perfect evidence of that which had been carried away in the course of time, and in the forming of those valleys.

�(Page 49.) Route au Bains de Loiche. Nous quitterons un moment les bords du Rh�ne pour visiter les bains de Loiche, afin de ne pas revenir sur nos pas. De Sierre on passe par Clar� et Salge, en laissant le Rh�ne sur la droite; tout ce terrain est calcaire et fort pierreux. A Faren (villages qui ne font point sur les cartes) on commence � monter la montagne de Faren; le chemin est fort rapide et mauvais, et dure une bonne heure et demie; on trouve sur le haut de cette montagne de blocs de granit compos�s de quartz, de feld-spath, et de mica, d'o� viennent-ils? On ne voit que des roches calcaires et point de montagne plus �lev�e au-dessus; on passe par un bois de pins, on parvient enfin � un escarpement � pic, dont on n'a point d'id�e pour la hauteur; on reste stup�fait de voir le gouffre qu'on a devant soi, et on ne pr�voit pas trop comment on parviendra dans ce fond, o� la vue a peine � distinguer la Dala, gros torrent qui y pr�cipite ses eaux. On a taill� � grands frais un sentier tortueux dans cette roche toute calcaire; On a eu soin de garnir le cot� scabreux du sentier avec des pierres ou des garde fou, pour rendre ce passage moins effrayant; ces pr�cautions ne peuvent gu�rir de la crainte de voir tomber d'�normes quartiers de rochers suspendus au-dessus de soi, ils sont fendus et crevass�s partout, et menacent de se pr�cipiter � chaque instant; on ne peut m�me s'emp�cher de remarquer qu'il y en a qui sont tomb�s nouvellement! Ce sont des mineurs Tiroliens qui ont fait cet ouvrage, ainsi que le passage du Mont-Gemmi.

�Quand on est descendu au tiers environ de cet �norme fond, on passe sur les d�combres de cette vaste montagne, et par un bois de pins et de sapins; la vue ne perce pas dans ce fond t�n�breux, on entend plut�t le bruit du torrent qu'on ne l'apper�oit. Ayant eu occasion de voir et d'examiner par la suite ces bas et le pied de cette �tonnante montagne calcaire, nous avons vu dans plus d'un endroit qu'elle pose, et que ces fondements sont un lit de schistes argilleux ou d'ardoises feuillet�es sans m�lange, que ce lit est d�truit et se d�truit dans diff�rens endroits, qu'il est inclin� et affaiss� dans d'autres, et que c'est la destruction qui a occasionn� la chute d'une partie de cette montagne; elle est par-tout � pic de ce c�t�, et a subi successivement ces renversements qui paroissent plus anciens les unes que les autres, car ces d�bris sont plus ou moins couverts de bois, d'arbres, et de productions v�g�tales.

�On continue la route � mi c�te au travers de ces d�bris. Le sommet de ces montagnes �clair�s par le soleil, �toit peint de rouge, de jaune, de blanc, de bleu, et de noir, dans les endroits o� les eaux avoient coul� par-dessus, ils ressemblent de loin � des murailles, des tours, des forts, et des fortifications de diff�rentes formes plac�es pour se d�fendre contre des ennemis qui viendroient par les airs. Les neiges qu'on apper�oit dans diff�rents endroits, produisent des chutes d'eau, des cascades, dont partie se r�duit en vapeurs avant d'atteindre le bas: le haut des montagnes qu'on voit de l'autre c�t� de ce vallon, est �galement calcaire, elles sont plus basses, couverts d'arbres et de sapins; au lieu que celles dont il est question sont nues et arides; elles sont le s�jour des neiges et sont partie de la Gemmi.

�Une de plus haute montagnes du Vallais, et situ�e sur une terrain tr�s-�lev�, est la Gemmi; elle fait partie de la grande cha�ne qui s�pare le Canton de Berne du Vallais. Elle est remarquable, � cause de l'importance du chemin qu'on y a pratiqu�, des grandes difficult�s qu'il a fallu surmonter, et qu'elle est la seule communication entre les deux Cantons. Nous parlerons de ce chemin, apr�s avoir d�crit la nature de ce prodigieux rocher. La Gemmi est la partie la plus haute de cette cha�ne qui commence aux galleries; elle est en general calcaire. On commence a monter insensiblement en sortant de Loiche; on traverse beaucoup de p�turages; on voit quelques champs de seigle qui �toient encore sur pied et � moiti� verts, des bosquets et de petits bois de sapins. Des masses consid�rables des rochers, des monceaux de pierres entass�es descendues des hauteurs, couvrent cette superficie qui devient d'autant plus rapide qu'on approche plus du pied du rocher: cette pente qui est au pied de l'escarpement et de toutes les autres montagnes, est form� des pierres et des sables qui tombent des hauts et produisent, � la longue, des talus formes en pain de sucre, adosses contre les parties escarp�es; les plus grosses pierres roulent et se pr�cipitent plus bas, servent de point d'appui aux nouveaux mat�riaux qui s'y arr�tent, augmentent la hauteur des talus, en �largissant les basis, et finissent par devenir des montagnes tr�s consid�rables qui ont augment� en raison de la quantit� des d�bris qu'ont pu fournir les parties plus �lev�es; c'est ce qu'on nomme montagnes de troisi�me formation, compos�es des ruines de celles qui dominent ces talus; ces �boulemens sont ordinairement plus fertiles, plus couverts de v�g�taux, d'arbres et de for�ts, sur-tout s'ils sont compos�s de diff�rentes esp�ces de d�bris. Nous avons d�j� vu que les montagnes calcaires sont elles-m�mes assises sur des couches et des lits d'ardoise ou de schiste, qui, par l'arrangement de leurs feuillets et de leurs couches, paroissent aussi avoir �t� arrang�s et form�s successivement; quelle est donc la base primitive sur laquelle sont appuy�es et reposent ces masses qui �tonnent l'imagination, � quelle profondeur faudra-t-il l'aller chercher? Si nous concevons la formation et la mani�re dont se sont accrues et �lev�es ces troisi�mes montagnes, pouvons-nous imaginer comment se sont arrang�es celles qui sont si �lev�es au-dessus d'elles, ce tout que rien ne domine. C'est en examinant en consid�rant ces grands spectacles que ces r�flections nous viennent; nous nous arr�tons, pour continuer � d�crire ce que nous avons vu et remarqu�, qui est la t�che que nous nous sommes impos�e.

�En arrivant au pied de l'escarpement, le premier objet qui frappe la vue, ce sont des bancs de schistes ou d'ardoises bleu�tres, m�l�s de larges filons de quartz qui forment la base, et les fondemens sur lesquels est �lev� ce mur de pierres calcaires. Car cette roche est �lev�e de m�me � pic; ce lit d'ardoises est un peu inclin� vers le couchant, ainsi que tout ce qui repose dessus; la destruction de ce lit a caus�, ainsi qu'aux galeries, la chute des rochers sup�rieurs, et leur a occasionn� cet �-plomb. Avant ces �boulements, ces couches schisteuses devoient �tre d�couvertes � une grande hauteur, �tre expos�es aux injures du tems et des saisons, se d�truire et se d�composer plus ais�ment. Peut-�tre que l'enveloppe calcaire les couvroient enti�rement, et que ces schistes n'ont commenc� � se d�truire qu'apr�s la ruine de la pierre calcaire. Actuellement ces schistes sont enterr�s et couverts; ce n'est qu'en peu d'endroits qu'on les apper�oit; appuy�s soutenus et couverts par ces immenses d�bris en talus, ce sont des contre forts qui les aiderons � supporter plus longtemps les prodigieuses masses sous lesquelles ces schistes sont ensevelis. Nous allons placer par ordre les diff�rentes substances, telle qu'elle se pr�sentent en montant.

�1. Base de schiste ou d'ardoise feuillet�e bleu�tre, travers�, de larges filons de quartz. On ne voit, on ne peut estimer son �paisseur dont partie est enterr�e.

�2. Imm�diatement dessus pose la pierre calcaire, elle est d'une grain fin, serr�, couleur grise-jaun�tre, ainsi que toute le reste.

�3. Des filons de diff�rentes �paisseurs, d'un spath calcaire jaun�tre.

�4. Quelques petits filons ou renules de schiste pur.

�5. De la pierre calcaire d'un grain plus grossier.

�6. D'autres couches d'un grain plus fin.

�7. Couches de pierres calcaires m�l�es d'une quantit� suffisante de sable pour faire feu avec le briquet, sans cesser de faire effervescence avec les acides.

�8. De petits filons ou couches ondoyantes de spath.

�9. De la pierre calcaire dans laquelle sont d�pos�s des esp�ces de noyaux oblongs, quelques fois par couches, mais sans suite, compos�s d'un sable fin de couleurs gris�tre, plus blanc que la pierre calcaire, tr�s-durs, faisant feu au briquet, et sans effervescence avec les acides.

�10. On retrouve encore des couches minces sablonneuses m�l�es de parties calcaires.

�11. D'autres de pierre calcaire compacte et d'une �paisseur consid�rable.

�12. Alternativement de moins compactes. Dans l'une de ces couches il y a de la pyrite vitriolique d�compos�, qui teint en jaune les parties du rochers sur lesquels a flu� la d�composition martiale.

�13. Quelques filons de spath jaun�tre, entrem�l�s de veines de schiste pur, ne faisant pas effervescence.

�14. De la pierre calcaire.

�15. Des schistes m�l�s de parties calcaires.

�16. De la pierre calcaire pure.

�17. De larges filons de spath calcaire jaun�tre m�l�s de quartz, faisant feu au briquet, et une peu d'effervescence.

�18. De la pierre calcaire pure grise, plus fonc�e que dans le bas.

�19. Des couches calcaires jaun�tres.

�20. Enfin tout le haut n'est que pierre calcaire grise et d�natur�e. Cette partie sup�rieure du monte est fort �tendue. Tout ce qui est sur le local qui va en pente assez douce vers le milieu, n'a pas �t� assujetti � de roulis et � des frottemens, il n'y a que la longueur du tems qui l'ait d�grad�, et lui ait imprime le caract�re de la v�tust�. On ne voit que des pierres calcaires, elles sont remplies de trous, de fentes, et de crevasses; beaucoup, paroissent poreuses comme de la la pierre ponce grossi�re; le s�jour des neiges des eaux, la gel�e, et l'intemp�rie des saisons a tout fait. On voit de tous c�t�s que l'eau s'y infiltre et s'y perd. L'arrangement de cette esp�ce de pierre par couches, facilite l'entr�e des eaux dans l'int�rieur de la montagne pour aller donner naissance � des sources, � des torrents, et quelquefois � d'assez fortes rivieres qui sortent du pied de ces montagnes calcaires; lors de la fonte des neiges, l'eau ne se verse point des sommets de ces sortes de montagnes comme de dessus les autres esp�ces de rochers qui absorbent moins les eaux. Dans le milieu de ce haut il y a un petit lac d'un grand quart de lieue de long de forme ovale, ou se rassemblent les eaux des neiges fondues; il n'y a point d'issues � ce lac, ses eaux sont absorb�es, et se perdent dans l'int�rieur de la montagne; il n'y avoit que peu de glace alors sur ce lac, mais il y avoit encore beaucoup de neiges aux environs; un glacier est sur la droite, se prolonge et va fermer le sommet du vallon o� est Loiche; c'est le m�me glacier qu'on apper�oit derri�re les sources chaudes. Deux aiguilles de rocher en c�ne, fort hautes s'�l�vent au-dessus du sommet; elles sont toujours couvertes de neiges: leur ressemblance et leur proximit� a donn� le nom de Gemmi Jumeaux, � cette montagne--On voit � ses pieds � une profondeur immense le village de Loiche, qui paro�t �tre tout au pied du rocher; il faut cependant une grand heure et demie pour s'y rendre, tant la hauteur diminue le point de perspective. Le chemin qui est pratiqu� dans ce rocher, y a �t� par-tout taill�; il le contourne certains endroits, dans d'autres il est creus� de fa�on qu'il forme une vo�te couverte, et qu'on a le rocher suspendu au-dessus de soi. Il est rare de trouver l'occasion de pouvoir examiner de d�tailler avec autant de facilit� une montagne d'une pareille hauteur. A compter des galleries jusqu'aux glaciers de la Gemmi, ces rochers perpendiculaires et � pic ont plus de trois lieues d'�tendue; ils diminuent en hauteur � mesure que le pays s'�l�ve, et se confond dans les plus hautes alpes, qui sont surmont�es d'autre masses de rochers.

�De l'autre cot� du vallon, et vis-�-vis des montagnes qui forment celles de la Gemmi, est la montagne du midi, s�par�e par la Dala, torrent qui vient du glacier � la t�te du vallon, dont les eaux paroissent avoir creus� le lit �troit et profond. Cette montagne est calcaire comme la Gemmi, et paro�t en avoir fait partie: je n'ai pu v�rifier nulle part si elle �toit pos�e sur des schistes: tout est dans un grand bouleversement sur sa pente qui est fort rapide. A environs trois quarts de lieue des bains, un sentier fort difficile, qui passe sur les d�combres de cette montagne et dans des bois de sapins fort obscurs, conduit par un pente fort rapide a un rocher perpendiculaire, comme sont presque tous ceux du canton on y trouve des �chelles appuy�es contre; on parvient � la premi�re, en grimpant par les avances et les saillies du rocher; d'autres roches facilitent le moyen d'arriver � la seconde; on trouve ainsi sept �chelles dont quelques-unes sont fort hautes, et par lesquelles on se guide au sommet de ce rocher; on est bien surpris d'y trouver un terrain en pente, o� il y a des champs labour�s et des vignes qui entourent le village d'Albinien, dont les habitans ont plac� ces �chelles pour raccourcir le chemin qui conduit � Loiche, o� ils vont vendre leurs denr�es.

�Nous quittons les bains de Loiche pour nous rapprocher du Rh�ne: on repasse par Inden, on ne trouve ensuite que des pierres, des rochers, des escarpemens; c'est un chemin des plus mauvais jusqu'au bourg de Loiche; c'est pour �viter ce chemin qu'on a fait celui des galleries. Le bourg de Leuck, ou Loiche, est un des principaux endroits du Vallais, b�ti en pierres, dans une position fort �lev�e et tr�s-forte; l'art avoit encore ajout� anciennement � la force de son assiette, il y a encore d'anciens forts et des tours; toute cette hauteur est calcaire; on a la plus belle vue de ce lieu, elle s'�tend sur tout le bas Vallais jusqu'au dela de Martigny; nous avons donn� une foible id�e de cette vue, avant d'arriver aux bains de Loiche, car les expressions manquent pour rendre ces grands tableaux. Un spectacle bien int�ressant pour ceux qui �tudient les changemens qui arrivent journellement � la surface du globe, est la vue du Kolebesch, montagne fort �lev�e en face du bourg de Leuck, et de l'autre c�t� du Rh�ne; cette montagne est calcaire ainsi que la cha�ne sur la rive gauche du Rh�ne, du moins la partie avanc�e qui forme le vallon o� coule ce fleuve. Des chutes, des �boulemens y ont produit de grands changemens; les eaux et les torrens qui viennent des parties �lev�es, ont entra�n� ces d�bris, les ont d�pos�s aux pieds de la montagne, et en ont form� une colline qui a plus d'une demie-lieue jusqu'au Rh�ne, et plus d'une grande lieue de large, en forme circulaire; elle s'�tend vers le haut et le bas Vallais; la partie sup�rieure est couverte de pr�s et des p�turages; celle du c�t� du bas Vallais est couverte d'une for�t; elle va en pente douce; la grosseur des arbres prouve combien la formation de ce terrain est ancienne. Depuis la consolidation de ce terrain des torrens nouveaux y ont creus� un ravin large et profond, par lequel s'�coulent actuellement les eaux des montagnes, et les pierres qu'elles en arrachent. Le Rh�ne mine et emporte le pied de cette colline qui resserroit son cours, avec ces mat�riaux il va plus loin former des atterrissemens compos�s des mati�res les plus pesantes; les parties les plus fines le limon suspendu dans ces eaux servent ensuite � couvrir les anciens atterrissemens, au moyen desquels ils deviennent susceptibles de toute esp�ce de v�g�tation; ses eaux finissent de s'�purer dans le lac Leman, d'ou il sort clair et limpide, ainsi que toutes les rivieres qui sortent des lacs jusqu'� ce que d'autre torrens, tombant des montagnes, viennent les troubler de nouveau.�

Here is a most satisfactory view of the structure of this country on each side of the Rh�ne; strata of lime-stone and schisti, almost horizontal or little inclined, compose the mountains from their most lofty summits to the deepest bottom of those valleys. Such mountains cannot have been formed in any other manner than by the waste and degradation of their horizontal strata; consequently, here we are certain, that, from the summit of the Gemmi to those upon the other side of the Rh�ne, all the solid substance had been hollowed out by water. Thus were formed the valleys of the Rh�ne, the Dala, and a multitude of others.

M. de Saussure has given us a description of a tract of alpine country of the same kind with that of the Vallais now considered, so far as the strata are here in a horizontal position, instead of that highly inclined situation in which those primary bodies are commonly found. It is the description of Mount-Rosa Journal de Physique, Juillet 1790.

Here the same interesting observation may be made with regard to the immense destruction which must necessarily have taken place, in the elevated mass of solid earth, by the dissolving or wearing power of running water; and this will be clearly explained by the formation of those mountains and valleys, which, while they correspond with mountains and valleys in general, have something particular that distinguishes them from most of the Alps, where the strata, being much inclined, give occasion to form ranges of peaks disposed in lines according to the directions of the inclined strata. Here on the contrary, there being no general inclination of the strata to direct the formation of the peaks, they are found without any such order. I shall give it in M. de Saussure's own words.

�En effect toutes les hautes sommit�s que j'avois observ�es jusqu'� ce jour sont ou isol�es comme l'Etna, ou rang�es sur des lignes droites comme le Mont-Blanc et ses cimes collaterales. Mais l� je voyois le Mont Rose compos� d'une suite non-interrompue de pics gigantesques presqu'�gaux entr'eux, former un vaste cirque et renfermer dans leur enceinte, le village de Macugnaga, ses hameaux, ses p�turages, les glaciers qui les bordent, et les pentes escarp�es qui s'�l�vent jusqu'aux cimes de ces majestueux colosses.

�Mais ce n'est pas seulement la singularit� de cette forme qui rend cette montagne remarquable; c'est peut-�tre plus encore sa structure. J'ai constat� que le Mont-Blanc et tous les hauts sommets de sa cha�ne sont compos�s de couches verticales. Au Mont-Rose jusqu'aux cimes les plus �lev�es, tout est horizontal ou inclin� au plus de 30 degr�s.

�Enfin il se distingue encore par la mati�re dont il est construit. Il n'est point de granits en masse, comme le Mont-Blanc et les hautes c�mes qui l'entourent; ce sont des granits vein�s et des roches feuillet�es de diff�rens genre qui constituent la masse enti�re de cet assemblages de montagnes, depuis bases jusqu'� ses plus hautes cimes. Ce n'est pas que l'on n'y trouve du granit en masses, mais il y est purement accidentel, et sous la forme de rognons, de filons, ou de couches interpos�es entre celles des roches feuillet�es.

�On ne dira donc plus que les granits vein�s, le gneiss et les autres roches de ce genre, ne sont que les d�bris des granits rassembl�s et agglutin�s au pied des hautes montagnes, puisque voil� des roches de ce genre dont la hauteur �gale � tr�s-peu-pr�s celle des cimes granitiques les plus hautes connues, et ou l'on ferois bien embarrass� � trouver la place des montagnes de granit dont les d�bris out pu leur servir de mat�riaux; sur-tout si l'on consid�re la masse �norme de l'ensemble des murs d'un cirque tel que celui du Mont-Rose. En effet, ce seroit une hypoth�se inadmissible que de supposer, qu'anciennement il a exist� dans le vuide actuel du cirque une montagne de granit, et que ce cirque est le produit des d�bris de cette montagne. Car comment ne resteroit-il aucun vestige de cette montagne? On con�oit bien que sa t�te auroit pu se d�truire, mais son corps, la base du moins, prot�g�e par les d�bris de sa t�te accumul�s autour d'elle qu'est ce qui auroit pu l'an�antir; d'ailleurs les parois int�rieures du cirque quoique tr�s-escarp�es ne sont pourtant pas verticale; elles s'avancent de tous c�t�s vers l'int�rieur; et le fond, le milieu m�me du cirque n'est point du granit, il est de la m�me nature que ses bords. Enfin nous avons reconnu que les montagnes qui forment la couronne du Mont-Rose se prolongent au dehors � de grandes distances en sorte que leur ensemble forme une masse incomparablement plus grande que celle qui auroit rempli le vuide int�rieur du cirque.

�Il faut donc reconno�tre, comme tous les ph�nom�nes le d�montrent d'ailleurs, qu'il existe de montagnes de roches feuillet�es, compos�es des m�mes �l�mens que le granit, et qui sont sorties comme lui des mains de la nature sans avoir commenc� par �tres elles-m�mes des granits[22].�

[Footnote 22: M. de Saussure, upon the evidence before us, might have gone farther, and maintained that the masses of granite, which here traverse the strata in form of veins and irregular blocks, had been truly of a posterior formation. But this is a subject which we shall have afterwards to consider in a particular manner; and then this example must be recollected.]

Here is an example the most interesting that can be imagined. Those mountains are the highest in Europe, and their lofty peaks are altogether inaccessible upon one side. They had all been formed of the same horizontal strata. How then have they become separated peaks? And how have the valleys been hollowed out of this immense mass of elevated country?--No otherwise than as we may perceive it, upon every mountain, and after every flood. It is not often indeed, that, in those alpine regions, any considerable tract of country is to be found, where an example so convincing is exhibited. It is more common for those mountains of primary strata or schistus to rise up in ridges, which, though divided into great pyramids, may still be perceived as connected in the direction of their erected strata. These last, although affording the most satisfactory view of that mineral operation by which land, formed and consolidated at the bottom of the sea, had been elevated and displaced, are not so proper to inform us of the amazing waste of those extremely consolidated bodies, as are those where the strata have preserved their original horizontal portion. It is in this last case, that there are data remaining for calculating the minimum of the waste that must have been made of those mountains, by the regular and long continued operations of the atmospheric elements upon the surface of this earth.

It is the singularity of these horizontal strata in that extensive alpine mass, which seems to have engaged M. de Saussure, who has inspected so much of those instructive countries, to make a tour around those mountains, and to give us a particular description of this interesting place. Now, from this description, it is evident, that there is an immense mass of primary or alpine strata nearly in the horizontal position, which is common to all the strata at their original formation; that this horizontal mass had been raised into the highest place of land upon this globe; and that, in this high situation, it has suffered the greatest degradation, in being wasted by the hand of time, or operations of the elements employed in forming soil for plants, and procuring fertility for the use of animals. Here is nothing but a truth that may almost every where be perceived; but here that important truth is to be perceived on so great a scale, as to enable us to enlarge our ideas with regard to the natural operations of this earth, and to overcome those prejudices which contracted views of nature, and magnified opinions of the experience of man may have begotten,--prejudices that are apt to make us shut our eyes against the cleared light of reason.

Abundant more examples of this kind, were it necessary, might be given, both from this very good observator, and from M. de Luc[23].

[Footnote 23: Vid. Discours sur l'Histoire Naturelle de la Suisse, passim; but more particularly under the article of Route du Grindle wald � meiringen dans le pays de Hasti: Also Hist: de la Terre, Lettre 30. p. 45, et Lettre 31. page 68, etc.]

I will now only mention one from this last author, which we find in the Journal de Physique, Juin 1792.

�Entre Francfort et Hanau, le mein est bord� sur ses deux rives, de collines dans lesquelles la lave se trouve ench�ss�e entre des couches calcaires. Ces couches sont tr�s-remarquables par leur contenue, qui est le m�me au-dessus et au-dessous de la lave, et qu'on retrouve dans les couches d'une grande �tendue de pays, ou, comme d'ordinaire, on voit leurs sections abruptes dans les flancs de collines, mais sans lave, except� dans le lieu indiqu�.�

The particular structure of those lime-stone strata, with the body of basaltes or subterraneous lava which is interposed among them, shows evidently the former connection of those two banks of the river, by solid matter, the same as that which we see left there, and in the flanks of those hills. That which is wanting, therefore, of those stratified masses, in that great extent of country, marks out to us the minimum of what has been lost, in having been worn by the attrition of travelled materials.

I would now beg leave, for a moment, to transport my reader to the other side of the Atlantic, in order to perceive if the same system of rivers wearing mountains is to be found in that new world, as we have found it in the old.

Of all the mountains upon the earth, so far as we are informed by our maps, none seem to be so regularly disposed as are the ridges of the Virginian mountains. There is in that country a rectilinear continuity of mountains, and a parallelism among the ridges, no where else to be observed, at least not in such a great degree.

At neither end of those parallel ridges is there a direct conveyance for the waters to the sea. At the south end, the Allegany ridge runs across the other parallel ridges, and shuts up the passage of the water in that direction. On the north, again, the parallel ridges terminate in great irregularity. The water therefore, that is collected from the parallel valley, is gathered into two great rivers, which break through those ridges, no doubt at the most convenient places, forming two great gapes in the blue ridge, which is the most easterly of those parallel ridges.

Now, so far as mountains are in the original constitution of a country, the ridges of those mountains must have been a directing cause to the rivers. But so far as rivers, in their course from the higher to the lower country, move bodies with the force of their rolling waters, and wear away the solid strata of the earth, we must consider rivers as also forming mountains, at least as forming the valleys which are co-relative in what is termed mountain. Nothing is more evident than the operation of those two causes in this mountainous country of Virginia; the original ridges of mountains, or indurated and elevated land, have directed the courses of the rivers, and the running of those rivers have modified the mountains from whence their origin is taken. I have often admired, in the map, that wonderful regularity with which those mountains are laid down, and I have much wished for a sight of that gap, through which the rivers, gathered in the long valleys of those mountains, break through the ridge and find a passage to the sea. A description of this gap we have by Mr Jefferson, in his notes on Virginia.

�The passage of the Potomac, through the Blue Ridge, is perhaps one of the most stupendous scenes in nature. You stand on a very high point of land. On your right comes up the Shenandoah, having ranged, along the foot of the mountains, an hundred miles to seek a vent. On the left approaches the Potomac, in quest of a passage also. In the moment of their junction, they rush together against the mountain, rend it asunder, and pass off to the sea.

�The first glance of this scene hurries our senses into the opinion, that this earth had been erected in time; that the mountains were formed first; that the rivers began to flow afterwards; that in this place particularly they have been dammed up by the Blue Ridge of mountains, and have formed an ocean which filled the whole valley; that, continuing to rise, they have at length broken over this spot, and have torn the mountain down from its summit to its base. The piles of rock on each hand, but particularly on the Shenandoah, the evident marks of this disrupture and avulsion from their beds, by the most powerful agents of nature, corroborate the impression. But the distant finishing which nature has given to the picture is of a different character. It is a true contrast to the foreground. It is as placid and delightful as that is wild and tremendous. For the mountain being cloven asunder, she presents to your eye, through the cleft, a small catch of smooth blue horizon at an infinite distance in the plain country, inviting you, as it were, from the riot and tumult roaring around, to pass through the breach, and partake of the calm below. Here the eye ultimately composes itself; and that way too the road happens actually to lead. You cross the Potomac above the junction, pass along its side through the base of the mountain for three miles, its terrible precipices hanging in fragments over you, and within about twenty miles reach of Frederick town, and the fine country around it. This scene is worth a voyage across the Atlantic. Yet here, as in the neighbourhood of the natural bridge, are people who have passed their lives within half a dozen of miles, and have never been to survey these monuments of a war between the rivers and mountains, which must have shaken the earth itself to its center.�

To this description of the passage of the Potomac may be added what Mr Jefferson, in the appendix, has given from his friend Mr Thomson, secretary of Congress.

�The reflections I was led into on viewing this passage of the Potomac through the Blue Ridge were, that this country must have suffered some violent convulsion, and that the face of it must have been changed from what it probably was some centuries ago; that broken and ragged faces of the mountain on each side of the river; the tremendous rocks which are left with one end fixed in the precipice, and the other jutting out, and seemingly ready to fall for want of support; the bed of the river for several miles below obstructed, and filled with the loose stones carried from this mound; in short, every thing on which you cast your eye evidently demonstrates a disrupture and breach in the mountain, and that before this happened, what is now a fruitful vale, was formerly a great lake, or collection of water, which possibly might have here formed a mighty cascade, or had its vent to the ocean by the Susquehanna, where the Blue Ridge seems to terminate. Besides this, there are other parts of this country which bear evident traces of a like convulsion. From the best accounts I have been able to obtain, the place where the Delaware now flows through the Kittatinny mountain, which is a continuation of what is called the North Ridge, or mountain, was not its original course, but that it passed through what is now called the Wind-gap, a place several miles to the westward, and above an hundred feet higher than the present bed of the river. This Wind-gap is about a mile broad, and the stones in it such as seem to have been washed for ages by water running over them. Should this have been the case, there must have been a lake behind that mountain; and, by some uncommon swell in the waters, or by some convulsion of nature, the river must have opened its way through a different part of the mountain, and meeting there with less obstruction, carried away with it the opposing mounds of earth, and deluged the country below with the immense collection of waters to which this new passage gave vent. There are still remaining, and daily discovered, innumerable instances of such a deluge on both sides of the river, after it passed the hills above the falls of Trenton, and reached the champaign. On the New Jersey side, which is flatter than the Pennsylvania side, all the country below Croswick hills seems to have been overflowed to the distance of from ten to fifteen miles back from the river, and to have acquired a new soil, by the earth and clay brought down and mixed with the native sand. The spot on which Philadelphia stands evidently appears to be made ground. The different strata through which they pass in digging for water, the acorns, leaves, and sometimes branches which are found above twenty feet below the surface, all seem to demonstrate this.�

How little reason there is to ascribe to extraordinary convulsions the excavations which are made by water upon the surface of the earth, will appear most evidently from the examination of that natural bridge of which mention is made above, and which is situated in the same ridge of mountains, far to the south, upon a branch of James's River. Mr Jefferson gives the following account of it.

"The natural bridge, the most sublime of nature's works, is on the ascent of a hill, which seems to have been cloven through its length by some great convulsion. The fissure, just at the bridge, is by some admeasurements 270 feet deep, by others 205; it is about 45 feet wide at the bottom, and 90 feet at the top; this of course determines the length of the bridge, and its height from the water. Its breadth in the middle is about 60 feet, but more at the ends; and the thickness of the mass at the summit of the arch about 40 feet. A part of its thickness is constituted by a coat of earth, which gives growth to many large trees. The residue, with the hill on both sides, is one solid rock of lime-stone. The arch approaches the semi-elliptical form; but the larger axis of the ellipsis, which would be the cord of the arch, is many times longer than the transverse. Though the sides of the bridge are provided in some parts with a parapet of fixed rock, yet few men have resolution to walk to them, and look over into the abyss. You involuntarily fall on your hands and feet, and creep to the parapet, and look over it. Looking down from this height about a minute gave me a violent headache. If the view from the top be painful and intolerable, that from below is delightful in the extreme. It is impossible for the emotions arising from the sublime to be felt beyond what they are here. On the sight of so beautiful an arch, so elevated, so light, and springing as it were up to heaven, the rapture of the spectator is really indescribable! The fissure, continuing narrow, deep, and straight, for a considerable distance above and below the bridge, opens a short but very pleasing view of the north mountain on one side, and blue ridge on the other, at the distance each of them of about five miles. This bridge is in the county of Rockbridge, to which it has given name, and affords a public and commodious passage over a valley, which cannot be crossed elsewhere for a considerable distance. The stream passing under it is called Cedar Creek: it is a water of James's River, and sufficient in the driest seasons to turn a grist mill, though its fountain is not more than two miles above[24]."

[Footnote 24: Upon this occasion it may be observed, the most wonderful thing, with regard to cosmology, is that such remnants, forming bridges, are so rare; this therefore must be an extraordinary piece of solid rock, or some very peculiar circumstances must have concurred to preserve this monument of the former situation of things.]

Thus both in what is called the Old World and the New, we shall be astonished in looking into the operations of time employing water to move the solid masses from their places, and to change the face of nature, on the earth, without defacing nature. At all times there is a terraqueous globe, for the use of plants and animals; at all times there is upon the surface of the earth dry land and moving water, although the particular shape and situation of those things fluctuate, and are not permanent as are the laws of nature.

It is therefore most reasonable, from what appears, to conclude, that the tops of the mountains have been in time past much degraded by the decay of rocks, or by the natural operations of the elements upon the surface of the earth; that the present mountains are parts which either from their situation had been less exposed to those injuries of what is called time, or from the solidity of their constitution have been able to resist them better; and that the present valleys, or hollows between the mountains, have been formed in wasting the rock and in washing away the soil.

If this is the case, that rivers have every where run upon higher levels than those in which we find them flowing at the present, there must be every where to an observing eye marks left upon the sides of rivers, by which it may be judged if this conclusion be true. I shall now transcribe a description of a part of the Vallais by which this will appear. (Discours sur l'Histoire Naturelle de la Suisse.)

�Apr�s avoir pass� le village de Saint-Leonard, on commence � monter la montagne de la Plati�re; cette route est on ne peut plus int�ressante pour le naturaliste Etc.

�On se trouve fort �lev� au-dessus du Rh�ne quand on est sur le haut de ce chemin, dont on d�couvre un de plus singuliers, des plus riches, et de plus vari�s passages qu'on puisse imaginer. On voit sous ses pieds le Rh�ne serpenter dans le lit qu'il se creuse actuellement, car il change et tout prouve qu'il en a souvent chang�; une quantit� prodigieuse de petites isles le s�parent et le coupent en une multitude de canaux et de bras; ces isles sont couvertes les unes d'arbres, d'arbustes, de p�turages, de bosquets et de verdure, d'autres de pierres, de sable, et de d�bris de rochers; quelques-unes sont form�es ou occasionn�es par un amas de troncs d'arbres entass�s avec de grands sapins renvers�s dont les long tiges h�riss�es de branches droites et nues repr�sentent des chevaux de frise, et donnent l'id�e de ces abatis destin�s � preserver un pays contre l'approche de l'ennemi. Du c�t� du bas Vallais, on suit � perte de vue le fleuve dans ses sinuosit�s et ses d�tours, on l'apper�oit �galement dans le haut Vallais; des avances de montagne le cachent quelquefois: il reparo�t et diminue insensiblement en approchant de ces monts �lev�s ou il prend sa source: le fond du vallon paro�t �tre de niveau, s'abaisser seulement d'une pente douce du c�t� du bas Vallais: des mamelons, des hauteurs des monticules isol�s, quelquefois group�s de diff�rentes manieres, sont r�pandus dans cet espace, et rappellent la vue d'une pr� d�vast� par les taupes; plusieurs de ces hauteurs sont surmont�es des ruines d'antiques ch�teaux, d'eglises, et de chapelles; des villages distribu�s �a et l� enrichissent ce fond, qui d'ailleurs est couvert de p�turages, de champs d'arbres, de bois, et de bosquets; les enclos des possessions le coupent en mille figure bizarres et irr�guli�res. Ces monticules avec leurs fabriques s'�l�vent au-dessus de tous ces objets vari�s; quelques-unes se distinguent par leur c�t�s �croul�s qui sont � pic; la blancheur de ces �boulemens contraste singuli�rement avec les verts qui sont les couleurs dominantes du vallon. Au-de-la des coteaux, des montagnes s'�l�vent et vont s'appuyer et s'adosser � ces masses, � ces colosses �normes de rochers � pic �lev�s comme des murailles et d'une hauteur prodigieuse qui forment cette barri�re qui s�pare le Vallais de la Savoie. Les contours du pied de ces monts forment des entr�es de vallons et de vall�es d'ou descendent et se pr�cipitent des torrens qui viennent grossir les eaux du Rh�ne; la vue cherche � p�n�trer et � s'�tendre dans ces espaces, l'imagination cherche vainement des passages dans effrayantes limites, parmi ces �cueils et ces rochers amoncel�s, elle est arr�t�e partout; de noires for�ts de sapin sont suspendues parmi ces rochers blancs-jaun�tres, qui se terminent enfin par une multitude d'aiguilles et de pyramides qu'on voit percer au travers des neiges et des glaces, s'�lancer dans les nues, s'y cacher et s'y perdre.

�En examinant de plus pr�s ces mamelons r�pandus dans le vallon, on voit qu'ils sont compos�s de pierres, de sables, et de d�bris rapport�s et amoncel�s sans ordre depuis des temps dont rien ne peut fixer l'�poque: on voit que les eaux du Rh�ne ont coul� � leurs pied, qu'il en a min� plusieurs et a occasionn� leurs chutes et leurs ruines. On voit actuellement quelques mamelons qui subissent ces m�mes d�gradations, et fournissent au Rh�ne les mat�riaux dont il va former plus loin ces atterissemens dont nous avons parl�. La confusion et le d�sordre qui se remarque dans la composition int�rieure de ces mamelons prouvent qu'ils ne sont pas le produit de la mer ou des eaux qui ont travaill� successivement et lentement � la formation de la plupart des terrains; mais que le fond de ce vallon a �t� rempli des d�combres et des d�bris des montagnes sup�rieures, qu'ils y ont �t� entra�n�s par des inondations et des d�bordemens subits; que les eaux du Rh�ne ensuite ont parcouru ce vallon qu'il a souvent chang� de lit; que c'est en tournant et en circulant dans ce terrain nouvellement form�, qu'il a creus� les espaces qui sont entre ces mamelons, et que c'est en creusant le terrain qu'ils se sont �lev�s; leurs formes et leurs pentes allong�es vers le bas Vallais, sont de nouvelles preuves que ce sont les eaux actuelles qui ont chang� la surface de ce terrain, nous verrons de nouvelles preuves de ce que nous disons en avan�ant d'avantage vers le haut Vallais; il n'y a peut-�tre point d'endroit plus propre � �tudier le travail des eaux que ce vallon qu'on a la facilit� de voir et d'examiner sous des aspects diff�rentes.�

Another example of the same kind, with regard to the bed of the Rhine, we have from the same author. (Discours, etc. page 259.)

�De Richenau � Coire, Troyen, et Saint-Gal.

�Pour aller � Coire on passe le port qui est sur le haut Rhin; en c�toyant ce fleuve, qui coule dans un fond, on entre dans une plaine de niveau, qui n'a qu'une pente tr�s insensible de trois quarts de lieue; le fond du terrain n'est qu'un amas de pierres roul�es de toutes esp�ces. Les deux c�t�s sont bord�s de montagnes calcaire qui courent parall�lement entr'elles. Celle de la gauche, au pied de laquelle coule le Rhine, est tr�s rapide et perpendiculaire � son sommet; celle qui est � droite de la plaine ou petit vallon, puisqu'il se trouve entre des montagnes, est moins haute, plus bois�e, et couverte de sapins. Le vallon est aussi couvert, en partie, de tr�s-grands et beaux pins; mais ce qu'on y voit de plus remarquable, c'est une douzaine de gros mamelons ou butes, �lev�es de cinquante � soixante toises, plus ou moins isol�e, et � diff�rentes distances les unes des autres; ces butes sont rondes, la plupart allong�es dans le sens du vallon, et compos�es de d�bris calcaires et de sables; le fond du vallon est m�l� de plus d'esp�ces de galets. On ne croit pas se tromper en disant que ce vallon a �t� rempli de mati�res apport�es par les eaux jusqu'� la hauteur ou sont encore actuellement les mamelons; que de nouvelles inondations ont ensuite creus� et entra�n� ce qui manque de terrain � ces mamelons; que c'est en circulant autour de ces mamelons que les eaux leur ont donn� la forme ronde; et surtout allong�e dans le sens du vallon, et que c'est par le moyen de ces m�mes eaux que le fond actuel de cette plaine a pris ce niveau et cette pente insensible vers un pays plus ouvert qui est au-dela. On a d�j� fait mention de pareils mamelons qui se trouvent dans le vallon du Vallais parcouru par le Rh�ne.�

These examples may also be supported by what this author observes in another place[25].

[Footnote 25: Discours, etc. page 201.]

�Le vallon o� est situ� Meiringen, est visiblement form� par le d�p�t des eaux, il est de niveau, et s'�tend trois lieues en longueur jusqu'au lac de Brientz, � la suite duquel est le m�me terrain nivel�, qui va jusqu'au lac de Thun, dont on a parl�. Une autre observation qui concourt � favoriser ce sentiment, c'est que toutes les roches calcaires, qui entourent le vallon, sont � pic, qu'on y remarque des cavit�s circulaires et des enfoncemens � m�me hauteur et � diff�rents points, qui constatent la fouille et le mouvement des eaux contre ces parois.�

Thus we have seen the operation of the atmospheric elements degrading mountains, and hollowing out the valleys of this earth.

The land which comes from the mineral region in a consolidated state, in order to endure the injuries of those atmospheric elements, must be resolved in time for the purposes of fertilising the surface of this earth. In no station whatever is it to be exempted from the wasting operations, which are equally necessary, in the system of this world, as were those by which it had been produced. But with what wisdom is that destroying power disposed! The summit of the mountain is degraded, and the materials of this part, which in a manner has become useless from its excessive height, are employed in order to extend the limits of the shore, and thus increase the useful basis of our dwellings. It is our business to trace this operation through all the intermediate steps of that progress, and thus to understand what we see upon the surface of this earth, by knowing the principles upon which the system of this world proceeds.

The valley of the Rh�ne is continued up to the mountain of St. Gothard, which may be considered as the centre of the Continent, since, from the different sides of this mountain, the water runs in all directions. To the German Sea it runs by the Rhine, to the Mediterranean by the Rhone, and to the Adriatic by the Po. Here it may be proper to take a general view of this mountainous country, or that great mass of rock or solid strata which has been either formed originally in its present shape, or has been excavated by the constant operation of water running from the summit in all the different directions.

On the one hand, it is supposed that the forming cause which had produced those mountains, in collecting their materials at the bottom of the sea, had also determined the shape in which their various ridges are at present found; on the other hand, it is supposed that the destructive causes, which operate in degrading mountains, have immediately contributed to produce their present forms, and that it is only mediately or more remotely that this shape has been determined by mineral operations and the constitution of the solid parts, which thus oppose the wearing operations of the surface with different degrees of hardness and solidity. Whether natural appearances correspond with the one or the other of those two different suppositions, every person who has the opportunity of making such an examination, and has sufficient knowledge of the subject to judge from his observation, will determine for himself.

I will here give the opinion of a person who has had great opportunities for this purpose, who is an intelligent as well as an attentive observator, and who has had particularly this question in his view. It is from 'Tableaux de la Suisse'[26].

[Footnote 26: �Discours sur l'Histoire Naturelle de la Suisse.�]

�Quand nous nous sommes trouv� sur ces points �lev�s, nous avons toujours consid�r� le total des montagnes prises ensemble, leurs situations respectives, les unes par rapport aux autres; afin de reconno�tre, s'il y avoit quelque chose de constant dans leurs position; rien n'est plus vari�. Dans la grande cha�ne de montagnes qui s�pare le canton de Berne du Vallais d'un c�t�, et les Alpes qui s�parent le Vallais de la Savoie de l'autre, en consid�rant le course du Rh�ne sous differens points de vue, on n'a point vu que les angles saillans de ces tr�s hautes montagnes fussent oppos�s aux angles rentrans des montagnes qui sont vis-�-vis; Le fameux vallon qui est sur le haut du Saint-Gothard, le point le plus �lev� de l'Europe, contredit �galement cette observation, aussi que les positions de la plus grande partie des montagnes qui forment son vaste circuit. Le vallon de Scholenen, qui a plus de huit lieues, et dans lequel la Reusse coule du sommet du Saint-Gothard jusqu'au lac de Lucerne, offre � peine quelques exemples d'angles rentrans oppos�s � des angles saillans. Les nombreux vallons que nous avons constamment travers�s ceux qui conduisent au Grindelwald, et celui qui m�ne au pays de Hasli qui sont sous nos yeux, n'�tablirent pas d'avantage cette correspondance d'angles saillans et angles rentrans, qu'on regarde comme si constante. Dans les montagnes basses, du troisi�me et quatri�me ordre, ou inf�rieures, on remarque plus souvent cette correspondance, encore n'est-elle pas constante: les eaux ordinaires ont form� ces vallons; mais si on veut donner une th�orie g�n�rale, c'est assurement dans les plus hautes montagnes qu'il faut prendre ses exemples. Ce qui se trouve au-dessous de ces points les plus �lev�s, a pris sa forme de la disposition m�me des plus hauts sommets.�

M. de Saussure, in his second volume of Voyages dans les Alpes, gives the strongest confirmation to the theory of the gradual degradation of mountains by the means of rain.

�� 920. Je reviens aux observations. Il en est une tr�s importante pour la th�orie de la terre, dont on peut du haut du Cramont appr�cier la valeur, mieux que d'aucun autre site; je veux parler de la fameuse observation de Bourguet sur la correspondance des angles saillans avec les angles rentrans des vall�es. J'ai a d�j� dit un mot dans le 1er. volume, � 577, mais j'ai renvoy� � ce chapitre les developpemens que je vais donner.

�Ce qui avoit fait regarder cette observation comme tr�s-importante, c'est que l'on avoit cru qu'elle pourroit servir � d�montrer que les vall�es ont �t� creus�es par des courans de la mer, dans le temps o� elle couvroit encore les montagnes; ou que les montagnes qui bordent ces vall�es avoient �t� elles-m�mes form�es par l'accumulation des d�p�ts rejet�s sur les bords de ces m�mes courans.

�Mais l'inspection des vall�es que l'on d�couvre du haut du Cramont d�montre pleinement le peu de solidit� de ces deux suppositions. En effet, toutes les vall�es que l'on d�couvre du haut de cette cime sont ferm�es, au moins � l'une de leurs extr�mit�s et quelques-unes � leurs deux extr�mit�s, par des cols �lev�s, ou m�me par des montagnes d'une tr�s-grande hauteur: toutes sont coup�es � angles droits par d'autres vall�es, et l'on voit enfin clairement que la plupart d'entr'elles ont �t� creus�es, non point dans la mer, mais, ou au moment de sa retraite, ou depuis sa retraite, par les eaux des neiges et des pluies.

�On a d'abord sous ses yeux la grande vall�e de l'All�e-Blanche, qui �tant parall�le � la direction g�n�ral de cette partie des Alpes, est du nombre de celles que je nomme longitudinales; et l'on voit cette vall�e barr�e � l'une de ses extr�mit�s par le Col de la Seigne et � l'autre par le Col Ferret. En se retournant du c�t� de l'Italie, on voit plusieurs vall�es �-peu-pr�s parall�les � celle-l�, comme celle de la Tuile, celle du Grand Saint Bernard, qui toutes aboutissent, par le haut, � quelque Col tr�s-�lev�, et par le bas, � la Doire, o� elles viennent se jeter vis-�-vis de quelque montagne qui leur correspond de l'autre c�t� de cette vall�e.

�Si l'on consid�re ensuite cette m�me vall�e de la Doire, qui descend de Courmayeur � Yvr�e, on la verra barr�e par le Mont-Blanc et par la cha�ne centrale, qui la coupent � angles droits dans la partie sup�rieure. On verra cette m�me vall�e s'ouvrir, dans un espace de sept ou huit lieues, deux ou trois inflexions tout-�-fait brusques; et on la verra enfin coup�e � angles droits par une quantit� de vall�es qui viennent y verser leurs eaux, et qui sont elles m�mes coup�es par d'autres, dont elles re�oivent aussi le tribut. Or quand on r�fl�chit � la largeur et � l'�tendue des courans de la mer, peut-on concevoir que ces sillons �troits, barr�s, qui se coupent en �chiquier � de tr�s-petites distances, aient pu �tre creus�s par de semblables courans.

�L'observation de la correspondance des angles, fut-elle aussi universelle qu'elle l'est peu, ne prouveroit donc autre chose, sinon que les vall�es sont n�es de la fissure et de l'�cartement des montagnes, ou qu'elles ont �t� creus�es par les torrens et les rivi�res qui y coulent actuellement. On voit un grand nombre de vall�es na�tre, comme je l'ai fait voir au Bon-Homme, � 767, sur les flancs d'une montagne; on les voit s'�largir et s'approfondir a proportion des eaux qui y coulent; un ruisseau qui sort d'une glacier, ou qui sort d'une prairie, creuse un sillon, petit d'abord, mais qui s'agrandit successivement � mesure que ses eaux grossissent, par la r�union d'autres sources ou d'autres torrens.

�Il n'est m�me pas n�cessaire, pour se convaincre de la v�rit� da ces faits, de gravir sur le Cramont. Il suffit de jeter les yeux sur la premiere carte que l'on trouvera sous la main, des Pyr�n�es, de l'Apennin, des Alpes, ou de quelqu'autre cha�ne de montagnes que ce puisse �tre. On y verra toutes les vall�es indiqu�es par le cours des rivieres; on verra ces rivieres et les vall�es dans lesquelles elles coulent, aboutir par une de leurs extr�mit�s au sommet de quelque montagne ou de quelque col �lev�. Les replis tortueux d'un grand fleuve, indiqueront une vall�e principale, dans laquelle des torrens ou des rivieres qui indiquent d'autres vall�es moins consid�rables, viennent aboutir, sous des angles plus ou moins approchans de l'angle droit. Or ces rivieres qui viennent de droite et de gauche se jeter dans la vall�e principale, ne s'accordent pas pour se jeter par paires dans le m�me point du fleuve; elles sont comme les branches d'un arbre qui s'implantent alternativement sur son tronc, et par cons�quent, chaque petite vall�e se jette dans la vall�e principale vis-�-vis d'une montagne. Et de plus on verra aussi sur les cartes que m�me les plus grandes vall�es ont presque toutes des �tranglemens qui forment des �cluses, des fourches, des d�fil�s.

�Je ne pr�tends cependant pas que l'�rosion des eaux pluviales, des torrens et des rivieres, soit l'unique cause de la formation des vall�es: le redressement des couches des montagnes nous force � en admettre une autre, dont je parlerai ailleurs; j'ai voulu seulement prouver, ici que la correspondance des angles, lorsqu'elle a lieu dans les vall�es, ne prouve point que ces vall�es soient l'ouvrage des courans de la mer.�

The place to which M. de Saussure here remits us is where he afterwards, in describing the Val d'Aoste, makes the following observation.

�(� 960.) Au-dela de Nuz, les montagnes qui bordent au midi la vall�e, et dont on voit d'ici tr�s-bien la structure, sont compos�es de grandes couches appliqu�es les unes contre les autres, et termin�es par des cimes aigues, escarp�es contre le midi, elles tournent ainsi le dos � la vall�e, dont la direction est toujours � 10 degr�s de l'est par nord. Celles de la gauche que nous c�toyons, et qui sont de nature schisteuse, tournent aussi le dos � la vall�e en s'�levant contre le nord. Je crois pouvoir conclure de l�, que cette vall�e est une de celles dont la formation tient � celle des montagnes m�mes, et non point � l'�rosion des courans de la mer ou des rivi�res. Les vall�es de ce genre, paroissent avoir �t� form�es par un affaissement partiel des couches des montagnes, qui ont consenti, dans la direction qu'ont actuellement ces vall�es.�

Here I would beg leave to differ a little from this opinion of M. de Saussure, at least from the manner in which it is expressed; for perhaps at bottom our opinions upon this subject do not differ much.

M. de Saussure says that the formation of this valley depends upon the mountains themselves, and not upon the erosion of the rivers. I agree with our author, so far as the mountains may have here determined the shape and situation of the valley; but, so far as this valley was hollowed out of the solid mass of our earth, there cannot be the least doubt that the proper agent was the running water of the rivers. The question, therefore, comes to this, How far it is reasonable to conclude that this valley had been hollowed out of the solid mass. Now, according to the present theory, where the strata consolidated at the bottom of the sea are supposed to be erected into the place of land, we cannot suppose any valley formed by another agent than the running water upon the surface, although the parts which are first to be washed away, and those which are to remain longest, must be determined by a concurrence of various circumstances, among which this converging declivity of the strata in the bordering mountains, doubtless, must be enumerated.

With regard to any other theory which shall better explain the present shape of the surface of the earth, by giving a cause for the changed position of the strata originally horizontal, I cannot form a judgment, as I do not understand by what means strata, which were formed horizontally, should have been afterwards inclined, unless it be that of a power acting under those strata, and first erecting them in relation to the solid globe on which they rested.

Besides, in supposing this valley original, and not formed by the erosion of the rivers, What effect should we ascribe to the transport of all those materials of the Alps, which it is demonstrable must have travelled through this valley? Whether is it more reasonable to suppose, on the one hand, that the action and attrition of all the hard materials, running for millions of ages between those two mountains, had hollowed out that mass which originally intervened; or, on the other, that this valley had been originally formed in its present shape, while thousands of other valleys have been hollowed out of the solid mass?

But to put this question out of doubt, with regard to this very valley of the river Doire, M de Saussure has given us the following decisive fact, � 881: �Imm�diatement au-dessus de cette source, est un rocher qui r�pond si pr�cis�ment � un autre rocher de la m�me nature, situ� de l'autre c�t� de la vall�e de Courmayeur, qu'on ne sauroit douter qu'ils n'aient �t� anciennement unis par une montagne interm�diaire, d�truite par les ravages du temps.�

Now, to see how little the situation of the strata influences the shape of the valleys, I shall transcribe the two paragraphs immediately following that which has given occasion to the present discussion.

�Un peu au-dela de Nux, la vall�e cesse d'�tre large et plane, comme elle �toit dans le environs de la cit�; elle devient �troite et tr�s vari�e; l� st�rile et sauvage, ici couverte de vergers et de prairies arros�es par la Doire.

�� 961. Les couches des montagnes � notre gauche, qui depuis la cit� avoient constamment couru � l'est et mont� au nord, paroissent changer � un quart de lieue du village de Chambaise, qui est � une lieue et un quart de Nux. Elles montent d'abord au sud-est, et peu plus loin droit au sud, tandis que l'autre c�t� de la vall�e elles paroissent monter � l'est.�

In every mountain, and in every valley, the solid parts below have contributed in some manner to determine the shape of the surface of the earth; but in no place is the original shape of the earth, such as it had first appeared above the sea, to be found. Every part of the land is wasted; even the tops of the mountains, over which no floods of water run, are degraded. But this wasting operation, which affects the solid rock upon the summit of the mountain, operates slowly in some places, compared with that which may be observed in others. Now, it is in the valleys that this operation is so perceptible; and it is in the valley that there is such a quick succession of things as must strike the mind of any diligent observer; but this is the reason why we must conclude, that at least all the valleys are the operation of running water in the course of time. If this is granted, we have but to consider the mountains as formed by the hollowing out of the valleys, and the valleys as hollowed out by the attrition of hard materials coming from the mountains. Here is the explanation of the general appearance of mountain and valley, of hill and dale, of height and hollow; while each particular shape must have its dependence, consequently its explanation, upon some local circumstance.

But, besides the general conformation of mountains and valleys, there may be also, in the forms of mountains, certain characters depending upon the species of substances or rocks of which they are composed, and the general manner in which those masses are wasted by the operations of the surface. Thus there is some character in the external appearance of a hill, a mountain, or a ridge of hills and mountains; but this appearance is generally attended with various circumstances, or is so complicated in its nature, as to be always difficult to read; and it is but seldom that it affords any very particular information; although, after knowing all the state and circumstances of the case, I have always found the appearances most intelligible, and strictly corresponding with the general principle of atmospheric influence acting upon the particular structure of the earth below.

M. de Saussure has given us an observation of this kind, in describing the mountains through which the Rh�ne has made its way out of the Alps, at the bottom of the Vall�e.

��. 1061. Plus loin le village de Juviana ou Envionne on voit des rochers qui ont une forme que je nomme moutonn�e; car on est tent� de donner des noms � des modifications qui n'en ont pas, et qui ont pourtant un caract�re propre. Les montagnes que je d�signe par cette expression sont compos�es d'un assemblage de t�tes arrondies, couvertes quelquefois de bois, mais plus souvent d'herbes, ou tout au plus de brousailles. Ces rondeurs contigu�s et r�p�t�es forment en grand l'effet d'une toison bien fournie, ou de ces perruques que l'on nomm� aussi moutonn�es. Les montagnes qui se pr�sentent sous cette forme, sont presque toujours de rochers primitives, ou au moins des st�atites; car je n'ai jamais vu aucune montagne de pierre � chaux ou d'ardoise rev�tir cette apparence. Les signes qui peuvent donner quelque indice de la nature des montagnes, � de grandes distances et au travers des plantes qui le couvrent, sont en petit nombre, et m�ritent d'�tre �tudi�s et consacr�s par des termes propres.�

When philosophers propose vague theories of the earth, theories which contain no principle for investigating either the general disorder of strata or the particular form of mountains, such theories can receive no confirmation from the examination of the earth, nor can they afford any rule by which the phenomena in question might be explained. This is not the case when a theory presents both the efficient and final cause of those disorders in bodies which had been originally formed regular, and which shows the use as well as means for the formation of our mountains. Here illustration and confirmation of the theory may be found in the examination of nature; and natural appearances may receive that explanation which the generalization of a proper theory affords.

The particular forms of mountains depend upon the compound operation of two very different causes. One of these consists in those mineral operations by which the strata of the earth are consolidated and displaced, or disordered in the production of land above the sea; the other again consists in those meteorological operations by which this earth is rendered a habitable world. In the one operation, loose materials are united, for the purpose of resisting the dissolving powers which act upon the surface of the earth; in the other, consolidated masses are again dissolved, for the purpose of serving vegetation and entertaining animal life. But, in fulfilling those purposes of a habitable earth, or serving that great end, the land above the level of the sea is wasted, and the materials are transported to the bottom of the ocean from whence that consolidated land had come. At present we only want to see the cause of those particular shapes which are found among the most elevated places of our earth, those places upon which the wasting powers of the surface act with greatest energy or force.

In explaining those appearances of degraded mountains variously shaped, the fact we are now to reason upon is this; first, that in the consolidated earth we find great inequality in the resisting powers of the various consolidated bodies, both from the different degrees of consolidation which had taken place among them, and the different degrees of solubility which is found in the consolidated substances; and, secondly, that we find great diversity in the size, form, and positions of those most durable bodies which, by resisting longer the effects of the wearing operations of the surface, must determine the shape of the remaining mass. Now so far as every particular shape upon the surface of this earth is found to correspond to the effect of those two causes, the theory which gave those principles must be confirmed in the examination of the earth; and so far as the theory is admitted to be just, we have principles for the explanation of every appearance of that kind, whether from the forming or destroying operations of this earth, there being no part upon the surface of this earth in which the effect of both those causes must not more or less appear.

But though the effects of those two causes be evident in the conformation of every mountainous region, it is not always easy to analyse those effects so as to see the efficient cause. Without sections of mountains their internal structure cannot be perceived, if the surface which we see be covered with soil as is generally the case. It is true, indeed, that the solid bodies often partially appear through that covering of soil, and so far discover to us what is to be found within; but as those solid parts are often in disorder, we cannot, from a small portion, always judge of the generality. Besides, the solid parts of mountains is often a compound thing, composed both of stratified and injected bodies; it is therefore most precarious, from a portion which is seen, to form a judgment of a whole mass which is unexplored. Nevertheless, knowing the principles observed by nature both in the construction and degradation of mountains, and cautiously inferring nothing farther than the data will admit of, some conclusion may be formed, in reasoning from what is known to what is still unknown.

It is with this view that we are now to consider the general forms of mountains, such as they appear to us at a certain distance, when we have not the opportunity of examining them in a more perfect manner. For, though we may not thus learn always to understand that which is thus examined, we shall learn, what is still more interesting, viz. that those mountains have been formed in the natural operations of the earth, and according to physical rules that may be investigated.

We are to distinguish mountains as being either on the one hand soft and smooth, or on the other hand as hard and rocky. If we can understand those two great divisions by themselves, we shall find it easy to explain the more complex cases, where these two general appearances partially prevail. Let us therefore examine this general division which we have made with regard to the external character of mountains.

The soft and smooth mountains are generally formed of the schisti, when there is any considerable extent of such alpine or mountainous region. The substance is sufficiently durable to form a mountain, or sufficiently strong, in its natural state, to resist the greatest torrent of water; at the same time this fissible substance generally decays so completely, when exposed to the atmosphere, as to leave no salient rock exposed by which to characterise the mountain.

Of this kind are the schisti of Wales, of Cumberland, of the isle of Man, and of the south of Scotland. I do not say absolutely, that there is no other kind of material, besides the schisti which gives this species of mountain, but only that this is generally the case in alpine situations. It may be also formed of any other substance which has solidity enough to remain in the form of mountains, and at same time not enough to form salient rocks. Such, for example, is the chalk hills of the Isle of Wight and south of England. But these are generally hills of an inferior height compared with our alpine schisti, and hardly deserve the term of mountain.

This material of our smooth green mountains may be termed an argillaceous schistus; it has generally calcareous veins, and is often fibrous in its structure resembling wood, instead of being slatey, which it is in general. There is however another species of schistus, forming also the same sort of mountain; it is the micaceous quartzy schistus of the north of Scotland. Now it must be evident that the character of those mountains arises from there being no part of those schisti that resists the influence of the atmosphere, in exfoliating and breaking into soil; and this soil is doubtless of different qualities, according to the nature of those schisti from which the soil is formed.

Such mountains are necessarily composed of rounded masses, and not formed of angular shapes. They are covered with soil, which is more or less either stoney or tender, sterile or fertile, according to the materials which produce that soil. The fertile mountains are green and covered with grass; the sterile mountains again are black, or covered with heath in our climates.

Thus we have a general character of smooth and rounded mountains; and also a distinction in that general character from the produce of the soil indicating the nature of the solid materials, as containing, either on the one hand calcareous and argillaceous substances, or, on the other, as only containing those that are micaceous and siliceous.

With regard again to the other species of mountain, which we have termed rocky, we must make a subdistinction of those which are regular, and those in which there is no regularity to be perceived. It must be plain that it is only of those which have regularity that we can form a theory. It is this, that the regularity in the shape of those mountains arises from the rock of the mountain being either on the one hand an uniform solid mass, or on the other hand a stratified mass, or one formed upon some regular principle distinguishable in the shape. In the first of these, we have a conical or pyramidal shape, arising from the gradual decay of the rock exposed to the destructive causes of the surface, as already explained in this chapter. In the second, again, we find the original structure of the mass influencing the present shape in conjunction with the destructive causes, by which a certain regularity may be observed. Now, this original shape is no other than that of beds or strata of solid resisting rock, which may be regularly disposed in a mountain, either horizontally, vertically, or in an inclined position; and those solid beds may then affect the shape of the mountain in some regular or distinguishable manner, besides the other parts of its shape which it acquires upon the principle of decay.

In distinguishing, at a distance, those regular causes in the form of mountains, we may not be able to tell, with certainty, what the substance is of which the mountain is composed; yet, with regard to the internal structure of that part of the earth, a person of knowledge and experience in the subject may form a judgment in which, for coming at truth, there is more than accident; there is even often more than probable conjecture. Thus, a horizontal bed of rock forms a table mountain, or such as M. Bouguer found in the valley of the Madelena. An inclined rock of this kind forms a mountain sloping on the one side, and having a precipice upon the upper part of the other side, with a slope of fallen earth at the bottom; such as the ridges observed by M. de Saussure from the top of the Cramont, having precipices upon one side, which also had a respect to certain central points, an observation which draws to more than the simple structure of the mountain. Were it vertical, again, it would form a rocky ridge extended in length, and having its sides equally sloped, so far as the other circumstances of the place would permit.

Therefore, whether we suppose the mountains formed of a rock in mass, or in that of regular beds, this must have an influence in the form of this decaying surface of the earth, and may be distinguished in the shape of mountains. It is but rarely that we find mountains formed altogether of rock, although we often find them of the other sort, where little or nothing of rock is to be seen. But often also we find the two cases variously compounded. This is the source of the difficulty which occurs in the reading of the external characters of mountains; and this is one of the causes of irregularity in the form of mountains, by which there is always some degree of uncertainty in our judgment from external appearances.

We may form another distinction with regard to the structure of mountains, a distinction which depends upon a particular cause, and which will afford an explanation of some other appearance in the surface of the earth.

Mountains in general may be considered as, being either on the one hand associated, or on the other insulated; and this forms a distinction which may be explained in the theory, and afford some ground for judging of the internal structure from the external appearance.

The associated mountains are formed by the wearing down of the most decayable, or softer places, by the collected waters of the surface; consequently there is a certain similarity, or analogy, of the mountains formed of the same materials, and thus associated. The highest of those mountains should be near the center of the mass; but, in extensive masses of this kind, there may also be more than one center. Nor are all the associated mountains to be of one kind, however, to a certain extent, similarity may be expected to prevail among them.

It must now be evident, that when we find mountains composed of very different materials, such as, e.g. of granite, and of lime-stone or marl, and when the shape of those mountains are similar, or formed upon the same principle, such as, e.g. the pyramidal mountains of the Alps, we are then to conclude, as has already been exemplified (chap. 9. page 306.) that those consolidated masses of this earth had been formed into the pyramidal mountains in the same manner. We have there also shown that this principle of formation is no other than the gradual decay of the solid mass by gravity and the atmospheric influences. Consequently, those pyramidal mountains, though composed of such different materials, may, at a certain distance, where smaller characteristic distinctions may not be perceivable, appear to be of the same kind; and this indeed they truly are, so far as having their general shape formed upon the same principle.

We come now to treat of insulated mountains. Here volcanos must be mentioned as a cause. By means of a volcano, a mountain may be raised in a plain, and a volcanic mountain might even rise out of the sea. The formation of this species of mountain requires not the wearing operations of the earth which we have been considering as the modifier of our alpine regions. This volcanic mountain has a conical shape, perhaps more from the manner of its formation which is accretion, than from the wasting of the surface of the earth. It is not, however, of this particular specie of mountain that I mean to treat, having had no opportunity of examining any of that species.

The genus of mountain which we are now considering, is that of the eruptive kind. But there is much of this eruptive matter in the bowels of the earth, which, so far as we know, never has produced a volcano. It is to this species of eruption that I am now to attribute the formation of many insulated mountains, which rise in what may be termed low countries, in opposition to the highlands or alpine situations. Such is Wrekin in Shropshire, which some people have supposed to have been a volcano. Such are the hundred little mountains in the lowlands of this country of Scotland, where those insulated hills are often called by the general term Law; as, for example, North Berwick Law.

When masses of fluid matter are erupted in the mineral regions among strata which are to form our land; and when those elevated strata are, in the course of time, wasted and washed away, the solid mass of those erupted substances, being more durable than the surrounding strata, stand up as eminences in our land. Now these often, almost always, form the small insulated mountains which are found so frequently breaking out in the lowlands of Scotland. They appear in various shapes as well as sizes; and they hold their particular form from the joint operation of two different causes; one is the extent and casual shape of the erupted mass; the other is the degradation of that mass, which is wasted by the influences of the atmosphere, though wasted slower than the strata with which it was involved.

When the formation of this erupted mass has been determined by the place in any regular form, which may be distinguished in the shape of a mountain, it gives a certain character which is often not difficult to read. Thus, our whin-stone, interjected in flat beds between the regular strata, often presents its edge upon, or near the summit of our insolated mountains and eminences. They are commonly in the form of inclined planes; and, to a person a little conversant in this subject, they are extremely distinguishable in the external form of the hill.

We have a good example of this in the little mountain of Arthur's Seat, by this town of Edinburgh. This is a peaked hill of an irregular erupted mass; but on the south and north sides of this central mass, the basaltic matters had been forced also in those inclined beds among the regular strata. On the north side we find remarkable masses of whin-stone in that regular form among the strata, and lying parallel with them. The most conspicuous of these basaltic beds forms the summit of the hill which is called Salisbury Craig. Here the bed of whin-stone, more than 60 or 80 feet thick, rises to the west at an angle of about 40 degrees; it forms the precipicious summit which looks to the west; and this is an appearance which is distinguishable upon a hundred other occasions in the hills and mountains of this country.

Rivers make sections of mountains through which they pass. Therefore, nothing is more interesting for bringing to our knowledge the former state of things upon the surface of this earth, than the examination of those valleys which the rivers have formed by wearing down the solid parts of alpine countries. We have already seen that the wide extensive valley of the Rh�ne, between Loiche and Kolebesche, as well as the whole extensive circus of the Rosa mountains, has on each side mountains of the same substances, the strata of which are horizontal; consequently, here the valley must have been hollowed out of the solid rock; for there is no natural operation by which those opposite mountains of horizontal strata could have been formed, except in the continuation of those beds. We are therefore to conclude, that the solid strata between those ridges of lofty mountains had been continuous.

The most perfect confirmation which this theory could receive, would be to find that those ridges of mountains, which the Rh�ne divides in issuing from the Alps into the plain, had been also united, in forming one continued mass of solid rocks. But the observations of M. de Saussure, who has most carefully examined this subject, will leave no room to doubt of that fact.

This view of the entry to the valley of the Rh�ne is too interesting not to give it here a place. It follows immediately after that which we have last transcribed.

�Ces montagnes que j'allai sonder au haut des prairies qui les s�parent de la grande route, sont compos�es d'un m�lange tr�s ressemblant au pr�c�dent, et ce sont-l�, les derniers rochers primitifs que l'on rencontre en sortant des Alpes par cette vall�e. Le village de Juviana, dont ils occupent les derri�res, est encore � une lieue de St Maurice.

�� 1062. A l'extr�mit� de ces rochers, on voit une grande ravine, ou plut�t une vall�e ouverte du nord au midi, dans laquelle coule le torrent de St. Barthelemi. Cette vall�e termine les montagnes primitives que je viens de d�crire: au-del� commencent les montagnes calcaires. Cependant le pied de la montagne primitive, coup� par le torrent, est demeur� engag� sous les premi�res couches de la montagne calcaire.

�Au travers de cette vall�e, on voit de hautes montagnes couverte de neige, situ�es derriere celles qui bordent notre route. La plus haute et la plus remarquable de ces montagnes se nomme la Dent ou l'Aiguille du Midi. De l'autre c�t� du Rh�ne, on voit une autre cime aussi tr�s-�lev�e, qui se nomme la Dent ou l'Aiguille de la Morele. Ces deux hautes cimes ont entr'elles une correspondance de hauteur, de forme, et m�me de mati�re tout-�-fait singuli�re. L'une et l'autre pr�sentent leurs escarpemens � la vall�e du Rh�ne. Leurs cimes cr�nel�es sont de la m�me couleur brune. Sous ces cimes brunes, on voit de part et d'autre une bande grise, qui paro�t horizontale, et au-dessous de cette bande grise, le rocher, dans l'une comme dans l'autre, reprend sa couleur jaun�tre. Ces montagnes sont s�rement secondaires, les bandes grises paroissent �tre de pierre � chaux, et les jaunes de schiste argilleux et de gr�s, � en juger du moins � cette distance, car je ne les ai point observ�es de plus pr�s. Elles paroissent aussi appartenir � des cha�nes secondaires qui passent derri�re les cha�nes primitives, que nous avons observ�es sur les bords du Rh�ne, et quoique les bandes jaunes et grises que l'on y observe, semblent horizontales, je ne doute point que les couches m�mes, dont ces bandes sont les sections, ne descendent en arriere avec assez de rapidit�; le escarpemens de ces montagnes en font une preuve �-peu-pr�s certaine.

�Ces hautes montagnes auroient-elles �t� anciennement li�es entr'elles par des interm�diaires de la m�me nature, que couvroient, et les primitives que nous avons observ�es, et toute cette vall�e dans laquelle coule aujourd'hui le Rh�ne? Je me garderois bien de l'affirmer, mais je ferois tent� de le croire.

�� 1063. Depuis la vall�e dont je viens de parler, et qui termine au couchant les montagnes primitives, celles qui suivent jusques � St. Maurice, sont de nature calcaire � couches �paisses et suivies. Ces couches s'�l�vent contre les primitives que nous avons c�toy�es; et celles qui en sont les plus voisines paroissent fort tourment�es; ici fl�chies, l� rompues. Apr�s une interruption, ces rochers sont suivis d'autres rochers, aussi calcaires, coup�s � pic du c�t� de la vall�e, et compos�s de grandes assises horizontales. Ces rochers forment une enceinte demi-circulaire, qui vient presque se joindre � ceux qui bordent la rive droite du Rh�ne, et former ainsi l'entr�e de cette vall�e, dont le fleuve ne sort que par une issue tr�s-�troite.

�La ville de St. Maurice est ainsi renferm�e par cette enceinte de rochers, dont les bancs �pais, bien suivis, s�par�s par des cordons de verdure, et couronn�s par des for�ts, avec un hermitage nich� entre ces bancs, pr�sente une aspect singulier et pittoresque.

�� 1064. Les rochers correspondans de l'autre c�t� du Rh�ne, ou sur la rive droite de ce fleuve sont aussi calcaires. La montagne qui domine cette rive, un peu au-dessus de St. Maurice, est compos�e de couches contourn�es, froiss�es et repli�es de la maniere la plus �trange. Ce qu'il y a encore de remarquable, c'est que ces couches ainsi repli�es en ont d'autres � c�t� d'elles qui sont planes, presque verticales, et d'autres sous elles, qui sont horizontales. Il faudroit avoir observ� de pr�s ce singulier rocher, et avoir d�termin� comment et jusqu'� quel point ces couches sont unies entr'elles pour former les conjectures sur leur origine. Car la vall�e est trop large pour que l'on puisse en juger avec pr�cision d'une rive � l'autre.

�On voit avec peine que cette large vall�e soit aussi peu cultiv�e; elle est presque partout couverte, ou de marais, ou de d�bris des montagnes voisines.

�� 1065. Avant de quitter cette vall�e, je jetterai un coup-d'oeil g�n�ral sur la singuli�re suite de rochers qui composent la cha�ne que nous venons d'observer.

�Les deux extr�mit�s sont calcaires, avec cette diff�rence, que celle qui est la plus pr�s de Martigny est m�l�e de mica, tandis que celle de St Maurice n'en contient point. Entre ces calcaires sont referm�es des rochers que l'on regarde comme primitives; et au milieu de ces roches on trouve des ardoises et des poudingues. On fait que ce dernier genre est ordinairement class� parmi les montagnes tertiaires, ou de la formation la plus r�cente. Mais ces poudingues-ci, qui ne contiennent aucun fragment de pierre calcaire, qui ne sont m�me point unis par un gluten calcaire, ne sont vraisemblablement pas post�rieures � la formation des montagnes calcaires, ou du moins ils ne doivent point �tre confondus avec ces gr�s et ces poudingues de formation nouvelle, qui entrent dans la composition des montagnes du troisi�me ordre.

�Quant aux ardoises que se trouvent interpos�es au milieu de ces gr�s et de ces poudingues, � 1054, elles sont de nature argilleuse, et dans l'ordre des pierres que l'on nomme secondaires.

�Ces ardoises, de m�me que toutes les pierres de ces montagnes, ont leurs couches dans une situation verticale: mais nous avons vu qu'il y a lieu de croire qu'elles ont �t� anciennement horizontales.�

It is singularly fortunate that such remarkable appearances, as are found in the rocks of this place, had called the attention of M. de Saussure to investigate a subject so interesting to the present theory; and it is upon this, as well as on many other occasions, that the value of those observations of natural history will appear. They are made by a person eminent for knowledge; and they are recorded with an accuracy and precision which leaves nothing more to be desired.

From Martigny to St. Maurice, about three leagues, there is a most interesting valley of the Rh�ne, through which this river makes its way from the Vallais, or great valley above, among those mountains which seem to have shut up the Vallais, and through which the river must pass in running to the lake. M. de Saussure found some singular masses, which attracted his attention, in examining the structure of the rocks on the left side of this little valley. Like a true philosopher, and accurate naturalist, he desired to compare what was to be observed in the other side of this valley of the Rh�ne, which he had found so singular and so interesting on that which he had examined. Accordingly, in Spring 1785, he made a journey for that purpose. In this survey he found the most perfect correspondence between the two sides of this valley, so far as rocks of the same individual species, and precisely in the same order, are found upon the one side and upon the other.

This author, after describing those particular appearances, sums up the evidence which arises from this comparison of the two sides of the valley; and he here gives an example of just reasoning, of accuracy, and impartiality, which, independent of the subject, cannot be read without pleasure and approbation. But when it is considered, that here is a matter of the highest importance to the present theory, or to any other system of geology, no less than a demonstration that the rocks, of which the mountains on both sides of the valley of the Rh�ne are formed, are the same, and must have been originally continued in one mass, the following observations of our author will be most acceptable to every person who inclines to read upon this subject.

�� 1079. On voit par cet expos�, que bien que la vall�e du Rlione ait dans ce trajet pr�s d'une lieue de largeur moyenne, les montagnes qui la bordent sont en general du m�me genre, et dans la m�me situation sur l'une et l'autre rive.

�Il y a cependant trois diff�rences que je dois exposer et appr�cier en peu de mots.

�La plus importante est dans ces couches de pierre calcaire, � 1073, que j'ai trouv�es sur la rive droite, et que je n'ai point vue sur la gauche. Mais il est possible qu'elles y soient, et qu'elles m'ayent �chapp�, masqu�es par des d�bris ou par d'autre causes accidentelles; cette supposition est d'autant plus possible, que l'�paisseur de ces couches n'est que de quelques pieds. D'ailleurs il arrive souvent, que des filons, tel que paro�t �tre celui dont je parle, ne s'�tendent pas � de grandes distances, quoique la nature de la montagne demeure la m�me. Enfin ce qui diminue l'importance de cette diff�rence, c'est que ces couches calcaires se trouvent dans le voisinage de l'ardoise qui passe, comme la pierre calcaire, pour une pierre de nature secondaire, et qui alterne tr�s-fr�quemment avec elle.

�Une autre difference que l'on aura pu remarquer, c'est que sur la rive droite, je n'ai point trouv� de petrosilex pur et en grandes masses, comme sur la rive gauche dans les environs de la cascade. Mais cette diff�rence ne me frappe pas non plus beaucoup; parce qu'au lieu de petrosilex, j'ai trouv� sur la rive droite des roches compos�es en tr�s-grande partie de feldspath. Or je regarde le p�trosilex et le feldspath comme des pierres de la m�me nature. Leur duret� est �-tr�s-peu-pr�s la m�me; leur densit� la m�me, leur fusibilit� la m�me; l'analyse chymique d�montre dans l'un et dans l'autre les m�mes principes, la terre siliceuse, la terre argilleuse et le fer; et de plus ces ingr�diens s'y trouvent � tr�s-peu-pr�s dans les m�mes proportions. Il ne reste donc de diff�rence que dans la couleur et dans l'agr�gation des �l�mens. Or on fait que ces qualit�s accidentelles tiennent souvent � des causes qui peuvent �tre purement locales.

�La troisi�me diff�rence, celle qui se trouve dans la direction de quelques-unes des couches, je l'ai d�j� indiqu�e, � 1075. et il semble inutile de r�p�ter, que quand des couches form�es originairement dans une situation horizontale, ont �t� redress�es par des op�rations violentes de la nature, il n'y a pas lieu de s'�tonner qu'elles n'aient pas exactement la m�me position dans tout l'espace qu'elles occupent.

�Les diff�rences ne sont donc pas tr�s-significantes, et les ressemblances sont au contraire du plus grand poids. Ce qui leur donne � mon gr� la plus grande force, c'est la raret� des pierres dont ces montagnes sont compos�es, ces esp�ces de porphyres � base de p�trosilex, ces rochers feuillet�es m�lang�es de feldspath et de mica; c'est encore la correspondance de l'ordre dans lequel elles se suivent; ces bancs de poudingues s�par�s par des ardoises sur une rive comme sur l'autre; leur situation �galement ou �-peu-pr�s telle. Viola de grandes et fortes analogies et qui ne permettent pas de douter que ces montagnes, produites dans le m�me temps et par les m�mes causes, n'aient �t� anciennement unies.�

Having thus shown, that the Rh�ne had in the course of time hollowed out its way from the central mountain of the St. Gothard through the extensive valley of the Vallais we may still further trace the marks of its operation in the more open country towards the lake. It is an observation which M. de Saussure made in his way from the valley of the Rh�ne to Geneva.

�� 1090. La grande route de Bex � Villeneuve suit toujours le fond de la vall�e du Rh�ne, en c�toyant les montagnes qui bordent la droite ou le cot� oriental de cette vall�e. Ces montagnes sont en g�n�ral de nature calcaire, mais on voit � leur pied, jusques aupr�s de la ville d'Aigle, situ�e � une lieue et demi de Bex, la continuation des collines de gypse qui renferment les sources sal�es.

�� 1091. A l'opposite de ces collines, au couchant de la grande route, on voit sortir du fond plat de la vall�e deux collines allong�es dans le sens de cette m�me vall�e. Ces collines sont l'une et l'autre d'une pierre calcaire dure et escarp�es presque de tous les c�tes. L'une la plus voisine de Bex, ou la plus m�ridionale, se nomme Charpigny, l'autre Saint Tryphon.

�Il paro�t �vident que ces rochers isol�s au milieu de cette large vall�e sont de noyaux plus dures et plus solides qui ont r�sist� aux causes destructrices par lesquelles cette vall�e � �t� creus�. Ils ne sont cependant pas exactement de la m�me nature, et surtout pas de la m�me structure; car celui de Saint Tryphon est compos� de couches r�guli�res, horizontales ou �-peu-pr�s telles, tandis que celui de Charpigny a les siennes tr�s-inclin�es et souvent dans un grand d�sordre.�

In M. de Saussure's Journey to the Alps, we have now seen a description of the shape that had been given to things, by those operations in which strata had been consolidated and elevated above the sea; nothing but disorder and confusion seems to have presided in those causes, by which this mass of continent had been exposed to the sight of men; and nature, it would appear, had nothing in view besides the induration, the consolidation, and the elevation of that mass into the snowy regions of the atmosphere. From the descriptions now given, we see the operation of the waters upon the surface of the earth; we perceive a regular system of mountains and valleys, of rivulets and rivers, of fertile hills and plains, of all that is valuable to the life of man, and that which is still more valuable to man than life, viz. the knowledge of order in the works of nature, and the perception of beauty in the objects that surround him.

Let us now turn our view to distant regions, and see the effect of causes which, being general, must be every where perceived.

The Theory illustrated, by adducing examples from the different Quarters of the Globe

The system which we investigate is universal on this earth; it hangs upon, the growth of plants, and life of animals; it cannot have one rule in Europe, and another in India, although there may be animals and plants, the constitutions of which are properly adapted to certain climates, and not to others. The operation of a central fire, in making solid land on which the breathing animals are placed, and the influences of the atmosphere, in making of that solid land loose soil for the service of the vegetable system, are parts in the economy of this world which must be every where distinguishable. But this the reader is not to take upon my bare assertion; and I would wish to carry him, by the observations of other-men, to all the quarters of the globe.

Mr Marsden, without pretending to be a natural historian, gives us a very good picture of the water-worn surface of Sumatra. History of Sumatra, page 20.

"Along the western coast of the island, the low country, or space of land which extends from the sea shore to the foot of the mountains, is intersected and rendered uneven to a surprising degree, by swamps, whose irregular and winding course may in some places be traced in a continual chain for many miles till they discharge themselves either into the sea, or some neighbouring lake, or the fens that are so commonly found near the banks of the larger rivers, and receive their over flowings in the rainy monsoons. The spots of land, which these swamps incompass, become so many islands and peninsulas, sometimes flat at the top, and often mere ridges; having in some places, a gentle declivity, and in others descending almost perpendicularly to the depth of an hundred feet. In few parts of the country of Bencoolen or of the northern districts adjacent to it, could a tolerable level space of four hundred yards be marked out: about Soogey-lamo in particular, there is not a plain to be met with of the fourth part of that extent. I have often from an elevated situation, where a wider range was subjected to the eye, surveyed with admiration the uncommon face which nature assumes, and made enquiries and attended to conjectures on the causes of those inequalities. Some chose to attribute them to the successive concussions of earthquakes, through a course of centuries. But they do not seem to be the effect of such a cause. There are no abrupt fissures; the hollows and swellings are for the most part smooth and regularly sloping, so as to exhibit not unfrequently, the appearance of an amphitheatre, and they are clothed with verdure from the summit to the edge of the swamp. From this latter circumstance, it is also evident that they are not, as others suppose, occasioned by the falls of heavy rains that deluge the country for one half of the year. The most summary way for accounting for this extraordinary unevenness of the surface were to conclude, that in the original construction of our globe, Sumatra was thus formed by the same hand which spread out the sandy plains of Arabia, and raised up the Alps and Andes beyond the regions of the clouds." Our author then, after reprobating this idea, endeavours to explain the appearance here examined by the constant though imperceptible operation of springs. The present purpose is not so much concerning the explanation of those appearances, as to inquire if these be the general appearances of things over all the surface of the earth.

The general appearance here is that of land washed away upon the surface by water, which has every where left the marks of its operation in the shape of the ground. As for any particulars in the shape of this water-worn surface, this can only be explained in knowing the nature of the soil and solid parts, and the circumstances of the operation in which they have been wasted.

If the shape of the land here described by Mr Marsden has been produced by means of water, it must be by water moving from a higher to a lower place; and, in that respect, it is the same operation which every where prevails, in producing similar effects, although it is not every where that this effect comes to be the object of our notice. It is therefore so necessary to illustrate, in giving a diversity of cases. But it is not every case that can be understood as belonging to this rule; for, though the shape of every part has been modified by the operation of this cause, it is not every where that this relation of cause and effect is immediately perceived. There must be a certain regularity in the parts to be described, and a certain conformity wish those in which we have no doubt, or in which we certainly acknowledge the efficacy of the cause.

In America, this system of swamps and savannas are to be found upon a large scale; but for this very reason, they are not so remarkable to men. Man only sees a system of things, so far as that system is more immediately within the reach of his perception; for, without having prepared media, by which he may compare things that are distant either in their nature or their place, How could he judge those things to be connected in a system? It is in this manner that, seeing only the small part of an extended system of things, he sees no system in it, and, consequently he cannot give any scientifical description of the subject.

There is another case in which men of science, or systematising men, are apt to fall into delusion: it is not from any deficiency of seeing effects, and knowing general causes; it is from the misapplication of known causes to effects which are perceived. We have a remarkable example of this in the view which M. de Bouguer has taken of a singular appearance which he met with, perhaps more interesting to the present Theory than almost any other of which we know. (Voyage au P�rou, page 89.)

�Une particularit� qui a attir� souvent mon attention dans toutes ces contr�es, c'est que toutes les montagnes aupres desquelles je passois, et qui sont au pied et au dehors de la grande Cordeli�re, me paroissoient avoir eu une origine toute diff�rente de celles que j'avois vues auparavant. Les lits de diff�rentes terres et le plus souvent de rochers dont elles �toient form�es, n'�toient pas inclin�s de divers c�t�s, comme dans les autres: ils �toient parfaitement horizontaux, et je les voyois quelquefois se r�pandre fort loin dans les diff�rentes montagnes. La plupart de celle-ci ont deux ou trois cent toises de hauteur, et elles sont presque toutes inaccessibles; elles sont souvent escarp�es comme des murailles: c'est ce qui permet de mieux voir leurs lits horizontaux dont elles pr�sentent l'extr�mit�. Le spectacle qu'elles fournissent n'est pas riant, mais il est rare et singulier. Lorsque le hazard a voulu que quelqu'une f�t ronde, et qu'elle se trouv�t absolument d�tach�e des autres; chacun de ses lits est devenu comme un cylindre tr�s-plat, ou comme un c�ne tronqu� qui n'a que tr�s-peu de hauteur; et ces diff�rens lits plac�s les uns au-dessus des autres, et distingu�s par leurs couleurs et par les divers talus de leur contour, ont souvent donn� au tout la forme d'ouvrage artificiel et fait avec la plus grande r�gularit�. Il est une de ces montagnes � environ une lieue de Honda sur le bord du Guali et sur le chemin de Mariquita, qui est expos�e � la vue de tous les voyageurs; mais je sens que si j'en donnois ici une repr�sentation, il faudroit que je comptasse sur le credit que doit naturellement avoir le rapport de quelqu'un qui n'a aucun int�r�t d'alt�rer la v�rit�, et qui a en toute sa vie le plus grand �loignement pour le mensonge. On voit dans ces pays l� les montagnes y prendre continuellement l'aspect d'anciens et somptueux �difices, de chapelles, de d�mes, de ch�teaux; quelquefois ce sont des fortifications form�es de longues courtines munies de boulevarts. Il est difficile lorsqu'on observe tous ces objets et la mani�re dont leurs couches se r�pondent, de douter que le terrain ne se soit abaiss� tout autour. Il paro�t que ces montagnes dont la base �toit plus solidement appuy�e, sont rest�es comme des esp�ces de t�moins ou de monumens qui indiquent la hauteur qu'avoit anciennement le sol.�

There are but two ways in which those appearances may be explained; one of these is that which M. Bouguer has adopted; the other, again, belongs to the present Theory, which represents the action of running water upon the surface of the earth as instrumental in producing its particular forms, and thus forming many natural appearances upon the surface of the earth. The first of these, viz. that a mass of solid land, in such a shape as that here described, should remain while all around it sinks, is an opinion which, however possible it may be, is not supported, I believe, by any example in nature; the last again, viz. that the parts around those insulated masses, and those that had intervened between the corresponding mountains, have been carried away by the natural operation of the rivers, is not only the most easy to conceive, but is also, so far as those operations are concerned, conform to every appearance upon the surface of the globe. It is not necessary to go to South America, and the rivers of the Cordeliers, for examples to illustrate that which every one may see performed almost at his own door; but it is there that an example has occurred, which, though it has imposed upon an eminent philosopher, cannot properly be employed in support of any other theory but the present. Our author proceeds:

�Je ne connois les environs de l'Or�noque que par relation, mais je s�ais qu'en plusieurs endroits les montagnes y sont �galement form�es de couches horizontales, et qu'elles ont souvent en haut des plateformes qui sont exactement de niveau. On ne trouve � ce que je crois rien de semblable au P�rou malgr� la vari�t� presque infinie qui y est r�pandue. Toutes les couches y vont en s'inclinant autour de chaque sommet, en se conformant � la pente des collines.�

It would appear that it is a rare thing to find a great extent of indurated strata in a horizontal position. Now, this circumstance is necessary in affording the appearances here considered; those particular appearances, therefore, are only to be found more partially in other places, where the strata are inclined. If here, therefore, where the strata are horizontal, and where the spaces between the summits of those mountains had evidently been as solid as the masses which remain, we find mountains formed by the waste of land, and a system of rivers forming valleys amidst these mountains, Have we not reason to conclude, that in other mountainous regions, where the regular position of the strata has been broken and confounded, and where the same system of river and valley universally is found, the form of the surface has been produced upon no other principle than that of the natural waste of the solid mass, and the washing down of the heights for the formation of the fertile plains?

Nothing can tend more to illustrate the Theory than a proper comparison of the Old World with that which is called the New. It is not that we are to expect to see the operation of a longer time, upon the one of those continents, compared with the other; we equally lose all measure of time, in tracing the operations of nature on either continent. But in those operations there is rule to be observed; and the question is, If the same order of things may be perceived in all the quarters of the globe?

This is a question which the learned, even, in their closet, may be able to decide. They have but to look at the maps to be convinced that every where the process of nature, in forming habitable countries, is uniform; and that the system of what is called the watering those countries with rivers, is universally the same; a system which is now considered as giving us a view of the operations of water wearing down the land which it has fertilized, and shaping the surface of the earth so as to make it on the whole most useful.

There cannot be a doubt of the effects of those natural operations which belong to the surface of the earth, and which affect more powerfully the surfaces of the mountains; the only question is with regard to the general amount of those operations, and to the particular occasions which may have concurred in producing those effects. These questions can only be resolved in making particular observations. A general theory may thus be formed, of those operations by which the surface of the earth above the level of the sea has been changed, and will continue to be so as long as it remains a surface exposed to the influence of those agents which must be acknowledged in this place.

Naturalists, who have examined the various parts of the earth, almost all agree in this, that great effects have been produced by water moving upon the surface of the earth; but they often differ with respect to the cause of that motion, and also as to the time or manner in which the effect is brought about. Some suppose great catastrophes to have occasioned sudden changes upon the surface, in having removed immense quantities of the solid body, and in having deposited parts of the removed mass at great distances from their original beds. Others again, in acknowledging the natural operations which we see upon the surface of the earth, have only supposed certain occasions in which the consequence of those natural operations have been extremely violent, in order to explain to themselves appearances which they know not how to reconcile with the ordinary effects of those destructive causes.

The theory of the earth which I would here illustrate is founded upon the greatest catastrophes which can happen to the earth, that is, in being raised from the bottom of the sea, and elevated to the summits of a continent, and in being again sunk from its elevated station to be buried under that mass of water from whence it had originally come. But the changes which we are now investigating have no farther relation to those great catastrophes, except in so far as these great operations of the globe have put the solid land in such a situation as to be affected by the atmospheric influences and operations of the surface.

The water from the atmosphere, collected upon the surface of the earth, forms channels to itself in running towards the sea or lower ground; and it is these channels, increasing in their size as they are diminished in number by the uniting of their waters, that give so clear a prospect of the operations of time past, and prove the theory of the land being in a continual state of decay, and necessarily wasted for the purpose of this world. Every description, therefore, of a river and its valleys, from its sources in the mountains to its mouth where it delivers those waters to the sea, is interesting to the present theory, which is the generalization of those facts by which the end or intention of nature is to be observed. M. Reboul, in a Memoir read to the Academy of Sciences at Paris in 1788, has given a very distinct view of the Vall�e du Gave B�arnois dans les Pyr�n�es; there are many things interesting in this memoir; and I shall now endeavour to avail myself of it.

�Le torrent qui porte le nom de Gave de Pau parcourt depuis sa source pr�s des limites de l'Espagne, jusqu'� la petite ville de Lourde, une vall�e qui se dirige du sud au nord sur une longueur d'environ dix lieues. Cet espace, qui forme son lit dans l'int�rieur des Pyr�n�es, ressemble moins � une vall�e dans la majeure partie de son �tendue, qu'� une entaille �troite et profonde, dont les flancs sont souvent coup�s � pic d'une hauteur effrayante, et dont le fond est toujours couvert d'une eau �cumeuse. Cette long coupure se termine, ainsi que plusieurs de ses branches, aux sommets les plus �lev�s des Pyr�n�es, et elle re�oit les eaux qui distillent sans cesse de leur neiges durcies. Sa division g�ographique est en deux vall�es, dont l'une plus voisine de la plain est appel�e Lavedan, et dont l'autre ne fait que partie de la contr�e qui porte le nom de Bar�ges.�

From the summit of that ridge of mountains which run from the Atlantic to the Mediterranean, the vallies of the principal rivers run from the south northward towards the plain of France; from this again they turn westward in order to find their way to the sea. The mountains, which then separate these rivers from the plain, are composed of schistus and great collections of water-worn gravel which had come from the mountains of the Pyr�n�es.

Upon this occasion Mr Reboul observes: �Les ruines amoncel�es et la grand quantit� de cailloux roul�s qui forment ces digues naturelles, invitent sans doute � penser que ce sont les torrens eux-m�mes qui ont combl� leur lit et obstru� leur passage, mais on ne peut concevoir que cet effet ait pu avoir lieu que dans des tems tr�s-recul�s, et avant l'enti�re excavation des vall�es. Peut-�tre paro�tra-t-il naturel d'imaginer que les masses out �t� produites par le conflit des eaux qui se pr�cipitoient des montagnes et des flots de la mer, lorsqu'elle recouvroit encore les plaines, etc.

�Je ne fatiguerai point le lecteur du d�nombrement inutile de tous les bancs pierreux de ces substances qui se succ�dent le long de la vall�e, et prenant seulement le r�sultat de mes observations, je me bornerai � dire que depuis Lourde jusqu'� Luz, les parois de la gorge sont alternativement compos�es de mati�res argilleuses et calcaires, quelquefois sous la forme de couches diversement inclin�es, mais plus souvent fissiles, montrant de feuillets de diff�rentes grandeurs et d'un tissu plus ou moins compacte. Ces schistes h�t�rog�nes sont presque toujours entass�s et superpos�s dans la m�me montagne, mais en plusieurs endroits un seul genre pr�domine, etc. L'esp�ce d'uniformit� qui semble exister dans la composition de ces masses, ne se trouve nullement dans leurs disposition; on chercheroit en vain dans leurs couches une direction et une inclinaison g�n�rale et constante, on pourroit tout au plus hazarder � ce sujet de l�g�res conjectures; mais si l'ordre primitif de ces montagnes est d�rob� � l'oeil de l'observateur, on trouve � chaque pas des indices certains, des marques �videntes de la mani�re dont il a �t� alt�r� ou d�truit.

�Je reconnus d'abord que les m�mes cailloux, les m�mes d�bris de marbre et d'ardoise qui couvraient le fond de la vall�e, et que le Gave entra�ne et remplace sans cesse, se trouvent aussi � plusieurs toises au-dessus de son niveau. Je voyois quelquefois les s�dimens fluviatiles recouverts et ensevelis sous des grandes masses de pierre feuillet�e adh�rente � la montagne; levant ensuite les yeux, j'observai que de l'un ou de l'autre c�t� du torrent, les flancs des montagnes �toient souvent couverts et comme plaqu�s de semblables masses de schiste, dont les couches et les feuillets offroient toujours des directions contraires � celles des schistes de m�me nature, auxquels ils �toient adoss�s. Les eaux du torrent, qui ont sans doute renvers� ces couches sur elles-m�mes, y ont d�pos� des marques de leur passage; elles ont abandonn�, engag� sous ces d�bris m�mes, � des grandes hauteurs, des blocs �normes de granit que le voyageur surpris voit pendre sur sa t�te; de pareils blocs arrondis et us�s couvrent le fond de la vall�e, et opposent quelquefois au torrent une digue qui le fait jaillir et retomber en �cume; enfin j'ai suivi les traces de ce courant aux diff�rentes hauteurs des parois du canal o� il coule aujourd'hui � plusieurs centaines de toises de profondeur. Il a d� les parcourir toutes successivement en creusant et r�tr�cissant sont lit et augmentant sa vitesse.

�Les cr�tes des sommit�s qui forment les bords les plus �lev�s de la gorge, sont escarp�es dans la direction du courant. J'ai aper�u quelquefois des portions de montagnes s�par�es de la cr�te, ou du sommet principal, et dont les eaux semblent en avoir fait des esp�ces d'�les, en creusant autour d'elles un foss� profond, o� l'on voit fort bien les angles saillans de l'�le correspondre aux angles rentrans de la montagne, etc.

�Dans la partie de la vall�e o� s'observent ces ph�nom�nes, on marche toujours entre deux montagnes resserr�es, dont les nuage d�robent souvent les cimes, mais par-tout o� les eaux de quelque torrent consid�rable viennent se r�unir � celles du Gave, il s'est form� un bassin d'une �tendue moyenne, qui ne fut d'abord vraisemblablement qu'une grande mare d'eau semblable � ces lacs qui existent encore dans le sein des Pyr�n�es et des Alpes. Ainsi on voit, � une lieu avant Argel�s, les montagnes s'�carter, se replier en un vaste circuit, et entourer, comme d'une muraille st�rile et ruineuse, des prairies arros�es par mille canaux et par le brouillard des cascades; des coteaux, o� l'on voit s'�lever, parmi les vergers et les bois, des villages orn�s de marbre, des ch�teaux majestueux et les d�licieuses habitations de quelques moines fortun�s.

�Le penchant qui borde ce vallon du c�t� de l'est n'est creus� que par quelques ravins tr�s-inclin�s, dont les eaux se pr�cipitent en �cume et disparoissent, avant d'arriver au bas de la montagne, sous l'ombre des bois et d'une foule d'habitations rustiques: mais le penchant de l'ouest, plus profond�ment excav� par les torrens, pr�sentent les issues de trois autres vall�es, dont les deux principales vont prendre leurs origine aux limites de l'Espagne; l'autre, plus voisine de la plaine, est �-peu-pr�s dirig�e de l'est � l'ouest. Elles s'appelle Estrem de Sales, et joint ses eaux � celles du Gave un peu au-dela de l'extr�mit� int�rieure de ce grand bassin qu'elle a concouru � former. C'est au centre du bassin, aupr�s du village d'Argel�s, que le Gave d'Azun arrive avec fracas, et c'est � son extr�mit� sup�rieure que le Gave de Cautr�s s'y pr�cipite en sortant d'une gorge dont l'aspect frappe d'�tonnement et d'horreur. Le cours de ces deux Gaves est aupr�s de leur embouchure oblique � celui du Gave principal; mais ils se replient ensuite vers le centre de la cha�ne et deviennent presque parall�les. Aupr�s de Luz se d�couvre un autre bassin o� se joignent les eaux du Gave � celles du torrent de la Lise, qui n'a creus� qu'un ravin, et � celles du Bastan qui descend d'un vallon tr�s-�vas� dans la direction de l'est � l'ouest, o� se trouvent les eaux min�rales de Bar�ges. Ce nouveau bassin n'offre que le spectacles d'une vaste prairie bord�e de montagnes prodigieuses. Je n'entreprendrai point de rien ajouter ici touchant ces diverses branches de la vall�e du Gave B�arnois; chacune d'elles exigeroit une description d�taill�, soit � cause de son �tendue, soit � cause de la vari�t� de ses ph�nom�nes.

�De Luz � Gavarnie le Gave se trouve de nouveau resserr� dans une gorge �troite o� les montagnes paroissent encore s'�lever et les ab�mes s'enfoncer; ses eaux ne coulent plus qu'en cascades bruyantes, et quelquefois le voyageur, qui les voit �cumer sous ses pieds du haut du sentier trac� sur la montagne, entend � peine un murmure lointain. On y remarque de nouveau les ph�nom�nes, d�crit ci-devant, des pierres feuillet�es renvers�es de leur premi�re direction, des bancs entiers courb�s et bris�s dans leur ch�te, des d�bris granitiques arrondis par les eaux, d�pos�s � de tr�s-grandes hauteurs dans le fond des ravins o� le courant n'existe plus, etc.

�A G�dre le Gave re�oit les eaux de H�as, lieu devenu c�l�bre et enrichi par la d�votion Espagnole. A peine a-t-on pass� le torrent, que le granit commence � paro�tre. Le Gave roule ses eaux sur cette base qu'il entame difficilement: aussi son lit est-il plus large et la gorge moins profonde: le granit se montre enterr� sous de grandes montagnes calcaires. Du c�t� de l'ouest il est presque toujours recouvert de ces masses qu'on distingue de loin � leur teinte grise et blanch�tre m�l�e de sillons d'un rouge peu fonc�. A l'est les montagnes calcaires laissent le granit � d�couvert, et lui demeurent comme adoss�es. Celles qui leur succ�dent offrent des marques, effrayantes de d�cr�pitude; leurs cr�tes sont d�mantel�es, et leurs flancs sont l�sard�s et h�riss�s de rochers suspendus. Le fond de la vall�e semble enseveli sous les d�bris de cette montagne � demi �croul�es. On trouve, parmi les ruines, des blocs de plusieurs milliers de pieds cubes. Le Gave les couvre quelquefois de ses eaux, se pr�cipite dans les intervalles qu'ils laissent entr'eux, et rena�t comme sous une vo�te affaiss�e. Plusieurs de ces lambeaux affectent sur leurs plans la forme de parall�logrammes et de rectangles; mais ceux que l'on voit encore attach�s au corps de la montagne, sont pour la plupart pyramidaux, et sa cr�te est form�e d'une suite de ces pyramides granitiques. Toutefois on ne peut pas se refuser � voir que le granit est ici dispos� en couches tr�s-distinctes qui paroissent surmont�es dans quelques points des sommit�s, de bancs calcaire. La direction de ces couches granitiques n'est pas constante dans toute la masse; elles semblent s'incliner vers le sud-ouest du c�t� de Gavernie, et vers le nord-est du c�t� de G�dre. Quoique leurs substance soit m�l�es de plusieurs roches h�t�rog�nes, elle est g�n�ralement compos�es de quartz, de feld-spath, et de mica; mais ces deux substances y sont dans un �tat frappant de d�composition, et semblent quelquefois r�duites en chaux de fer.

�Au-del� de leurs d�bris, dont l'amas est d�sign� par le montagnards sous le nom de Peyrade et sous celui de Catios par les gens du monde, le granit est de nouveau surmont� de substances calcaires. Il sort de base aux pics coniques de Caumelie et de Pimen�. Cette base forme elle-m�me une vaste montagne qu'on appelle Allans; ses roches, d'un granit ferrugineux et sombre, sont entour�es d'une couronne blanch�tre et calcaire, o� v�g�tent quelque sapins �pars: Gavarnie est � ses pieds.

�C'est � une l�g�re distance de ce village, que se termine la vall�e du Gave B�arnois, ou plut�t qu'elle prend naissance avec le torrent qui l'a form�e. On apper�oit de loin les vastes sommets et les champs �lev�s de neige et de glace d'o� ses eaux se pr�cipitent; on reconno�t ensuite qu'ils ne forment qu'une montagne ou plut�t une masse �norme par sa hauteur et son volume, compos�e d'une m�me mati�re, et qui, plac�e sur une base vers laquelle on n'a cess� de monter pendant l'espace de dix lieues, s'�l�ve tout-�-coup de sept � huit cens toises, et domine au loin toutes les montagnes qui l'entourent. Les diff�rens sommets dont elle est couronn�e se pr�sentent sous mille formes bizarres; ce sont des pyramides irr�guli�res et de vastes cylindres, ou de c�nes tronqu�s pr�s de leur base, qui ressemblent assez � des tours �cras�es. Les cr�tes, qui sont form�es du prolongement de ces sommit�s, sont autant de murailles inaccessibles bord�es d'un long tas de ruines ou d'un large foss� de neige glac�e, et quelquefois interrompues par de br�ches profondes. On ne peut apercevoir tous ces objets du fond de la vall�e, et il faut s'�lever sur quelque hauteur voisine, telle que le sommet de Bergons, ou celui de Pimen�, pour embrasser toutes les parties de ce vaste tableau. En remontant vers les sources du Gave, qui en occupe le centre, on p�n�tre par un coupure peu profonde dans une prairie de forme ovale assez r�guli�re bord�e � l'est et � l'ouest par des hauteurs plant�es de sapins et de h�tres, et au sud par un amas de rochers �croul�s, et par les sommets que je viens de d�crire. Le Gave y serpente sur un lit de sable et de cailloux, et re�oit les eaux qui descendent, en �cumant, des hauteurs voisines; il se fraie un chemin vers cette prairie parmi les d�bris entass�es qui la bornent au sud, et qui la s�parent d'une autre bassin non moins vaste, o� le torrent commence son cours, et o� la montagne s'�l�ve tout autour en un rempart inaccessible.

�On peut prendre une id�e l�g�re et imparfaite de cette majestueuse enceint, en se la figurant comme un amphith��tre moins remarquable par la vaste �tendue de son ar�ne que par la hauteur prodigieuse de ses murs qui, par-tout bord�s de parties saillantes, d'�chancrures profondes, et h�riss�s de rochers dont la ruine est prochaine, se sont enti�rement �croul�s du c�t� du nord; elle-est couronn�e vers le sud par deux sommets cylindriques recouverts d'une cro�te �paisse de neige durcie, et que leur forme a fait nommer tour de marbre. Au-dessous se succ�dent, en forme de gradins, de vastes platte bandes d'une neige qui ne disparo�t jamais, et qui ne cesse point de se fondre insensiblement. Les eaux produites par cette stillation continuelle se divisent en sept ou huit petits torrens qui naissant sous ces lits de glace, et roulent sur le penchant rapide de la montagne ou jaillissent en cascades, quand elle se trouve coup�e a pic. L'un de ces torrens venant du c�t� de l'est et dont le volume surpasse celui de tous les autres ensemble, se pr�cipite du haut d'un rocher qui s'avance en saillie, et tombe avec un bruit horrible � plus de 1200 pieds de profondeur. Ses eaux, divis�es dans les airs et r�duites comme en poussiere, forment autour de la cascade un brouillard suspendu qui d�robe aux yeux du spectateur tout son volume et la vitesse de sa chute. L'ar�ne ou se r�unissent toutes ces eaux et o� commence le Gave, est de forme irr�guli�re; sa surface in�gale offre tant�t de grands plateaux de neige, des blocs de rochers �croul�s et d'autre d�bris att�nu� et r�duits � l'�tat terreux o� v�g�tent de belles plantes que le soleil �claire � peine. Le Gave, en tombant sur les amas de neige, y a creus� un gouffre au fond duquel le soleil avant son d�clin peint le cercle color� de l'iris. Les eaux disparoissent sous la neige et renaissent ensuite comme sous un pont �troit ou sou la vo�te d'un aqueduc; elles serpentent, se replient � travers les ruines amoncel�es, et surmontent les obstacles qui s'opposent � leur sortie.

�Si l'aspect magnifique et la beaut� sauvage de cette enceinte sont difficiles � repr�senter, sa structure n'en est pas moins facile � saisir; et dans ce lieu, qui semble fait pour le tourment du peintre de la nature, elle se d�couvre sans peine au yeux de l'observateur et de l'historien. La grande enceinte de la cascade de Gavarnie, dit M. d'Arcet, fut un lac autrefois: l'aspect des lieux fait na�tre naturellement cette id�e. Dans la suite les rochers qui la fermoient sur le devant, s'�tant d�truits, les eaux se sont �coul�es et perdues.

�On ne peut se refuser � croire avec M. d'Arcet, que l'enceinte des cascades de marbre n'ait �t� autrefois un lac. Le nombre et l'�tendue de ces amas d'eau diminuent tous les jours dans les Pyr�n�es comme dans tout pays de montagnes; les eaux qui viennent s'y rendre en exhaussent le fond par les cailloux et les d�bris terreux qu'elles y entra�nent, et celles qui s'�coulent en abaissent le niveau, en creusant insensiblement le canal par lequel elles sortent. Ainsi la marche lente et progressive de la nature sans l'interm�de des accidens et de r�volutions, suffit pour combler ces vastes creuse o� les eaux se sont amass�es, ou pour ouvrir des issues qui ne leur permettent plus d'y s�journer. Le nombre de ces lacs abandonn�s et perdus n'est gu�re au-dessous de celui de lacs encore existans. Les naturels du pays ont appris eux-m�mes � distinguer ces monumens naturel; ils ont saisi leur structure semblable � celle d'un vaisseau �vas� et coup� dans ses parois d'une ou de plusieurs entailles profondes, et les ont tous d�sign�s par le mot oule, qui d�rive du mot Latin olla, et signifie chez eux marmite; comparaison aussi juste que peu noble et bien digne de ces observateurs froids, mais exacts, �galement d�pourvue de pr�vention et d'enthousiasme. Ces oules se trouvent souvent plac�es aux extr�mit� sup�rieurs des vall�es, � l'origine des torrens qui les remplissoient autrefois. En effect, ceux-ci naissent commun�ment sous quelque vaste amas de neige, ou s'�coulent d'un r�servoir qui rassemble les eaux des hauteurs voisines. Le nombre de ces lacs augmente � mesure qu'on s'�l�ve, et c'est une observation g�n�rale, que ceux des vall�es sont pour la plupart combl�s ou perdus, et que ceux des montagnes, surtout de celle de granit, sont presque tous conserv�s. J'ai dit pr�c�demment, d'apr�s l'observation de M. d'Arcet, que l'enceinte des cascades pr�sentoit la forme d'un r�servoir entr'ouvert et �puis�, et qu'elle �toit pr�c�d�e d'un autre bassin dont l'aspect est moins sauvage et la forme plus r�guli�re. Tout porte � penser que celui-ci a �t� aussi long-tems rempli d'eau, ou plut�t il r�sulte d'un examen d�taill� de ces lieux, que le deux bassins ne faisoient autrefois qu'un seul et immense r�servoir, o� les eaux �toient retenues � deux ou trois cens toises d'�l�vation au-dessus du sol o� elles coulent aujourd'hui. Les rochers qui s�parent le premier bassin de l'enceinte des cascades, ne sont, comme je l'ai d�j� remarqu�, qu'un vaste amas de d�bris; mais ces d�bris ne ressemblent point � ceux d'une muraille renvers�e sur elle-m�me, ou d'une digue rompue par l'effort des eaux. Il est au contraire ais� de se convaincre qu'ils ont �t� d�tach�s de cette partie de la montagne qui bord l'enceinte du c�t� de l'est, et sur laquelle sont les sommets les plus �lev�s de toute cette masse. On voit encore sur ses flancs d�chir�s pendre d'�normes quartiers de roche pr�ts � s'�crouler. Ceux qui sont d�j� tomb�s ont demeur� entass�s les uns sur les autres. L'amas qu'ils ont form� est adoss� � la montagne dont ils faisoient jadis partie, et s'incline jusqu'aux parois oppos�e de l'enceinte. Le torrent qui la traverse se trouve ainsi rejet� du c�t� de l'ouest, et le lit qu'il a creus� suit les contours de cet amas de d�bris. Un tems a donc exist� auquel les deux enceintes dont j'ai parl�, �tant remplies d'eau, ne formoient qu'un seul lac vaste et profond; et peut-�tre la m�me r�volution qui les a s�par�es a-t-elle chang� tout-�-fait leur forme et caus� l'enti�re dispersion de leurs eaux; car si l'on consid�re que l'enceinte du bassin de la prairie est enti�rement d�truite du c�t� du nord et de la vall�e, on doit se convaincre que les eaux ne l'ont point corrod�e lentement, mais qu'elles l'ont entrouverte et emport�e par un effort violent et subit. Or � quelle cause peut-on mieux attribuer le mouvement rapide et le choc qui dut les agiter, qu'� la chute instantan�e de plusieurs milliers de toises cubes de rocher. Je me repr�sente alors ce lac paisible et �lev� chang� en une mer courrouc�e, ses eaux boulevers�es jusqu'au fond de ses ab�mes jaillir au-dessus des sommets voisins, et retombant sur elles m�mes �branler de leur poids et de leur chute la barri�re qui les retenoit, cette barri�re trop foible enfin renvers�e et ses d�bris transport�s au loin.

�M. d'Arcet, dans son discours sur les Pyr�n�es, a pr�sag� la m�me r�volution pour le lac d'Escoubons le plus consid�rable de ceux qui dominent les bains de Bar�ges, et on ne peut douter que si quelqu'�boulement consid�rable vient h�ter et accro�tre l'effet de cette d�b�cle in�vitable, ces r�gions �lev�es subiront un nouveau d�luge dont les hommes et les troupeaux seront la victime, qui ensevelira plusieurs villages, et inondera les tani�res des b�tes fauves.�

M. Reboul has here imagined to himself the former existence of an immense deep lake, which, no doubt, is a thing that may have been, like many others which actually exist. But then he likewise supposes a particular revolution of things, in which one side of that stony circuit, forming the bason of the lake, had been destroyed while the water was discharged. It is this last hypothesis which appears to me to be a thing altogether inadmissible, according to the natural order of things.

In order to see this, it must be considered, that the side of the bason, which has disappeared, must have been either of similar materials to those which we see now remaining, or it must be supposed as composed of loose materials, such as had been more soft, or of those that might be easily dissolved and washed away by the water. If this last had been the state of things, there would not have been occasion for any violent catastrophe, as M. Reboul has supposed; the natural overflowing of the lake had been sufficient to wear the mound by which the water had been detained, and to carry away those materials so as one side might disappear. If, again, this mound had been formed of rock, like what remains of those mountains, in that case, the catastrophe, which this author has suggested as the cause of that destruction, would have been ineffectual to procure that end; for, though such a d�bacle might have carried away a great mass of loose materials, it could not have moved a mound of solid rock.

That of which we have here undoubted information, and that which I am labouring to generalise by comparing similar phenomena, such as are to be found over all the earth, is this, That the natural operations of the atmospheric elements decompose the solid rocks, break down the consolidated strata, waste and wash away those loosened materials of the mountains, and thus excavate the valleys, as the channels by which an indefinite quantity of materials are to be transported to the sea for the construction of future continents. It is this operation of nature which we see performed, more or less, every day, which some natural philosophers have such difficulty in admitting at all, and which others overlook in seeking for some wonderful operation to produce the effect in a shorter time. The prodigious waste that evidently appears, in many places, to have been made of the solid land, and the almost imperceptible effects of the present agents which appear, have given, occasion to those different opinions concerning that which has already happened, or that natural history by which we are to learn the system of this world. The object which I have in view, is to show, first, that the natural operations of the earth, continued in a sufficient space of time, would be adequate to the effects which we observe; and, secondly, that it is necessary, in the system of this world, that these wasting operations of the land should be extremely slow. In that case, those different opinions would be reconciled in one which would explain, at the same time, the apparent permanency of this surface on which we dwell, and the great changes that appear to have been already made.

Now if, in the indefinite course of time, (which we cannot refuse to nature, and which is only to be traced in those effects), the chymical and mechanical operations of the surface are capable of diminishing the mass of land above the level of the sea, (of which fact the appearances here so well described by M. Reboul, and those which are every where else to be observed, leave no room to doubt); and, if the wise system, of a world sustaining plants and animals, requires the long continuance of a continent above the surface of the sea, What reason have we to look out for any other causes, besides those which naturally arise from that constitution of things? And, Why refuse to see, in this constitution of things, that wisdom of contrivance, that bountiful provision, which is so evident, whether we look up into the great expanse of boundless space, where luminous bodies without number are placed, and where, in all probability, still more numerous bodies are perpetually moving and illuminated for some great end; or whether we turn our prospect towards ourselves, and see the exquisite mechanism and active powers of things, growing from a state apparently of non-existence, decaying from their state of natural perfection, and renovating their existence in a succession of similar beings to which we see no end.

We have been comparing similar operations of nature in different countries; but at present we have something farther in our view than to compare the distant regions of the earth. We want to see if it be the same system that is observed in the higher regions of the globe as in the lower. We shall thus have investigated the subject as far as we can go.

The high region of the Andes and Cordeliers affords an opportunity of deciding that question. It is there that we find a habitable country raised above the rest of the earth. It is there that nature, in elevating land, has proceeded upon a larger scale. Here, therefore, in the operations of water upon the surface of the earth, we are to look for effects proportioned to the cause.

Let us cast our eye upon the southern continent of the new world; there is not, from the one end to the other, any great river that flows to the sea upon the west side. A ridge of mountains, at no great distance from the coast, divides the water of this continent; a small part runs to the west; the most part runs to the east; and forms a country which, for fertile plains and navigable rivers, has not its equal upon the globe.

But let us observe the course of the rivers; while confined by the ridges of the Andes and Cordeliers; they run either south or north, and are thus for some time constrained to take a course very different from that which they are afterwards to pursue. It is while thus retained within the ridges of the Andes that those rivers water plains which they had formed; and it is here that we find countries so much elevated above the rest of the world, that, under the direct rays of the sun, their inhabitants are made to suffer from the cold.

It is the collection of those waters running from south to north, and descending from an enormous height, that have formed in the plain those appearances that struck so much the French philosopher, as to make him give us a detail, which, though out of his line, is extremely interesting in the natural history of the earth.

It is in the valley of the Madelena that M. Bouguer found those grand relicts of the wasted strata; but we are now to take a view of a country situated high above the level of that valley. It is that of Santa F�e de Bogota; a fertile plain estimated at 1600 toises, almost about two miles above the level of the sea; and which pours its water into the valley of the Madelena about a degree above Honda, which is mentioned by M. Bouguer as giving so fine an example of those water-worn rocks. The extreme singularity in the situation of this country, and at the same time the perfect similarity which is here to be observed of this country with all the rest of the earth, as the work of water, will excuse my transcribing from M. le Blond, (Journal de Physique, Mai 1786) what I judge to be interesting to my readers.

�Si un observateur attentif parcourt les plaines immenses de l'Am�rique m�ridionale, s'il monte les fleuves rapides et profonds qui les traversent, et les inondent, et s'il franchit les montagnes prodigieuses que l'action des eaux d�truit, il apercevra bient�t qu'un d�veloppement successif et in�vitable de ce nouveau continent tend � l'agrandir dans tous les sens, et rendra peut-�tre un jour sa surface �gale � celle de notre h�misph�re.

�Il est des sites dans les montagnes des Cordill�res ou des obstacles plus ou moins puissant retardent cette m�me d�gradation: la plaine de Santa F�e de Bogota est entre ces sites celui qui m'a paru le mieux caract�ris� et le plus frappant. Il sera l'objet de ce Memoire: on verra avec surprise qu'un pays sain, agr�able, abondant, et fertile aujourd'hui, �toit autrefois le plus d�pourvu et le plus mis�rable du monde, ou l'Indien malheureux n'avoit pour tout bien que des rivieres sans poissons, des oiseaux en petit nombre, un quadrup�de ou deux, et quelques l�gumes; on sera �tonn� d'apprendre qu'une temperature froide environn�e d'un climat br�lant, fut une barri�re insurmontable pour presque tous les animaux et les plantes des pays chauds. La nature agresse et avare de ses dons sembloit en rejeter l'homme, et vouloir y �tre en quelque sorte s�par�e du reste du monde par des rochers �normes, coup�s verticalement, qu'on ne parvient � franchir qu'avec des difficult�s �tranges � travers un brouillard humide et t�n�breux, qui persuade au voyageur fatigu� qu'il travers la r�gion des nues.

�Arriv� au haut de ces montagnes, un nouveau ciel, un nouvel ordre de choses se pr�sentent; ce ne sont plus ces insectes dego�tans et insupportables qui le fatiguoient sans rel�che; ces reptiles venimeux, dont il redoutoit la morsure; ces b�tes f�roces toujours pr�ts � le d�vorer; enfin, cette, chaleur suffocante des lieux bas qu'il vient de quitter; l'air qu'il respire rafra�chit et le vivifie; il s'arr�te, et ce qui l'environne l'�tonn� et le ravit; s'il regarde au-dessous de lui, tout est �clips� par des nuages, dont la surface �gale mouvante lui repr�sente une mer qu'habite le silence et que termine son horison; s'il jette la vue sur la plaine qui se perd devant lui, les nues qu'il croyait sous ses pieds, roulent majestueusement sur sa t�te; de nouvelles montagnes s'�l�vent de toutes parts, et forment un nouveau monde qui paro�t ind�pendant du premier.

�Pour donner une id�e exacte de ce pays singulier, j'ai cru devoir transporter le spectateur � la capitale, o� de l� comme d'un centre, il p�t observer plus commod�ment les ph�nom�nes que j'ai � lui presenter.

�La ville de Santa F�e de Bogota, capital du nouveau royaume de Grenade, a environ 4 degr�s de latitude N. et 304 de longitude, prise de l'�le de Fer, est situ�e au pied et sur le penchant d'une montagne escarp�e qui la couvre � l'est; elle domine une plaine de douze lieues de largeur sur une longueur ind�termin�e et tr�s consid�rable, qui pr�sente toute l'ann�e le riant tableau des plus belles campagnes de l'Europe: les coteaux toujours verts o� les troupeaux bondissent, les prairies couverts de b�tail, les champs bien cultiv�s, les maisons de campagne agr�ables, les hameaux, les villages, les vergers, les jardins, montrent � la fois, les fleurs du printemps et les fruits de l'automne, que l'abondance des pluies ou les s�cheresses retardent ou avancent quelquefois mais dont l'�ternelle dur�e bien loin d'inspirer le plaisir, et d'offrir l'attrait piquant de la nouveaut� qui fait le charme de ces saisons dans nos climats, am�ne bient�t l'indiff�rence pour une beaut� toujours le m�me, pour des agr�mens qui ne changent pas.

�Ce climat est d'ailleurs si �trange et tellement constitu�, que quand on est au soleil, on se trouve bient�t incommod� de sa chaleur; est on � l'ombre? on se sent p�n�tr� d'un air subtil et froid qui transit.

�A trois lieues �-peu-pr�s � l'ouest de la ville, passe la rivi�re de Bogota qui, apr�s avoir re�u les eaux de toute la plaine, la rivi�re de Serrefuela et les torrens qui se pr�cipitent de la cha�ne de montagnes, dirige son cours paisible vers Tekendama � sept ou huit lieues au sud-est �-peu-pr�s; c'est-l� que ces eaux rassembl�es coulent entre une suite de rochers granitiques, dont le plain inclin� acc�l�re leurs vitesse; elles n'offrent bient�t plus qu'un courant rapide, �troit et profond qui, au moment de sa ch�te, rejaillit sur un rocher plac� plus bas que son lit, d'o� il tombe dans une ab�me dont on n'a pu jusqu'ici mesurer la profondeur; c'est la cataracte ou saut de T�kendama.

�Des trous pratiqu�s dans le roc par les anciens aux endroits les plus commodes pour voir toute l'�tendue de cette ch�te prodigieuse, donnent le moyen d'observer sans risque la continuation des rochers qui s'avancent � droite et � gauche et annoncent par leurs hauteur qu'avant le passage que les eaux semblent avoir forc�, la plain de Santa F�e n'�toit alors qu'un lac d'une tr�s-grand �tendue: une tradition constante du pay, mais peu vraisemblable, porte que les Indiens ont creus� cette esp�ce de canal.

�Il y a quelques-uns de ces trous d'o� l'on voit confus�ment le lieu o� finit cette ch�te d'eau effroyable; la rivi�re qui en provient n'offre plus qu'un foible ruisseau, dont le cours presqu'insensible se perd parmi les plantes qui croissent sur ses bords; ainsi disparoissent dans l'�loignement les masses les plus �normes: quelques esp�ces de perroquets et d'autres oiseaux de pays chauds, qui habite cette vall�e profonde et inabordable de ce c�t�, s'�l�vent assez quelquefois pour pouvoir �tre remarqu�s d'en-haut; mais le froid subit de ces montagnes qu'ils craignent, est une obstacle invincible qu'ils ne franchissent jamais: pour jouir commod�ment de ce point de vue, � la fois admirable et effrayant, il faut choisir un jour calme et serein, entre sept � huit heures du matin.

�Il est necessaire de prendre un long d�tour et cheminer pendant toute une journ�e, presque toujours � travers des rochers et des pr�cipices, pour parvenir au pied de cette cataracte; on est alors �trangement surpris de voir que cette rivi�re � peine sensible d'en haut, soit encore un torrent prodigieux, dont la chute en cascades dans une angle de 45 degr�s, offre pendant l'espace d'une grande demie lieue des amas de rochers entass�s au hazard, que frappe et d�truit sans rel�che le plus bruyant conflict des eaux; c'est apr�s cet espace que le courant, devenu plus paisible permet encore de comparer la rivi�re de Bogota � ce qu'est la Seine dans l'�t�.

�Un ph�nom�ne bien extraordinaire et qui sert en m�me tems � donner la plus haute id�e de l'�tendue prodigieuse de cette cataracte, c'est que sa chute commence dans un pays tr�s-froid o� il g�le souvent pendant la nuit, et finit dans un autre o� la chaleur, �gale � nos beaux jours d'�t�, offre la v�g�tation prompte et facile de toutes les plantes des pays chauds: seroit-ce le passage subit de l'air du chaud au froid qui occasionneroit ces gel�es blanches, �-peu-pr�s comme celles qui ont lieu dans nos climats aux approche de l'hiver et � l'entr�e du printemps? car on en �prouve rarement dans la plane.

�Une autre particularit� remarquable de ce pays, c'est le d�faut de poisson dans toutes les rivi�res qui l'arrosent: on en trouve cependant dans celle de Bogota o� les autres rivi�res viennent se rendre; mais c'est une seule esp�ce tr�s-peu abondante, que les Espagnols appellent el Capitan, ou le capitaine; la plus grande longueur de ce poisson est d'environ un pied, sur six pouces de grosseur; il vit dans les eaux troubles et vaseuses de cette rivi�re, et jamais dans les eaux claires; il est gras et excellent � manger: son genre est celui de la mustelle fluviatile de France et le Gades de Linn�.

�Il est certain cependant que les poissons de toutes les sortes abondent dans les grandes rivi�res de l'Am�rique m�ridionale et notamment dans celle de la Magdelaine; ne pourroit-on pas supposer d'apr�s cela, que puisque toute communication des eaux de tout le pays �lev� de Santa F�e est interrompue avec cette derni�re par le saut de Tekendama, ces m�mes eaux n'ont pu en �tre peupl�es comme celle-ci paroissent avoir �t�, au moins en partie, par la mer. Ce m�me d�faut de poisson se remarque dans la plus part de lacs et des rivi�res des Cordill�res, probablement par une cause semblable; il n'y en a point dans les deux lacs assez �tendus qui sont pr�s de la ville d'Hyvarra dans la province de Quito, non plus que dans les rivi�res de la province de Pastos.

�On peut objecter qu'une temperature toujours froide comme celle de Santa F�e, joint � la limpidit� et la rapidit� des torrens des Cordill�res, suffisent pour �carter les poissons, de m�me que cela arrive dans plusieurs rivi�res de l'Europe.

�Cette objection seroit vraie pour la plupart des torrens des Cordill�res, mais on observera que la rivi�re de Bogota quoique froide, est presque stagnante dans bien des endroits, et coule toujours sur de la vase qui en rend les eaux bourbeuses; il est � pr�sumer que, s'il �toit possible d'y tranporter des poissons de nos rivi�res, ils y r�ussiroient aussi bien que les autres productions de l'Europe qui se sont naturalis�es dans ce pays. Quant � la temp�rature constante froide de ces eaux, qui pourroient paro�tre s'opposer au d�veloppement des oeufs du poisson qui habite les rivi�res des pays chauds, on y respondra par le fait suivant.

�A vingt lieues environ au nord de Santa F�e � la m�me �l�vation et � la m�me temp�rature, est un grand lac o� l'on trouve des �les habit�es, et qui en a paru assez grand pour �tre indiqu� dans les cartes g�ographiques, si on en savoit les dimensions; c'est le lac de Chiquinquira assez poissonneux pour y faire des p�ches abondantes, parce que la rivi�re qui en sort n'est pas interrompue par des sauts dans son cours jusqu'� la rivi�re de la Magdelaine; cependant les esp�ces de poissons qu'on trouve dans ce lac ne sont pas aussi vari�es que dans cette grande rivi�re, sans doute � cause de la rapidit� du courant, que le poisson ne remonte pas �galement bien.

�Lorsqu'on gravit sur les montagnes escarp�es qui dominent la ville de Santa-F�e, on ne rencontre, depuis leur base jusqu'� leurs sommets, termin�s par des rochers de granit�, que des bruy�re, des foug�res, quelques plantes sauvages, etc. et pas un arbre qu'on puisse seulement appeler un boisson except� dans quelques gorges � l'abri de courans d'air, o� l'on en voit quelques-uns dont les plus grands, n'�gale pas nos pruni�res; cette v�g�tation engourdie para�t �tre due au froid vif et continuel qu'il fait sur ces montagnes; car plus on monte, moins elle se d�veloppe, et enfin finit par cesser tout-�-fait: on remarque � la moiti� de la hauteur d'une de ces montagnes (� une demi-lieue � peu-pr�s de la ville) une mine de charbon de terre en filon que renferme une rocher entrouvert, dans une situation verticale[27], les torrens y roulent de l'or.�

[Footnote 27: Here is an evidence that those vertical strata, now elevated into the highest stations upon the earth; had been formed originally of the spoils of the land, and deposited at the bottom of the sea.]

�Si l'on descend dans la plaine, si l'on remonte sur les collines, toutes �-peu-pr�s de la m�me hauteur qui sont enti�rement s�par�es des montagnes voisines, et situ�es dans la direction ou courant des rivi�res, on remarque ais�ment qu'elle sont les restes d'une plaine ant�rieure que les eaux ont d�grad�e. Au lieu de ces for�ts, et de ces boissons qui surchargent bient�t nos campagnes lorsque la main de l'homme cesse de les cultiver, un gazon touffu couvre la plaine et les collines de Santa-F�e d'une verdure agr�able sans nul arbrisseau qui puisse en alt�rer l'uniformit�, o� les gramin�e, le plantain, le scor�onnaire, le tr�fle, le marrube, la pimprenelle, le pourpier, la patience, le chardon, le raifort, le cresson, la chicor�e sauvage, la jonquille, la marguerite, le fraisier, la violette, le serpolet, le thym, et mille autres plantes d'Europe et particuli�res � ce pays, offrent les vari�t�s les plus piquantes par la beaut� des fleurs et I'odeur de leurs parfums; des rochers qu'entourent le rosier ou la ronce, et quelques cavernes que le hazard presente sur ces m�mes collines, en rendent l'aspect pittoresque et d�licieux.�

Here is a picture of a country such as we might find in Europe; only it is placed under the line, and elevated above the highest of the frozen summits of the European Alps. We may observe that the same order of things obtains here as in every other place upon the surface of this earth; mountains going into decay; plains formed below from the ruins of the mountains; these plains ruined again, and hills formed in their place; rivers wearing rocks and breaking through the obstacles which had before detained their waters; and a gradual progress of soil from the summits of the continent to the border at the sea, over the fertile surface of the land, successively destroyed and successively renewed.

Here are to be observed two states of country along side of each other, the plain of the Bogota, and the Valley of the Madalena. The courses of the two rivers show the direction of those ridges of mountains which had been raised from the deep; they run south and north, as do those valleys which they drain. At this place we find the valley of the river Cauca, and the valley of the Magdalena parallel to each other, and also to this high plain of the Bogota. Now the waters of this high country, instead of running northward to the sea, as do those of the two valleys below, run both from the south and north until, uniting together, they proceed westward, break the rampard of granite rocks at Tekendama, and fall at once from the high plain down into the valley of the Madalena. Those water formed plains which we perceive subsisting at unequal levels immediately adjoining to each other, while they present us with a view of the degradation of the elevated earth, at the same time illustrate the indefinite duration of a continent; for, we judge not of the progress of things from the actual operations of the surface, which are too slow for the life of man, and too vague for the subject of his history, but from the state of things which we contemplate with a scientific eye, and from the nature of things which we know to be in rule.

In like manner the horizontal situation of the solid strata in the mountains of that low country, while those of the high country are more or less inclined, afford the most instructive view of the internal operations of the globe, by which the Andes had been raised from the bottom of the sea, and of the external operations of the earth by which mountains are formed by the wasting of the elevated surface.

With this description of those high plains upon the north side of the line, let us compare what D. Ulloa has said upon the same subject in describing the continuation of that high country to the south. I shall give it from the best French translation.

It is after describing a cut or narrow ravine in the solid rock with perpendicular sides, about forty yards deep, in which a rivulet runs and the road passes.

�Cette excavation est, en petit, une mod�le des vastes Quebradas ou profondeurs, et fait comprendre leur origine: elles ne pouvoient �tre que semblables � celle-ci: tout s'y est pass� de m�me, ou plus t�t ou plus tard. Les flancs en ont �t� plus ou moins perpendiculaires, jusqu'au moment o� ils se sont affaiss�es, et ont form� des plains inclin�s, lorsque l'eau faisant de plus profondes excavations, eut min� la base qui les soutenoit. Ne pouvant plus alors pers�v�rer dans leur premier �tat, les terrains ont croul�, et ont pris l'inclinaison qu'ils ont conserv�e depuis. La m�me chose arrivera n�cessairement � ce passage de Cona�ca lorsqu'avec le laps du tems, les effets des pluies, de gel�es, des rayons solaires, auront fait tomber en ruine ces parois, quoique de roche rive; car ses agens puissans font sentir leur �nergie aux corps les plus durs. Ainsi les bords du Chapilancas perdront insensiblement la r�gularit� de leur distance, de leurs c�t�s rentrans et saillans, apr�s l'avoir peut-�tre conserv�e plus long tems que d'autres excavations, parce que c'est une pierre dure, qui n'est m�l�e d'aucune veine de terre movible. Nous pouvons le croire sans h�siter; car ce n'est que le seul frottement de l'eau qui a excav� ce lit jusqu'� la profondeur qu'il a. Mais le tems, qui r�duit les roches les plus dures en sablon, ira toujours en �largissant la partie inf�rieure, par son action continuelle et insensible: aussi voit-on ce ruisseau rouler de petites pierres qui se d�tachent sous les eaux, comme on en apper�oit dans la plaine o� il les entra�ne, en sortant de la montagne, pour se d�charger dans une terrain plus spatieux.

�Que ce canal ait �t� excav� � cette profondeur par l'effet continuel du frottement des eaux, ou qu'il a �t� ouvert par une secousse de tremblement de terre qui fit fendre la montaigne, de sorte que le ruisseau qui couloit d'un autre c�t�, se soit jett� de celui-ci. il est certain que cette ouverture profonde est post�rieure � l'arrangement que les terrains eurent apr�s le d�luge; et que c'est ainsi que ces �normes Quebradas de la partie m�ridionale de l'Am�rique, se sont form�es avec le tems, par le frottement du cours rapide des eaux. En effet, on observe que la force avec laquelle s'�coulent toutes les eaux de cette partie du globe, suffit pour arracher des roches d'une masse extraordinaire. C'est pourquoi l'on voit en certaines parages des marques �videntes de leurs excavations profondes au milieu m�me des lits de ces eaux. Ce sont des cubes d'une grandeur �norme, qui n'ont pu �tre d�tach�s avec la m�me facilit� que les parties contigu�s. La rivi�re d'Iscutbaca, qui coule pr�s d'une hameau de m�me nom, nous pr�sente dans son lit une de ces masses, dont la forme est pr�cis�ment celle d'une cube. Lorsque l'eau est basse, ce cube s'�l�ve � sept ou huit varas au-dessus du courant: chaque c�t� porte douze varas de face. Mais ces masses, et autres moindres de diff�rentes formes, qui se voient dans les eaux, ne peuvent �tre arriv�es � cet �tat, sans que l'eau les ait d�garnies peu-�-peu des pierres, des sables que les envelopoient, et qu'elle a arrach�s de tous c�t�s pour les laisser isol�es; or elles se maintiendrons dans cette position, jusqu'� ce que les eaux, cavant de plus en plus, rencontrent enfin � la base des veines de mati�res friables et dissolubles, qu'elles p�n�treront et qu'elles emporteront, en d�truisant l'assiette sur laquelle posent ces masses jusqu'alors inamovibles. Une crue d'eau consid�rable, et qui ne laissera plus paro�tre qu'une varas de cette masse, pourra dans ce tems-l� l'arracher, et la faire rouler; mais ce mouvement, et les chocs qu'elle �prouvera de la part d'autres masses moins grosses, suffiront pour en briser les parties saillantes, et la r�duire en parties moins volumineuses, qui rouleront avec plus de facilit�; et qui par cette seul cause diminueront encore. C'est � cette cause qu'on doit attribuer ces quantit�s prodigieuses de pierres r�pandues �a et l� sur les bords de ces eaux, de m�me que ces roches enormes qu'on y voit d�tach�es, et que jamais les forces humaines n'auroient pu mettre en mouvement.

�Mais pour donner une id�e quelconque de la profondeur de ces excavations, relativement au terrain ou au sol habitable de la partie haute de l'Am�rique, il est � propos de rapporter quelques exp�riences.

�Guancavelica est une bourgade, ou un corps municipal, situ� dans une de ces profondeurs, form�es par diff�rentes suites d'�minences. Le mercure du barom�tre y descend, et s'arr�te � dix-huit pouces une ligne et demie. Sa plus grande variation y est de 1-1/4 � 1-3/4. Sa hauteur est donc de 1949 toises, ou 4536-2/3 varas au-dessus du niveau de la mer. Au haut du mont o� se trouve la mine de mercure, mont qui est habitable par-tout, et qui est imm�diatement surmont� par d'autres, autant qu'il s'�l�ve au-dessus de Guancavelica, le mercure descend et s'arr�te � 16 pouces 6 lignes. Sa hauteur est donc de 2337-2/3 toises, ou de 5448 varas au-dessus du niveau de la mer. Ainsi les eaux ont encore fait cet autre excavation comme il est facile de le voir par des indices manifestes. On remarque en effet dans la partie voisine de leur lit, des roches d�tach�es, toutes semblables � celles qui sont au milieu des eaux; ce qui prouve que les eaux ont �t� au m�me niveau � une �poque beaucoup plus ancienne, et qu'elles ont excav� le sol, a force d'en arracher les parties agr�g�es.

�Ces terrains sont couverts par un si grand nombre de courans, qu'il n'en est aucun ou l'on n'en aper�oive, soit dans des ravins, soit entre des montagnes. J'ai observ� que la superficie des terrains qui en avoisine les lits, est plus unie aux confluens, o� plusieurs de ces courans se r�unissent. Cela vient de ce que l'�minence, qui se trouve au confluent, paro�t avoir �t� diminu�e � la partie o� elle a du former une pointe saillante, � mesure que les eaux l'ont rong�e de l'un ou de l'autres c�t�, en continuant leurs excavation. Ces surfaces planes sont comme par �tages, les unes plus hautes que les autres, et se sont insensiblement form�es, selon que l'eau s'est plus ou moins arr�t�e � diff�rente hauteur, pendent qu'elle creusoit ces lits. On observe, au contraire, que les bords �lev�s dans ces courans, n'ont presque point de largeur dans les endroits o� l'eau a pu suivre son cours tr�s-directement. C'est cependant sur ces bords �troits et escarp�es que se trouvent pratiqu�s les chemins par o� l'on passe. Le danger y est tr�s grand: car � peine un animal peut-il poser le pied. Toutes les fois que le courant fait un d�tour, la surface des bords a plus de largeur; cependant moins que lorsque plusieurs se r�unissent. Un voit facilement pourquoi. L'eau forc�e de se d�tourner, s'�loigne plus de la rive que quand elle va en ligne droite, et ronge ainsi le c�t� saillant sur lequel elle fait son d�tour, et qui en devient comme le centre.

�On peut conclure de ce que je viens de dire, � quelle �l�vation est la partie haute ou montagneuse de l'Am�rique, relativement � la partie basse, et qu'il y a des excavations extr�mement profondes; car elles ont, comme je l'ai d�j� dit, 1769-2/3 varas perpendiculaires, ou m�me d'avantages: cependant elles ont assez de surface pour devenir le local de nombre d'habitations fort peupl�es, qui en tirent tous les produits n�cessaires � la vie. Parmi ces Quebradas, il en est de plus �tendues ou de moins profondes que les autres. Or, c'est en ceci que cette partie du monde se distingue de toutes les autres.

�Mais il est indiff�rent pour mes vues que ces vastes ouvertures soient l'effet des courans d'eau, ou de toute autre cause. Ce que je me propose, est uniquement de montrer qu'elles sont d'autant plus profondes et plus vastes, que ces terrains sont immens�ment hauts.�

M. Monnet considers the natural operations of water, upon the surface of the earth, as truly forming the shape of that surface; but he draws some very different conclusions from those which I have formed. It is in his Nouveau Voyage Min�ralogique, fait dans cette partie du Hainault connue sou le nom de Thi�rache. Journal de Physique, Aoust 1784.

�Il ne faut pas s'attendre � trouver dans ce pays des hautes montagnes qui frappent la vue de loin; c'est seulement un pays dont l'�l�vation est g�n�rale sur tout ce qui l'entoure, et est coup� profond�ment par des vall�es ou ravin, ouvrage des eaux, qui, la comme ailleurs, ont use et coup� peu-�-peu les terrains et les roches les plus dures, pour s'ouvrir un passage; et peut-�tre pourroit-on dire; si la diminution des eaux n'�toit pas trop sensible, qu'un jour ce pays offrira des montagnes hautes est escarp�es comme tant d'autres, apr�s que les eaux auront creus�, pendant des milliers de si�cles, ses gorges, ses ravins, et diminu� la largeur des masses de terrain qui sont entr'eux.

�Quant � present, on ne peut y voir que de petites montagnes, ou plut�t des bosses de terre, avec des platures plus ou moins consid�rables � leurs sommets, avec de c�t�s coup�es plus ou moins obliquement, ou plus ou moins droites. Ce qu'on y trouve de singulier c'est que ces petites montagnes sont presque toutes plus basses que les plaines qui les avoisinent, encore ne sont elles que dans la partie calcaire.

�La plus profonde tranch�e de ce pays est, sans contredit, celle ou coule la Meuse, qui, malgr� la duret� des roches d'ardoise et de quartz au travers desquelles elle passe, a coup� le terrain depuis Charleville jusqu'� Givet, � une tr�s-grande profondeur. Dans cette distance, on voit presque par-tout les c�t�s coup�es presque � pic sur la rivi�re, de deux � trois cents pieds de hauteur perpendiculaire; et comme c'est une r�gle g�n�rale, que plus les c�t�s sont coup�es droites, moins elles sont distantes l'une de l'autre, on con�oit que le canal de la Meuse, dans cette �tendue de terrain, doit �tre fort �troit, eut �gard � beaucoup d'autres o� il coule un bien moindre volume d'eau. Cela n'emp�che pas qu'on n'y aper�oive des marques de la r�gle g�n�ral que fait l'eau, et n'y ait taill� des angles saillans et des angles rentrans, qui sont tr�s-grands en certains endroits. Nous verrons que Revin et Fumai, deux lieux principaux des bords de la Meuse, sont situ�s sur deux de plus grandes de ces ouvertures o� se trouvent des platures assez vaste pour permettre, outre un emplacement consid�rable pour les maisons, l'�tablissement de beaucoup de jardins, et m�me des pi�ces � grain et des prairies. Aussi, quand on arrive sur la tranch�e de la Meuse, les lieux et les terrains cultiv�s qu'on voit dans son fond, paroissent comme s�par�s sous les autres et comme dans un autre pays.

�Les autres coupures ou ravins de ce pays, quoique moins profonds, offrent cependant cette singularit�, remarqu�e d�j� ailleurs, que leurs grandeurs et profondeur ne sont point du tout proportionn�es au volume de l'eau qui y coule.

�Le massif sur lequel est situ� Beaumont, est coup� presque perpendiculairement � l'ouest, sud-ouest et cette coupe en fait de ce c�t�-l� un rempart inaccessibles, ayant plus de 100 pieds de hauteur. Quand j'ai consid�r� cette grande coupe, et le d�tour que fait la petite rivi�re qui coule au bas de ce massif, je n'ai pus me refuser � croire qu'il n'y avoit en l� un bien plus grande courant d'eau, qui a battu et min� ce massif, en s'y brisant avec force; car on ne peut supposer, avec quelque vraisemblance, que cet ouvrage ait �t� fait par le volume d'eau qui y coule actuellement: et il ne faut pas s'�tonner de ce disparate; par-tout vous le trouverez; ce qui d�montre �videmment que la quantit� d'eau diminue insensiblement, et que la partie solide de notre globe augmente � proportion que la partie liquide diminue; et s'il faut encore �tendre ce principe, j'ajouterai, que par-tout vous verrez les bornes de la mer et des rivi�res recul�es; par-tout vous trouverez d'anciens courans d'eau dess�ch�s, et m�me des rivi�res consid�rables, � en juger par les collines ondul�es qu'on voit encore. Mais cette partie essentielle de la min�ralogie qui est effrayante par les cons�quences qu'elle presente, et qui peut influer sur le syst�me g�n�ral du monde, sera �tendue un jour dans un autre memoire, o� je d�crirai d'anciens cours de rivi�res de la France, qui n'existent plus. J'esp�re fair voir alors, appuy� par les faits que me fournira l'histoire, que les rivi�res et les fleuves actuels ont �t� plus volumineux qu'ils ne le sont maintenant, et qu'il existoit en France un grande nombre de vastes lacs, comme dans l'Am�rique Septentrionale, et dont � peine il nous reste des traces aujourd-hui.�

This opinion of M. Monnet, concerning the diminution of water upon the earth, does not follow necessarily from those appearances which he has mentioned. The surface of the earth is certainly changed by the gradual operations of the running water, and it may not be unfrequent, perhaps, to find a small stream of water in places where a greater stream had formerly run; this will naturally happen upon many occasions, as well as the opposite, by the changes which are produced upon the form of the surface. Likewise the conversion of lakes into plains is a natural operation of the globe, or a consequence of the degradation of the elevated surface of the earth, without there being any reason to suppose that the general quantity of running water upon the land diminishes, or that the boundaries of the various seas are suffering any permanent removal.

Whether we examine the Alps in the Old World, or the Andes in the New, we always find the evidence of this proposition, That the exposed parts of the solid earth are decaying and degraded; that these materials are hauled from the heights to be travelled by the waters over the surface of the earth; and that the surface of the earth is perpetually changing, in having materials moved from one place and deposited in another. But these changes follow rules, which we may investigate; and, by reasoning according to those rules or general laws, upon the present state of things, we may see the operation of those active principles or physical causes in very remote periods of this mundane system, and foresee future changes in the endless progress of time, by which there is, for every particular part, a succession of decay and renovation.

The Chevalier de Dolomieu, in his most indefatigable search after natural history and volcanic productions, has given us the description of some observations which are much calculated to put this subject in a conspicuous point of view. I give them here as examples of the operation of water wasting the land and forming valleys in a system where every thing is tending to the wisest end or purpose; but they are no less interesting as proper to give us a view of the mineral operations of the globe. That therefore which, according to the order of the subject, ought to be cited in another part of this work, is here necessarily mixed in the narrative of this natural historian.

There is, upon this occasion, such a connection of the facts by which the mineral operations of the earth, either consolidating the materials deposited at the bottom of the sea, or elevating land by the power of subterraneous heat, are to be understood, and of those by which the operations of the surface are to be explained, that while they cannot be separated in this narration, they throw mutual light upon each other. It is in his M�moire sur les Volcans �teints du Val di Noto en Sicile. Journal de Physique, Septembre 1784.

�Je trouvai les premiers indices de ces volcans, en allant de Syracuse � Sortino, � une lieue de cette ville, au fond du profond vallon qui y conduit. Quelques morceaux de laves entra�n�s et arrondis par les eaux m'annonc�rent d'avance que j'allois entrer dans un pay volcanique. Mon attention se fixa bient�t apr�s sur un courant de laves que je vis sortir d'une montagne calcaire qui �toit sur ma droite, il �tois coup� par une vallon dont les eaux couloient sur un sol calcaire, et alloit se perdre dans le massif �galement calcaire qui �toit sur ma gauche. Je passai en suite alternativement sur des mati�res calcaires et volcaniques, pour arriver � Sortino, ville baronale b�tie sur une montagne calcaire qui domine la vallon, et qui lui presente des escarpemens de plus de 200 toises d'�l�vation, dans lesquels les banc de pierres dure sont horizontaux, et exactement parall�les.�

Here, it is to be observed, are horizontal beds remaining, which give a measure of what had been abstracted by some cause, which is our present subject of investigation. The Chevalier proceeds:

�Les environs de Sortino m'offrirent des ph�nom�nes et des singularit�s dont l'explication me parut difficile, et qui tinrent pendant longtemps mon esprit en suspens. Je vis d'abord les mati�res volcaniques ensevelies sous des bancs horizontaux de pierres calcaires, tr�s-coquilli�res, contenant sur-tout une infinit� de madr�porites, quelques-uns d'un volume �norme. Je vis ensuite des hauteurs dont les sommets seuls �toient volcaniques, et les noyaux calcaires, sans que les laves qui couronnoient ces sommets eussent communication avec aucun courant, et eussent d'autre �tendue que le plateau qu'elles recouvroient. Ces laves n'avoient pu �tre form�es o� je les voyois; elles �toient venues d'ailleurs; mais d'o� et comment? etc. Je me d�terminai � consulter les montagnes les plus hautes, qui �toient � quelque distance. J'en vis de loin plusieurs dont la forme �toit � peu-pr�s conique, et dont les sommets �toient pointus; elles �toient vers le nord, ou nord-ouest de Sortino, dans la direction de l'Etna, qui terminoit mon horizon, � une distance de 13 ou 14 lieues, etc.

�La montagne Saint-George, une des plus hautes de tout le canton du sommet de laquelle je pouvois prendre une id�e topographique de tous le pays, qui domine tout ce qui entoure, � l'exception de quelques pics calcaires qui lui sont au sud; (tel que celui de la montagne de Boujuan); cette montagne, dis-je, dont la forme est conique, et qui est isol�e par des vall�es, dont le sol lui �toit sur-abaiss� de 3 ou 400 toises, a sa base calcaire. Sur cette premi�re assise repose une couche volcanique, ensuite une autre tranche volcanique calcaire, � laquelle succ�de un sommet form� d'une lave dure. Une autre montagne aupr�s du fief de la Copodia, �galement conique, est toute volcanique, � l'exception d'une couche de pierre calcaire dure et blanche, qui la tranche � moiti� hauteur parall�lement � sa base. Quelques montagnes o� les couches volcaniques ou calcaires sont plus ou moins nombreuses. La montagne de Pimalia est volcanique � sa base et calcaire � son sommet; et enfin la montagne isol�e sur laquelle est b�tie la ville de Carientini est moiti� calcaire et moiti� volcanique: mais ici la division des deux substances se fait par un plan verticale, etc. Apr�s �tre arriv� � cette limite des volcans, dont je poursuivois le foyer, je pris du c�t� de l'est; je suivis jusqu'� Melilli les hauteurs qui accompagnent la vall�e de Lentini, et qui dominent la plaine d'Auguste; et cheminant � mi c�t� je vis d�boucher du milieu des montagnes calcaires, qui, r�unies par leur base, ne forme qu'une m�me groupe, sous le nom de monts Hybleens, Colles Hyblei, plusieurs courans de lave qui se terminent comme s'ils avoient �t� coup�s sans avoir eu le temps de descendre dans la vall�e, et de s'incliner pour en prendre la pente. Plusieurs de ces courans sont cristallis�s en basaltes prismatiques; on en voit de tr�s-belles colonnes au-pr�s de Melilli. Au del� de cette ville jusqu'� Syracuse, on ne voit plus de traces de volcans, et les escarpemens en face du golfe d'Auguste n'offrent qu'un massif calcaire en bancs horizontaux, etc.

�Je revins a Sortino, et en allant visiter l'emplacement de l'ancienne Erbessus, connue maintenant sous le nom de Pentarica, je traversai deux gorges d'une extr�me profondeur, dont les encaissemens, taill�s presque � pic, ont plus de 600 pieds d'�l�vation, etc.�

The Chevalier then found, in the mountain of Santa Venere, an extinct volcano; and proceeds in his Memoir to give some explanation for those appearances, as follows:

�Je ne pus pas douter que cette montagne ne f�t le volcan que je cherchois, et qui avoit r�pandus ses laves � une tr�s-grande distance autour de lui, sur-tout dans la partie de l'est; mais il me restoit � r�soudre le probl�me de la formation des montagnes isol�es et coniques, mi-parties volcaniques et calcaires, qui ne tiennent � aucune courant, et qui sembloient n'avoir aucune relation directe avec mon volcan. L'�tude de la montagne Santa-Venere, et des pays circonvoisins, m'apprit que ce volcan s'�toit �lev� au milieu de la mer qui alors occupoit nos continens, que sa t�te seule s'�toit soulev�e au-dessus du niveau des eaux. Je fus convaincu que, lorsqu'il r�pandoit autour de lui des torrens de mati�res enflamm�es, la mer entassoit des d�p�ts calcaires; que chaque nouvelle �ruption trouvoit un sol plus �lev�, sur lequel elle se r�pandoit; que bient�t les nouvelles mati�res volcaniques �toient ensevelies sous de nouveaux d�p�ts, et qu'ainsi, par l'entassement successif et r�gulier des produit du feu et des d�p�ts de l'eau, s'�toit form� un �norme massif, � sommet aplati et horizontal. Ce massif occupoit tout le centre du Val di Noto, recouvroit de plusieurs centaines de toises le sol sur lequel s'�toit r�pandu les premi�res laves, et fut divis�, morcel� et d�grad� par les courans ou par le ballottement des eaux, lors de la grande d�b�cle du de la catastrophe qui changea l'emplacement des mers. Les vallons et les gorges qui se form�rent au milieu de ce massis, s�par�rent les laves de la montagne � qui elles appartenoient, coup�rent les courans, et fa�onn�rent, avec les d�bris de ce massif des montagnes de toutes les formes, mais la majeure partie conique, ainsi qu'on peut le voir journellement, lorsque, dans un terrain argilleux et submerg� l'eau, se retirant avec pr�cipitation, excave par-tout o� elles trouve moins de resistance, creuse les premiers sillons qu'elle a trac�s et forme des petits c�nes, dont les sommets sont � la hauteur du sol sur lequel reposoient les eaux. Les parties o� les laves avoient coul� successivement dans la m�me direction, les unes au-dessus des autres, ont donn� naissance aux montagnes dans lesquelles les couches volcaniques et calcaires se succ�dent parall�lement. Celles sur lesquelles aucunes laves ne se sont port�es, n'ont produit que des montagnes totalement calcaires que se trouvent entrem�l�es avec les autres. Celles enfin sur lesquelles le hazard ou des circonstances locales out entasse de pr�f�rence, et dans le m�me lieu, les mati�res que vomissoit le volcan, sans laisser le temps au d�p�t des eaux de se m�ler avec elles, ont produit quelques petites montagnes presque enti�rement volcanique, o� les cendres sont agglutin�es par une p�te calcaire, etc. Cette th�orie rend raison de tous le ph�nom�nes et de toutes les singularit�s qui s'observent dans le m�lange des produits du feu et des d�p�ts de l'eau, et une infinit� de preuves de differens genres, mais qui seroient �trang�res � ce Memoire, concourent � d�montrer, l'existence d'un ancien plateau qui �toit �lev� de plusieurs centaines de toises au-dessus du sol actuel des vall�es et du niveau de la mer, qui couvroit non seulement le Val di Noto, mais encore toute la Sicile, et dont les d�bris ont form� toutes les montagnes actuellement existantes, � l'exception de l'Etna.�

It is not the explanation here given by the Chevalier de Dolomieu, of the manner in which this great mass of land was formed in the sea, that is concerned with the subject at present under our examination, but certain facts set forth in the Memoir, and a certain conclusion which is there endeavoured to be drawn from those interesting facts[28]. This will be understood by considering; first, it is on all hands acknowledged, that the stratified matter of the globe was successively deposited in the bottom of the sea; secondly, it is also agreed, that this great mass of Sicily, formed originally under the sea, was afterwards placed in the atmosphere, whether by the retreat of the sea or by the elevation of the land; and now, lastly, we are of one mind with respect to the present shape of things, as having been produced by the wasting away of great part of that mass which had been once continued all over the island, as high at least as the tops of the mountains, i.e. about a mile above the level of the sea; we only differ in the time and agents which have been employed in this Operation.

[Footnote 28: In the first part of this work, the distinction has been made of true volcanic productions, and those which are so frequently confounded with them; these last, though the creatures of subterranean fire, and bodies which have been made to flow in a fluid state, are clearly different from those masses of lava which have issued from a volcano, as has been there described. I would only here observe, that, according to this Theory, these bodies, which the Chevalier de Dolomieu here represented as lava and volcanic production, must be considered as unerupted lavas, which had been made to flow among the strata of the earth, where other at the bottom of the sea, or during those operations by which this land was erected above the level of the ocean.]

On the one hand, the Memoir now before us represents this great effect as belonging to an unknown cause, so far as we are ignorant of that grand d�bacle or catastrophe which changed the situation of the sea. On the other hand, the Theory now proposed explains this operation, of forming those conical mountains of Sicily, and hollowing out its valleys, by known causes, and by employing powers the most necessary, the most constant, and the most general, that act upon the surface of the earth.

But, besides explaining this change of land and water by an unknown cause, our author has here employed, for the removing of this mass of solid rock, powers which appear to me no ways adequate to the end proposed. The running of water upon the soft mud left by a river, given here as an example, corresponds indeed in some respects with the form of valleys; for, water acts upon the same principle, whether it makes a channel through the subtile sediment of a river, or through the travelled materials of a valley. But it is not here that there is any difficulty in conceiving the rivers of Sicily to have shaped the mountains and the valleys; it is in removing the masses of solid rock, which covered the whole surface of this land in successive strata, that any doubt could occur in ascribing the actual appearances of things to the natural operations of the earth; but it is here particularly that the retreat of the sea, in whatever manner supposed to be done, is altogether incompetent for the purpose which is now considered. I flatter myself, that when the Chevalier de Dolomieu, who has employed his uncommon talents in examining and elucidating the effects of fire in the bowels of those burning mountains, shall consider and examine the effects of time upon the surface of the earth, he will be ready to adopt my opinion, that there is no occasion to have recourse to any unknown cause, in explaining appearances which are every where to be found, although not always attended with such remarkable circumstances as those with which his labours have enriched natural history.

It may be proper to give a view of the operations of nature upon the Apennines. It is from an account of a journey into the province of Abruzzo, by Sir William Hamilton. Phil. Trans. 1786.

The road follows the windings of the Garigliano, which is here a beautiful clear trout stream, with a great variety of cascades and water-falls, particularly a double one at Isola, near which place CICERO had a villa; and there are still some remains of it, though converted into a chapel. The valley is extensive, and rich with fruit trees, corn, vines, and olives. Large tracts of land are here and there covered with woods of oak and chestnut, all timber trees of the largest size. The mountains nearest the valley rise gently, and are adorned with either modern castles towns, and villages, or the ruins of ancient ones. The next range of mountains, rising behind these, are covered with pines, larches, and such trees and shrubs as usually abound in a like situation; and above them a third range of mountains and rocks, being the most elevated part of the Apennine, rise much higher, and, being covered with eternal snow, make a beautiful contrast with the rich valley above mentioned; and the snow is at so great a distance as not to give that uncomfortable chill to the air which I have always found in the narrow valleys of the Alps and the Tyrol.

Having thus examined the alpine countries both of the Old World and the New, it remains to observe some river in a more low or level country emptying itself into a sea that does not communicate with the ocean. The Wolga will now serve for this purpose; and we shall take our facts from the observations of those men of science who were employed by their enlightened Sovereign to give the natural as well as the economical history of her dominions.

Russia may be considered as a square plain, containing about 40 degrees of longitude, and 20 of latitude, that is, between the 47� and 67� degrees. The east side is bounded by the Oural mountains, running in a straight line from north to south. The west is bounded by Poland. The south reaches to the Caspian and Black Seas, as does the north to the Polar Ocean.

The greatest part of the water which falls upon this extensive country is delivered into the Caspian by the river Wolga; and this water runs from the east and west sides, gathered in two great rivers, the Kama and the Oka. The water thus gathered from the two opposite extremities of this great kingdom meet in the middle with the Wolga, which receives its water from the north side. We thus find the water of this great plain running in all directions to its centre. Had this been the lowest place, here would have been formed a sea or lake. But this water found a lower place in the bed of the Caspian; and into this bason it has made its way, in forming to itself a channel in the great plain of the Wolga.

Our present purpose is to show that this channel, which the Wolga has cut for itself, had been once a continued mass of solid rock and horizontal strata, which in the course of time has been hollowed out to form a channel for those waters. These waters have been traversing all that plain, and have left protuberances as so many testimonies of what had before existed; for, we here find the horizontal strata cut down and worn away by the rivers.

M. Pallas gives us very good reason to believe that the Caspian Sea had formerly occupied a much greater extent than at present; there are the marks of its ancient banks; and the shells peculiar to the Caspian Sea are found in the soil of that part of its ancient bottom which it has now deserted, and which forms the low saline Steppe. He also makes it extremely probable that the Caspian then communicated with the Euxine or Black Sea, and that the breaking through of the channel from the Euxine into the Mediterranean had occasioned the disjunction of those seas which had been before united, as the surface of the Caspian is lowered by the great evaporation from that sea surrounded with dry deserts.

However that may he, it is plain, that throughout all this great flat inland country of Russia, the solid rocks are decaying and wearing away by the operation of water, as certainly, though perhaps not so rapidly, as in the more mountainous regions of the earth.

If there is so much of the solid parts worn and washed away upon the surface of this earth, as represented in our Theory; and if the rivers have run so long in their present courses, it may perhaps be demanded, Why are not all the lakes filled up with soil; and why have not the Black and Caspian Seas become land or marshy ground, with rivers passing through them to the ocean? Here is a question that may be considered either as being general to all the lakes upon the earth, or as particular to every lake which should thus find a proper explanation in the Theory. With regard to the last of these, the question has already been considered in this view, when the particular case of the Rh�ne was taken as an example; and now we are only to consider the question as general to the globe, or so far as belonging to the Theory, without particularising any one case.

It must be evident, that the objection to the Theory, here supposed to be made, is founded necessarily upon this, that the solid basis of our continent, on whose surface are found the lakes in question, is preserved without change, because, otherwise, the smallest variation in the basis may produce the most sensible effects upon the surface; and in this manner might be produced dry land where there had been a lake, or a lake where none had been before. But, as the present Theory is founded upon no such principle of stability in the basis of our land, no objection, to the wasting operations of the surface of the earth, can be formed against our Theory, from the consideration of those lakes, when the immediate cause of them should not appear.

The natural tendency of the operations of water upon the surface of this earth is to form a system of rivers every where, and to fill up occasional lakes. The system of rivers is executed by wearing and wasting away the surface of the earth; and this, it must be allowed, is perfect or complete, at least so far as consistent with another system, which would also appear to be in nature. This is a system of lakes with which the rivers are properly connected. Now, as there are more way than one by which a lake may be formed, consistent with the Theory, the particular explanation of every lake must be left to the natural history of the place, so far as this shall be found sufficient for the purpose.

There are many places which give certain appearances, from which it is concluded, by most intelligent observators, that there had formerly existed great lakes of fresh water, which had been drained by the discharge of those waters through conduits formed by some natural operation; and those naturalists seem to be disposed to attribute to some great convulsion, rather than to the slow operation of a rivulet, those changes which may be observed upon the surface of the earth. Let us now examine some of those appearances, in order to connect them with that general system of moving water which we have been representing as every where modifying the surface of the earth on which we dwell.

It is the P. Chrysologue De Gy, who gives the following description. Journal de Physique, Avril 1787.

�La principaute de Porrentrui l'emporte encore en ce genre sur le reste du Jura � ce qu'il paro�t. On pourra en juger sur les circonstances locales que je vais rapporter. Une partie de cette principaut� est divis�e en quatre grandes vall�es, d'environs quatre lieues de long, sur trois quarts-d'heure ou une heure de large, s�par�es par autant de cha�nes de montagnes fort �lev�s et large en quelques endroits d'une lieue et demie. Les extr�mit�s de chacune de ces vall�es sont plus �lev�es que le milieu, et on ne peut pas en sortir par ces extr�mit�s sans beaucoup monter. Mais ces vall�es ont des communications entr'elles par une pente assez douce � travers ces masses �normes de montagnes qui les separent, et qui sont coup�es au niveau du milieu des vall�es sur 300, 400, 500 toises de hauteur et dans toute leur largeur. On pourroit assez justement comparer ces vall�es � des berceaux pos�s les uns � c�t� des autres, dont les extr�mit�s, remplies en talus, seroient plus �lev�s que les cot�s, et dont ces c�t�s seroient coup�s jusqu'au fond, pour laisser une passage de l'un � l'autre. Je connois sept � huit passages semblables � travers ces hautes montagnes, dans une quarr� d'environ quatre � cinq lieues; et dont quatre aboutissent � la vall�e de Mouthier-Grand-Val. Ces passages sont �vas�s dans le dessus, d'environ une demi-lieue par endroits; mais leurs parois, en talus, se rejoignent dans le fond o� coule un ruisseau. On a pratiqu� des routes sur quelques-uns de ces talus, mais les roches sont quelquefois si resserr�es et si escarp�es, qu'on a �t� oblig� de construire un canal sur le ruisseau, pour y faire passer la route. C'est-l� que l'on voit � son aise, la nature de ces rochers primitives, leur direction, leur inclinaison, et tous leurs autres accidens qui demanderaient chacun une dissertation particuli�re trop longue pour le moment, et il faut les avoir vues pour se faire une juste id�e des sentimens de grandeur, de surprise, et d'admiration qu'elles inspirent, et que l'on ne peut pas exprimer par des paroles. Cependant, les sources de ruisseaux, ou si l'on veut des rivi�res qui traversent ces montagnes, sont beaucoup plus basses que les sommit�s des montagnes elles-m�mes, ces sources ne font donc pas la cause de ces effets merveilleux. Il a fallu un agent plus puissant pour creuser ces ab�mes.�

M. de la Metherie has taken a very enlightened view of the country of France; and has given us a plan of the different ridges of mountains that may be traced in that kingdom, (Journal de Physique, Janvier 1787). Now there is a double purpose in natural history to which such a plan as this may be applied; viz. first, to trace the nature of the solid parts, on which the soil for vegetation rests; and, secondly, to trace the nature of the soil or cultivated surface of the earth, on which depends the growth of plants.

With regard to the first, we may see here the granite raising up the strata, and bringing them to the light, where they appear on each side of those centrical ridges. What M. de la Metherie calls Monts Secondaires, I would call the proper strata of the globe, whether primary or secondary; and the Monts Granit, I would consider as mineral masses, which truly, or in a certain sense, are secondary, as having been made to invade, in a fluid state, the strata from below, when they were under water; and which masses had served to raise the country above the level of the ocean.

But this is not the subject here immediately under consideration; we are now tracing the operations of rivers upon the surface of the earth, in order to see in the present state of things a former state, and to explain the apparent irregularity of the surface and confusion of the various mineral bodies, by finding order in the works of nature; or a general system of the globe, in which the preservation of the habitable world is consulted.

For this last purpose also the mineral map of M. de la Metherie is valuable. It gives us a plan of the valleys of the great rivers, and their various branches, which, however infinitely ramified, may be considered as forming each one great valley watered, or rather drained, by its proper river. But the view I would now wish to take of those valleys, is that of habitable and fertile countries formed by the attrition of those rivers; and to perceive the operation of water wearing down the softer and less solid parts, while the more hard and solid rocks of the ridges, as well as scattered mountains, had resisted and preserved a higher station.

In this map, for example, let us suppose the first and second ridge of our author's plan to be joined at the mouth of the Loire, and retain the water of that river, as high as the summit of its surrounding ridges; this great valley of the Loire, which at present is so fine and fertile a country, would become a lake; in like manner as the proper valley of the Rh�ne, above St Maurice, would be drowned by shutting up that gap of the mountains through which the Rh�ne passes in order to enter the plain of Geneva.

This is the view that P. Chrysologue takes of those small valleys formed between the ridges of the Jura. But this is not perhaps the just view of the subject; for though by closing the gap by which the Loire or Rh�ne, passes through the inclosing ridge, the present country above would certainly be overflowed by the accumulated waters, yet it is more natural to suppose, that the great gap of the Loire, or the Rh�ne, had been formed gradually, in proportion as the inclosed country had been worn down and transported to the sea. We have but to consider, that the attrition of those transported materials must have been as necessary for the hollowing out of those gaps in the solid rock of the obstructing mountains, as the opening of those gaps may have been for the transporting of those materials to the sea. But it is perhaps impossible, from the present appearance of things, to see what revolutions may have happened to this country in the course of its degradation; what lakes may have been formed; what mountains of softer materials may have been levelled; and what basons of water filled up and obliterated.

This general view of the valley of the Loire, and all its branches, is perhaps too extensive to be admitted in this reasoning from effect to cause; we must approximate it by an intermediate step, which will easily be acknowledged as entering within the rule. It is in Forrez, near the head of the Loire. There we find the plain of Mont Brison, 40,000 toises or 22 miles long and half as wide, surrounded by a ridge of granite mountains on every side. Here the river, which is a small branch of the Loire, enters at the upper end of the plain (as M. de Bournon has described)[29] �Par une gorge tr�s �troite et tortueuse,� and goes out in like manner at the under End.

[Footnote 29: Journal de Physique, Mai 1787.]

Those French philosophers, who have seen this plain, have little doubts of this having been a lake, that is to say, they easily admit of the original continuity of those ridges of mountains in which the gaps are now found, through which the river passes. But upon those principles it must be evident, that the river has hollowed out that plain, at the same time that it had formed the gaps in those ridges of the granite mountains. The only solid part, or original stratum, which M. de Bournon has described as having seen in this plain, is a decomposing gr�s or sandstone; but there is reason to suppose, that there had been both calcareous and argillaceous or marly strata filling the hollow of that space which is inclosed by the granite mountains; consequently, no difficulty in conceiving that the river, which must wear away a passage through those mountains, should also hollow out the softer materials within, and thus form the plain, or rather a succession of plains, in proportion as the level of the water had been lowered with the wearing mountains.

If we are allowed to make this step, which I think can hardly be refused, we may proceed to enlarge our view, by comprehending, first, the Vallais of the Rh�ne, secondly, the countries of the Seine and Rh�ne, above the mountains through which those two rivers in conjunction have broke, below Lyons; and, lastly, that country of the Rh�ne and Durance which is almost inclosed by the surrounding mountains, meeting at the mouth of the Rh�ne. But this reasoning will equally apply to the countries of the Garonne, the Loire, and the Seine.

One observation more may now be made with regard to the courses of great rivers, and the fertile countries which they form in depositing the travelled soil; it is this. That though those rivers have hollowed out their beds and raised their banks; though they are constantly operating in forming fertile soil in one place and destroying it in another; and though, in many particular situations, the fertile countries, formed at the mouths of those rivers, are visibly upon the increase, yet the general progress of those operations is so slow, that human history does not serve to give us information almost of any former state of things. The Nile will serve as an example of this fact.

The river Nile, which rises in the heights of Ethiopia, runs an amazing tract through desert countries, and discharges its waters near the bottom of the Mediterranean sea, fertilizes a long valley among barren countries with which it is surrounded, and thus lays the foundation of a kingdom, which, from its situation and the number of people it can maintain and easily bring together for any manner of action, is perhaps the strongest that can well be imagined. Accordingly, it has been of old a great kingdom, that is to say, a powerful state within itself; and has left monuments of this power, which have long been the admiration of the world. The most ancient Grecian Histories mention these monuments as being no better known, with regard to their dates and authors, than they are at this day.

The conclusion here meant to be drawn is this, that, in a period of time much more ancient than the most ancient periods in human history, Egypt had been a country formed and watered by the Nile in like manner as it is at present; that though continual changes are making in this as well as in every other river, yet, on the whole, no sensible alteration can be discerned within the compass of human experience, consequently, it is only by considering, in a scientific manner, the nature of things, and making allowances for operations which have taken place in time past, that any competent judgment can be formed of the present shape and condition of countries, or of any particular place upon the surface of this earth, so far as regards its date, its causes, or its future state. Nothing, almost, but the kingdom of Egypt would have formed those stupendous monuments of art and labour; and nothing but the present state of Egypt, fertilised by the Nile, could have formed that powerful kingdom which might execute those works.

Thus there is a system of mountains and valleys, of hills and plains, of rivulets and rivers, all of which are so perfectly connected, and so admirably proportioned, in their forms and quantities, like the arteries and veins of the animal body, that it would be absurd to suppose any thing but wisdom could have designed this system of the earth, in delivering water to run from the higher ground; or that any thing could have formed this beautiful disposition of things but the operation of the most steady causes; operations which, in the unlimited succession of time, has brought to our view scenes which seem to us to have been always, or to have been in the original construction of this earth.

To suppose the currents of the ocean to have formed that system of hill and dale, of branching rivers and rivulets, divided almost ad infinitum, which assemble together the water poured at large upon the surface of the earth, in order to nourish a great diversity of animals calculated for that moving element, and which carry back to the sea the superfluity of water, would be to suppose a systematic order in the currents of the ocean, an order which, with as much reason, we might look for, in the wind. The diversity of heights upon the surface of the earth, and of hardness and solidity in the masses of which the land is formed, is doubtless governed by causes proper to the mineral kingdom, and independent either of the atmosphere or sea; but the form and structure by which the surface of the earth is fitted peculiarly to the purpose of this living world, in giving a fertility which sustains both plants and animals, is only caused by those powers which work upon the surface of the earth,--those powers, the operation of which men in general see with indifference every day, sometimes with horror or apprehension.

The system of sustaining plants and animals upon a surface where fertility abounds, and where even the desert has its proper use, is to be perceived from the summit of the mountain to the shore within the region of the sea; and although we have principally taken the Alps, or alpine situations, for particular examples, in illustrating this operation of the waters upon the surface of the earth, it is because the effects are here more obvious to every inquirer, and not because there is here to be acknowledged any other principle than that which is to be found on all the surface of the earth, a principle of generation in one sense, and of destruction in another.

We may also find in this particular, a certain degree of confirmation to another part of the same theory; a part which does not come so immediately within our view, and concerning which so many contradictory hypotheses have been formed. Naturalists have supposed a certain original construction of mountains, which constitution of things, however, they never have explained; they have also distinguished those which have evidently been formed in another manner, that is to say, those the materials of which had been collected in the ocean. Now, here are two things perfectly different; on the one hand original mountains formed by nature, but we know not how, endued with solidity, but not differing in this respect from those of a posterior formation; on the other hand, secondary mountains, formed by the collection of materials in the sea, therefore, not having solidity as a quality inherent in their constitution, but only occasional or accidental in their nature. If, therefore, it be the natural constitution of things upon the surface of this earth to indurate and become solid, however originally formed loose and incoherent, we should thus find an explanation of the consolidation of those masses which had been lately formed of the loose materials of the ocean; if, on the contrary, we find those pretended primitive mountains, those bodies which are endued with hardness and solidity, wasting by the hand of time, and thus wearing in the operations natural to the surface of the earth, Where shall we find the consolidating operations, those by which beds of shells have been transformed into perfect marble, and siliceous bodies into solid flint? or how reconcile those opposite intentions in the same cause?

Nothing can be more absurd than to suppose a collection of shells and corals, amassed about the primitive mountains of the earth, to become mountains equally solid with the others, upon the removal of the sea; it would be inconsistent with every principle of sound reasoning to suppose those masses of loose materials to oppose equal resistance to the wasting and destroying operations of the surface of the earth, as do those pretended primitive masses, which might be supposed endued with natural hardness and solidity; yet, consult the matter of fact, and it does not appear that there is any difference to be perceived. There are lofty mountains to be found both of the one kind and the other; both those different masses yield to the wasting operations of the surface; and they are both carried away with the descending waters of the earth.

It is not here meant to affirm, that a mass of marble, which is a calcareous substance, opposes equal resistance, whether to the operations of dissolution or attrition, as a mass composed of granite or of quartz; it is only here maintained that there are in the Alps lofty mountains of marble, as there are in other places lower masses of granite and its accompanying schistus. But that which is particularly to be attended to here is this: In all countries of the earth, whether of primitive masses or those of secondary formation, whether uniform and homogeneous, or compound and mixed of those two different kinds of bodies, the system is always the same, of hills and valleys, lakes and rivers, ravines and streams: no man can say, by looking into the most perfect map, what is primary or what secondary in the constitution of the globe. It is the same system of larger rivers branching into lesser and lesser in a continued series, of smaller rivers in like manner branching into rivulets, and of rivulets terminating at last into springs or temporary streams. The principle is universal; and, having learned the natural history of one river, we know the constitution of every other upon the face of the earth.

Thus all the surface of this earth is formed according to a regular system of heights and hollows, hills and valleys, rivulets and rivers, and these rivers return the waters of the atmosphere into the general mass, in like manner as the blood, returning to the heart, is conducted in the veins. But as the solid land, formed at the bottom of the sea or in the bowels of the earth, could not be there constructed according to that system of things which we find so widely pursued upon the surface of the globe, it must be by wasting the solid parts of the land that this system of the surface has been formed, in like manner as it is by the operations of the sea that the shape of the land is determined, upon the shore.

Thus it has been shown, that the general tendency of the operations natural to the surface of the globe is to wear the surface of the earth, and waste the land; consequently that, however long the continents of this earth may be supposed to last, they are on the whole in a constant state of diminution and decay; and, in the progress of time, will naturally disappear. Hence confirmation is added to that mineral system of the earth, by which the present land is supposed to have acquired solidity and hardness; and according to which future land is supposed to be preparing from the materials of the sea and former continents; which land will be brought to light in time, to supply the place of that which necessarily wastes, in serving plants and animals. But what is here more particularly to the purpose is this; that we find an explanation of that various shape and conformation which is to be observed upon the surface of this earth, as being the effect of causes which are constant and unremitting in their operation, which are widely adapted to the end or absolutely necessary in the system of this world, and which, in the indefinite course of time, become unlimited in their effect, or powerful in any conceivable degree.

It is not sufficient for establishing the present theory, to refute that most unscientific hypothesis, adopted by some eminent philosophers, of mountains and valleys being the effect of currents in the ocean; it is necessary to see what is their proper cause, and to show that by no other cause known could the general effect, which is of such importance in the system of this world, be actually produced. It is for this reason that we have endeavoured to show that there is a general, an universal system of river and valley, which renders the surface of this earth a sort of organized body destined to a purpose which it perfectly fulfils.

But to see the full force of this argument, taken from that order of things which is perceived in that system of valley and river all over the earth, let us examine, first, what would be the effect, in the constitution of this world, of bodies of land formed upon no such system; and, secondly, what would be the effect of the natural constitution of this world and meteorological operations of the atmosphere, if continued for a sufficient length of time, upon a mass of land without any systematic form.

For this purpose we shall take for example a portion of this earth, which is the best known to us, that is the south-western part of Europe, in order to compare its present state, which so perfectly fulfils the purpose of this world, with that in which no order of valley and of rivers should be fund.

Let us begin at the summit, which is the Mont-Blanc. At present the water, falling from the heavens upon this continent, is gathered into a system of rivers which run through valleys, and is delivered at last into the Adriatic, the Mediterranean, the Atlantic, and the German Seas; all the rest of this continent, except some lakes and marshes, is dry land, properly calculated, for the sustenance of a variety of plants and animals, and so fulfils the purpose of a habitable earth. Now, destroy that system of river and valley, and the whole would become a mixture of lakes and marshes, except the summits of a few barren rocks and mountains. No regular channels for conveying the super-abundant water being made, every thing must be deluged, and nothing but a system of aquatic plants and animals appear. A continent of this sort is not found upon the globe; and such a constitution of things, in general, would not answer the purpose of the habitable world which we possess. It is therefore necessary to modify the surface of such a continent of land, as had been formed in the sea, and produced, by whatever means, into the atmosphere for the purpose of maintaining that variety of plants and animals which we behold; and now we are to examine how far the proper means for that modification is to be found necessarily in the constitution of this world.

If we consider our continent as composed of such materials as may decay by the influence of the atmosphere, and be moved by water descending from the higher to the lower ground, as is actually the case with the land of our globe, then the water would gradually form channels in which it would run from place to place; and those channels, continually uniting as they proceed to the sea or shore, would form a system of rivers and their branchings. But this system of moving water must gradually produce valleys, by carrying away stones and earthy matter in their floods; and those valleys would be changing according to the softness, and hardness, destructability or indestructability of the solid parts below. Still however the system of valley and river would be preserved; and to this would be added the system of mountains, and valleys, of hills and plains, to the formation of which the unequal wearing down of the solids must in a great measure contribute.

Here therefore it is evident, first, that the great system upon the surface of this earth, is that of valleys and rivers; secondly, that no such system could arise from the operations of the sea when covering the nascent land; thirdly, that this system is accomplished by the same means which, are employed for procuring soil from the decaying rocks and strata; and, lastly, that however this system shall be interrupted and occasionally destroyed, it would necessarily be again formed in time, while the earth continued above the level of the sea. Whatever changes take place from the operation of internal causes, the habitable earth, in general, is always preserved with the vigour of youth, and the perfection of the most mature age. We cannot see man cultivate the field, without perceiving that system of dry land provided by nature in forming valleys and rivers; we cannot study the rocks and solid strata of the earth, those bulwarks of the field and shore, without acknowledging the provident design of nature in giving as much permanency to our continent, as is consistent with sufficient fertility; and we cannot contemplate the necessary waste of a present continent, without perceiving the means for laying the foundation of another. But the evidence of those truths is not open to a vulgar view; media are required, or much reasoning; and between the first link and the last, in this chain, what a distance, from the wasting of hard bodies upon the surface of the earth, to the formation of a solid rock at the bottom of the sea.

The system of this earth appears to comprehend many different operations; and it exhibits various powers co-operating for the production of those effects which we perceive. Of this we are informed by studying natural appearances; and in this manner we are led to understand the nature of things, in knowing causes.

That our land, which is now above the level of the sea, had been formerly under water, is a fact for which there is every where the testimony of a multitude of observations. This indeed is a fact which is admitted upon all hands; it is a fact upon which the speculations of philosophers have been already much employed; but it is a fact still more important, in my opinion, than it has been ever yet considered. It is not, however, as a solitary fact that any rational system may be founded upon this truth, That the earth had been formerly at the bottom of the sea; we must also see the nature and constitution of this earth as necessarily subsisting in continual change; and we must see the means employed by nature for constructing a continent of solid land in the fluid bosom of the deep. It is then that we may judge of that design, by finding ends and means contrived in wisdom, that is to say, properly adapted to each other.

We have now given a theory founded upon the actual state of this earth, and the appearances of things, so far as they are changing; and we have, in support of that theory, adduced the observations of scientific men, who have carefully examined nature and described things in a manner that is clear and intelligible. We are now to take a review of the principle points on which this theory hangs; and to endeavour to point out the importance of the subject, and the proper manner of judging with regard to a theory of the earth, how far it is conform to the general system of nature, which has for object a world.

If it should be admitted, that this earth had been formed by the collection of materials deposited within the sea, there will then appear to be certain things which ought to be explained by a theory, before that theory be received as belonging to this earth. These are as follows:

First, We ought to show how it came about that this whole earth, or by far the greatest part in all the quarters of the globe, had been formed of transported materials collected together in the sea. It must be here remembered, that the highest of our mountainous countries are equally formed of those travelled materials as are the lowest of our plains; we are not therefore to have recourse to any thing that we see at present for the origin of those materials which actually compose the earth; and we must show from whence had come those travelled materials, manufactured by water, which were employed in composing the highest places of our land.

Secondly, We must explain how those loose and incoherent materials had been consolidated, as we find they are at present. We are not here to allow ourselves the liberty, which naturalists have assumed without the least foundation, of explaining every thing of this sort by infiltration, a term in this case expressing nothing but our ignorance.

Thirdly, The strata are not always equally consolidated. We often find contiguous strata in very different states with respect to solidity; and sometimes the most solid masses are found involved in the most porous substance. Some explanation surely would be expected for this appearance, which is of a nature so conclusive as ought to attract the attention of a theorist.

Fourthly, It is not sufficient to show how the earth in general had been consolidated; we must also explain, how it comes to pass that the consolidated bodies are always broken and intersected by veins and fissures. In this case, the reason commonly given, that the earth exposed to the atmosphere had shrunk like moist clay, or contracted by the operation of drying, can only show that such naturalists have thought but little upon the subject. The effect in no shape or degree corresponds to that cause; and veins and fissures, in the solid bodies, are no less frequent under the level of the sea, than on the summits of our mountains.

Fifthly, Having found a cause for the fracture and separation of the solid masses, we must also tell from whence the matter with which those chasms are filled, matter which is foreign both to the earth and sea, had been introduced into the veins that intersect the strata. If we fail in this particular, What credit could be given to such hypotheses as are contrived for the explanation of more ambiguous appearances, even when those suppositions should appear most probable?

Sixthly, Supposing that hitherto every thing had been explained in the most satisfactory manner, the most important appearances of our earth still remain to be considered. We find those strata that were originally formed continuous in their substance, and horizontal in their position, now broken, bended, and inclined, in every manner and degree; we must give some reason in our theory for such a general changed state and disposition of things; and we must tell by what power this event, whether accidental or intended, had been brought about.

Lastly, Whatever powers had been employed in preparing land, while situated under water, or at the bottom of the sea, the most powerful operation yet remains to be explained; this is the means by which the lowest surface of the solid globe was made to be the highest upon the earth. Unless we can show a power of sufficient force, and placed in a proper situation for that purpose, our theory would go for nothing, among people who investigate the nature of things, and who, founding on experience, reason by induction from effect to cause.

Nothing can be admitted as a theory of the earth which does not, in a satisfactory manner, give the efficient causes for all these effects already enumerated. For, as things are universally to be acknowledged in the earth, it is essential in a theory to explain those natural appearances.

But this is not all. We live in a world where order every where prevails; and where final causes are as well known, at least, as those which are efficient. The muscles, for example, by which I move my fingers when I write, are no more the efficient cause of that motion, than this motion is the final cause for which the muscles had been made. Thus, the circulation of the blood is the efficient cause of life; but, life is the final cause, not only for the circulation of the blood, but for the revolution of the globe: Without a central luminary, and a revolution of the planetary body, there could not have been a living creature upon the face of this earth; and, while we see a living system on this earth, we must acknowledge, that in the solar system we see a final cause.

Now, in a theory which considers this earth as placed in a system of things where ends are at least attained, if not contrived in wisdom, final causes must appear to be an object of consideration, as well as those which are efficient. A living world is evidently an object in the design of things, by whatever Being those things had been designed, and however either wisdom or folly may appear in that design. Therefore the explanation, which is given of the different phenomena of the earth, must be consistent with the actual constitution of this earth as a living world, that is, a world maintaining a system of living animals and plants.

Not only are no powers to be employed that are not natural to the globe, no action to be admitted of except those of which we know the principle, and no extraordinary events to be alledged in order to explain a common appearance, the powers of nature are not to be employed in order to destroy the very object of those powers; we are not to make nature act in violation to that order which we actually observe, and in subversion of that end which is to be perceived in the system of created things. In whatever manner, therefore, we are to employ the great agents, fire and water, for producing those things which appear, it ought to be in such a way as is consistent with the propagation of plants and life of animals upon the surface of the earth. Chaos and confusion are not to be introduced into the order of nature, because certain things appear to our partial views as being in some disorder. Nor are we to proceed in feigning causes, when those seem insufficient which occur in our experience.

Animal life being thus considered as an object in the view of nature, we are to consider this earth as being the means appointed for that end; and then the question is suggested, How far wisdom may appear in the constitution of this earth, as being means properly adapted to the system of animal life, which is evidently the end. This is taking for granted, that there is a known system of the earth which is to be tried--how far properly adapted to the end intended in nature. But, it is this very system of the earth which is here the subject of investigation; and, it is in order to discover the true system that we are to examine, by means of final causes, every theory which pretends to show the nature of that system, or to assign efficient causes to physical events.

Here then we have a rule to try the propriety of every operation which should be acknowledged as in the system of nature, or as belonging to the theory of this earth. It is not necessary that we should see the propriety of every natural operation; our natural ignorance precludes us from any title to form a judgment in things of which we are not properly informed; but, no suppositions of events, or explanations of natural appearances, are to be admitted into our Theory, if the propriety of those alledged operations is not made to appear. We are now to make an application.

This earth, which is now dry land, was under water, and was formed in the sea. Here is a matter of fact, and not of theory, so far as it can be made as evident as any thing of which we have not seen the immediate act or execution. But the propriety of this matter of fact is only to be perceived in making the following acknowledgment, That the origin of this earth is necessarily placed in the bottom of the sea. In supposing any other origin to this habitable earth, we would see the impropriety of having it covered with water, or drowned in the sea. But, being formed originally at the bottom of the sea, if we can explain the phenomena of this earth by natural causes, we will acknowledge the wisdom of those means, by which the earth, thus formed at the bottom of the sea, had been perfected in its nature, and made to fulfil the purpose of its intention, by being placed in the atmosphere.

If the habitable earth does not take its origin in the waters of the sea, the washing away of the matter of this earth into the sea would put a period to the existence of that system which forms the admirable constitution of this living world. But, if the origin of this earth is founded in the sea, the matter which is washed from our land is only proceeding in the order of the system; and thus no change would be made in the general system of this world, although this particular earth, which we possess at present, should in the course of nature disappear.

It has already been our business to show that the land is actually wasted universally, and carried away into the sea. Now, What is the final cause of this event?--Is it in order to destroy the system of this living world, that the operations of nature are thus disposed upon the surface of this earth? Or, Is it to perpetuate the progress of that system, which, in other respects, appears to be contrived with so much wisdom? Here are questions which a Theory of the Earth must solve; and here indeed, must be found the most material part by far of any Theory of the Earth. For, as we are more immediately concerned with the operations of the surface, it is the revolutions of that surface which forms, for us, the most interesting subject of inquiry.

Thus we are led to inquire into the final cause of things, while we investigate an operation of such magnitude and importance, as is that of forming land of sea, and sea of land, of apparently reversing nature, and of destroying that which is so admirably adapted to its purpose. Was it the work of accident, or effect of an occasional transaction, that by which the sea had covered our land? Or, Was it the intention of that Mind which formed the matter of this globe, which endued that matter with its active and its passive powers, and which placed it with so much wisdom among a numberless collection of bodies, all moving in a system? If we admit the first, the consequence of such a supposition would be to attribute to chance the constitution of this world, in which the systems of life and sense, of reason and intellect, are necessarily maintained. If again we shall admit, that there is intention in the cause by which the present earth had been removed from the bottom of the sea, we may then inquire into the nature of that system in which a habitable earth, possessed of beauty, arranged in order, and preserved with economy, had been formed by the mixture and combination of the different elements, and made to rise out of the wreck of a former world.

In examining the structure of our earth, we find it no less evidently formed of loose and incoherent materials, than that those materials had been collected from different parts, and gathered together at the bottom of the sea. Consequently, if this continent of land, first collected in the sea, and then raised above its surface, is to remain a habitable earth, and to resist the moving waters of the globe, certain degrees of solidity or consolidation must be given to that collection of loose materials; and certain degrees of hardness must be given to bodies which were soft or incoherent, and consequently so extremely perishable in the situation where they now are placed.

But, at the same time that this earth must have solidity and hardness to resist the sudden changes which its moving fluids would occasion, it must be made subject to decay and, waste upon the surface exposed to the atmosphere; for, such an earth as were made incapable of change, or not subject to decay, could not afford that fertile soil which is required in the system of this world, a soil on which depends the growth of plants and life of animals,--the end of its intention.

Now, we find this earth endued precisely with that degree of hardness and consolidation, as qualifies it at the same time to be a fruitful earth, and to maintain its station with all the permanency compatible with the nature of things, which are not formed to remain unchangeable.

Thus we have a view of the most perfect wisdom, in the contrivance of that constitution by which the earth is made to answer, in the best manner possible, the purpose of its intention, that is, to maintain and perpetuate a system of vegetation, or the various race of useful plants, and a system of living animals, which are in their turn subservient to a system still infinitely more important, I mean, a system of intellect. Without fertility in the earth, many races of plants and animals would soon perish, or be extinct; and, without permanency in our land, it were impossible for the various tribes of plants and animals to be dispersed over all the surface of a changing earth. The fact is, that fertility, adequate to the various ends in view, is found in all the quarters of the world, or in every country of the earth; and, the permanency of our land is such, as to make it appear unalterable to mankind in general, and even to impose upon men of science, who have endeavoured to persuade us that this earth is not to change. Nothing but supreme power and wisdom could have reconciled those two opposite ends of intention, so as both to be equally pursued in the system of nature, and both so equally attained as to be imperceptible to common observation, and at the same time a proper object for the human understanding.

We thus are led to inquire into the efficient causes of this constitution of things, by which solidity and stability had been bestowed upon a mass of loose materials, and by which this solid earth, formed first at the bottom of the sea, had been placed in the atmosphere, where plants and animals find the necessary conditions of their life.

Now, we have shown, that subterraneous fire and heat had been employed in the consolidation of our earth, and in the erection of that consolidated body into the place of land. The prejudices of mankind, who cannot see the steps by which we come at this conclusion, are against the doctrine; but, prejudice must give way to evidence. No other Theory will in any degree explain appearances, while almost every appearance is easily explained by this Theory.

We do not dispute the chymical action and efficacy of water, or any other substance which is found among the materials collected at the bottom of the sea; we only mean to affirm, that every action of this kind is incapable of producing perfect solidity in the body of earth in that situation of things, whatever time should be allowed for that operation, and that whatever may have been the operations of water, aided by fire, and evaporated by heat, the various appearances of mineralization, (every where presented to us in the solid earth, and the most perfect objects of examination), are plainly inexplicable upon the principle of aqueous solution. On the other hand, the operation of heat, melting incoherent bodies, and introducing softness into rigid substances which are to be united, is not only a cause which is proper to explain the effects in question, but also appears, from a multitude of different circumstances, to have been actually exerted among the consolidated bodies of our earth, and in the mineral veins with which the solid bodies of the earth abound.

The doctrine, therefore, of our Theory is briefly this, That, whatever may have been the operation of dissolving water, and the chymical action of it upon the materials accumulated at the bottom of the sea, the general solidity of that mass of earth, and the placing of it in the atmosphere above the surface of the sea, has been the immediate operation of fire or heat melting and expanding bodies. Here is a proposition which may be tried, in applying it to all the phenomena of the mineral region; so far as I have seen, it is perfectly verified in that application.

We have another proposition in our Theory; one which is still more interesting to consider. It is this, That as, in the mineral regions, the loose or incoherent materials of our land had been consolidated by the action of heat; so, upon the surface of this earth exposed to the fluid elements of air and water, there is a necessary principle of dissolution and decay, for that consolidated earth which from the mineral region is exposed to the day. The solid body being thus gradually impaired, there are moving powers continually employed, by which the summits of our land are constantly degraded, and the materials of this decaying surface travelled towards the coast. There are other powers which act upon the shore, by which the coast is necessarily impaired, and our land subjected to the perpetual incroachment of the ocean.

Here is a part of the Theory with which every appearance of the surface may be compared. I am confident that it will stand the test of the most rigid examination; and that nothing but the most inconsiderate judgment may mistake a few appearances, which, when properly understood, instead of forming any subject of objection to the Theory, will be found to afford it every reasonable support or confirmation.

We have now seen, that in every quarter of the globe, and in every climate of the earth, there is formed, by means of the decay of solid rocks, and by the transportation of those moveable materials, that beautiful system of mountains and valleys, of hills and plains, covered with growing plants, and inhabited by animals. We have seen, that, with this system of animal and vegetable economy, which depends on soil and climate, there is also a system of moving water, poured upon the surface of the earth[30], in the most beneficial manner possible for the use of vegetation, and the preservation of our soil; and that this water is gathered together again by running to the lowest place, in order to avoid accumulation of water upon the surface, which would be noxious.

[Footnote 30: See Dissertations upon Subjects of Natural Philosophy, Part I.]

It is in this manner that we first have streams or torrents, which only run in times of rain. But the rain-water absorbed into the earth is made to issue out in springs, which run perpetually, and which, gathering together as they run, form rivulets, watering valleys, and delighting the various inhabitants of this earth. The rivulets again are united in their turn, and form those rivers which overflow our plains, and which alternately bring permanent fertility and casual devastation to our land. Those rivers, augmenting in their volume as they unite, pour at last their mighty waters into the ocean; and thus is completed that circulation of wholesome fluids, which the earth requires in order to be a habitable world.

Our Theory farther shows, that in the ocean there is a system of animals which have contributed so materially to the formation of our land. These animals are necessarily maintained by the vegetable provision, which is returned in the rivers to the sea, and which the land alone or principally produces. Thus we may perceive the mutual dependence upon each other of those two habitable worlds,--the fluid ocean and the fertile earth.

The land is formed in the sea, and in great part by inhabitants of that fluid world. But those animals, which form with their exuviae such a portion of the land, are maintained, like those upon the surface of the earth, by the produce of that land to which they formerly had contributed. Thus the vegetable matter, which is produced upon the surface of the earth in such abundance for the use of animals, and which, in such various shapes, is carried by the rivers into the sea, there sustains that living system which is daily employed to make materials for a future land.

Here is a compound system of things, forming together one whole living world; a world maintaining an almost endless diversity of plants and animals, by the disposition of its various parrs, and by the circulation of its different kinds of matter. Now, we are to examine into the necessary consequence of this disposition of things, where the matter of this active world is perpetually moved, in that salutary circulation by which provision is so wisely made for the growth and prosperity of plants, and for the life and comfort of its various animals.

If, in examining this subject, we shall find that there is nothing in the system but what is necessary, that is, nothing in the means employed but what the importance of the end requires; if we shall find that the end is steadily pursued, and that there is no deficiency in the means which are employed; and if it shall be acknowledged that the end which is attained is not idle or insignificant, we then may draw this conclusion, That such a system is in perfect wisdom; and therefore that this system, so far as it is found corresponding properly with natural appearances, is the system of nature, and not the creature of imagination.

Let us then take a cursory view of this system of things, upon which we have proceeded in our theory, and upon which the constitution of this world seems to depend.

Our solid earth is every where wasted, where exposed to the day. The summits of the mountains are necessarily degraded. The solid and weighty materials of those mountains are every where urged through the valleys, by the force of running water. The soil, which is produced in the destruction of the solid earth, is gradually travelled by the moving water, but is constantly supplying vegetation with its necessary aid. This travelled soil is at last deposited upon the coast, where it forms most fertile countries. But the billows of the ocean agitate the loose materials upon the shore, and wear away the coast, with the endless repetitions of this act of power, or this imparted force. Thus the continent of our earth, sapped in its foundation, is carried away into the deep, and sunk again at the bottom of the sea, from whence it had originated.

We are thus led to see a circulation in the matter of this globe, and a system of beautiful economy in the works of nature. This earth, like the body of an animal, is wasted at the same time that it is repaired. It has a state of growth and augmentation; it has another state, which is that of diminution and decay. This world is thus destroyed in one part, but it is renewed in another; and the operations by which this world is thus constantly renewed, are as evident to the scientific eye, as are those in which it is necessarily destroyed. The marks of the internal fire, by which the rocks, beneath the sea are hardened, and by which the land is produced above the surface of the sea, have nothing in them which is doubtful or ambiguous. The destroying operations again, though placed within the reach of our examination, and evident almost to every observer, are no more acknowledged by mankind, than is that system of renovation which philosophy alone discovers.

It is only in science that any question concerning the origin and end of things is formed; and it is in science only that the resolution of those questions is to be attained. The natural operations of this globe, by which the size and shape of our land are changed, are so slow as to be altogether imperceptible to men who are employed in pursuing the various occupations of life and literature. We must not ask the industrious inhabitant, for the end or origin of this earth: he sees the present, and he looks no farther into the works of time than his experience can supply his reason. We must not ask the statesman, who looks into the history of time past, for the rise and fall of empires; he proceeds upon the idea of a stationary earth, and most justly has respect to nothing but the influence of moral causes.

It is in the philosophy of nature that the natural history of this earth is to be studied; and we must not allow ourselves ever to reason without proper data, or to fabricate a system of apparent wisdom in the folly of a hypothetical delusion.

When, to a scientific view of the subject, we join the proof which has been given, that in all the quarters of the globe, in every place upon the surface of the earth, there are the most undoubted marks of the continued progress of those operations which wear away and waste the land, both in its height and width, its elevation and extention, and that for a space of duration in which our measures of time are lost, we must sit down contented with this limitation of our retrospect, as well as prospect, and acknowledge, that it is in vain to seek for any computation of the time, during which the materials of this earth had been prepared in a preceding world, and collected at the bottom of a former sea.

The system of this earth will thus appear to comprehend many different operations, or it exhibits various powers co-operating for the production of those appearances which we properly understand in knowing causes. Thus, in order to understand the natural conformation of this country, or the particular shape of any other place upon the globe, it is not enough to see the effects of those powers which gradually waste and wear away the surface, we must also see how those powers affecting the surface operate, or by what principle they act.

Besides, seeing those powers which are employed in thus changing the surface of the earth, we must also observe how their force is naturally augmented with the declivity of the ground on which they operate. Neither is it sufficient to understand by what powers the surface is impaired, for, it may be asked, why, in equal circumstances, one part is more impaired than another; this then leads to the examination of the mineral system, in which are determined the hardness and solidity, consequently, the permanency of those bodies of which our land is composed; and here are sources of indefinite variety.

In the system of the globe every thing must be consistent. The changing and destroying operations of the surface exposed to the sun and influences of the atmosphere, must correspond to those by which land is composed at the bottom of the sea; and the consolidating operations of the mineral region must correspond to those appearances which in the rocks, the veins, and solid stones, give such evident, such universal testimony of the power of fire, in bringing bodies into fusion, or introducing fluidity, the necessary prelude to solidity and concretion.

Those various powers of nature have thus been employed in the theory, to explain things which commonly appear; or rather, it is from things which universally appear that causes have been concluded, upon scientific principles, for those effects. A system is thus formed, in generalising all those different effects, or in ascribing all those particular operations to a general end. This end, the subject of our understanding, is then to be considered as an object of design; and, in this design, we may perceive, either wisdom, so far as the ends and means are properly adapted, or benevolence, so far as that system is contrived for the benefit of beings who are capable of suffering pain and pleasure, and of judging good and evil.

But, in this physical dissertation, we are limited to consider the manner in which things present have been made to come to pass, and not to inquire concerning the moral end for which those things may have been calculated. Therefore, in pursuing this object, I am next to examine facts, with regard to the mineralogical part of the theory, from which, perhaps, light may be thrown upon the subject; and to endeavour to answer objections, or solve difficulties, which may naturally occur from the consideration of particular appearances.

END OF VOLUME SECOND.

End of the Project Gutenberg EBook of Theory of the Earth, Volume 2 (of 4) by James Hutton

*** END OF THIS PROJECT GUTENBERG EBOOK THEORY OF THE EARTH ***

***** This file should be named 14179-8.txt or 14179-8.zip ***** This and all associated files of various formats will be found in: https://www.gutenberg.org/1/4/1/7/14179/

Updated editions will replace the previous one--the old editions will be renamed.

Creating the works from public domain print editions means that no one owns a United States copyright in these works, so the Foundation (and you!) can copy and distribute it in the United States without permission and without paying copyright royalties. Special rules, set forth in the General Terms of Use part of this license, apply to copying and distributing Project Gutenberg-tm electronic works to protect the PROJECT GUTENBERG-tm concept and trademark. Project Gutenberg is a registered trademark, and may not be used if you charge for the eBooks, unless you receive specific permission. If you do not charge anything for copies of this eBook, complying with the rules is very easy. You may use this eBook for nearly any purpose such as creation of derivative works, reports, performances and research. They may be modified and printed and given away--you may do practically ANYTHING with public domain eBooks. Redistribution is subject to the trademark license, especially commercial redistribution.

*** START: FULL LICENSE ***

THE FULL PROJECT GUTENBERG LICENSE PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK

To protect the Project Gutenberg-tm mission of promoting the free distribution of electronic works, by using or distributing this work (or any other work associated in any way with the phrase "Project Gutenberg"), you agree to comply with all the terms of the Full Project Gutenberg-tm License (available with this file or online at https://gutenberg.org/license).

Section 1. General Terms of Use and Redistributing Project Gutenberg-tm electronic works

1.A. By reading or using any part of this Project Gutenberg-tm electronic work, you indicate that you have read, understand, agree to and accept all the terms of this license and intellectual property (trademark/copyright) agreement. If you do not agree to abide by all the terms of this agreement, you must cease using and return or destroy all copies of Project Gutenberg-tm electronic works in your possession. If you paid a fee for obtaining a copy of or access to a Project Gutenberg-tm electronic work and you do not agree to be bound by the terms of this agreement, you may obtain a refund from the person or entity to whom you paid the fee as set forth in paragraph 1.E.8.

1.B. "Project Gutenberg" is a registered trademark. It may only be used on or associated in any way with an electronic work by people who agree to be bound by the terms of this agreement. There are a few things that you can do with most Project Gutenberg-tm electronic works even without complying with the full terms of this agreement. See paragraph 1.C below. There are a lot of things you can do with Project Gutenberg-tm electronic works if you follow the terms of this agreement and help preserve free future access to Project Gutenberg-tm electronic works. See paragraph 1.E below.

1.C. The Project Gutenberg Literary Archive Foundation ("the Foundation" or PGLAF), owns a compilation copyright in the collection of Project Gutenberg-tm electronic works. Nearly all the individual works in the collection are in the public domain in the United States. If an individual work is in the public domain in the United States and you are located in the United States, we do not claim a right to prevent you from copying, distributing, performing, displaying or creating derivative works based on the work as long as all references to Project Gutenberg are removed. Of course, we hope that you will support the Project Gutenberg-tm mission of promoting free access to electronic works by freely sharing Project Gutenberg-tm works in compliance with the terms of this agreement for keeping the Project Gutenberg-tm name associated with the work. You can easily comply with the terms of this agreement by keeping this work in the same format with its attached full Project Gutenberg-tm License when you share it without charge with others.

1.D. The copyright laws of the place where you are located also govern what you can do with this work. Copyright laws in most countries are in a constant state of change. If you are outside the United States, check the laws of your country in addition to the terms of this agreement before downloading, copying, displaying, performing, distributing or creating derivative works based on this work or any other Project Gutenberg-tm work. The Foundation makes no representations concerning the copyright status of any work in any country outside the United States.

1.E. Unless you have removed all references to Project Gutenberg:

1.E.1. The following sentence, with active links to, or other immediate access to, the full Project Gutenberg-tm License must appear prominently whenever any copy of a Project Gutenberg-tm work (any work on which the phrase "Project Gutenberg" appears, or with which the phrase "Project Gutenberg" is associated) is accessed, displayed, performed, viewed, copied or distributed:

1.E.2. If an individual Project Gutenberg-tm electronic work is derived from the public domain (does not contain a notice indicating that it is posted with permission of the copyright holder), the work can be copied and distributed to anyone in the United States without paying any fees or charges. If you are redistributing or providing access to a work with the phrase "Project Gutenberg" associated with or appearing on the work, you must comply either with the requirements of paragraphs 1.E.1 through 1.E.7 or obtain permission for the use of the work and the Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or 1.E.9.

1.E.3. If an individual Project Gutenberg-tm electronic work is posted with the permission of the copyright holder, your use and distribution must comply with both paragraphs 1.E.1 through 1.E.7 and any additional terms imposed by the copyright holder. Additional terms will be linked to the Project Gutenberg-tm License for all works posted with the permission of the copyright holder found at the beginning of this work.

1.E.4. Do not unlink or detach or remove the full Project Gutenberg-tm License terms from this work, or any files containing a part of this work or any other work associated with Project Gutenberg-tm.

1.E.5. Do not copy, display, perform, distribute or redistribute this electronic work, or any part of this electronic work, without prominently displaying the sentence set forth in paragraph 1.E.1 with active links or immediate access to the full terms of the Project Gutenberg-tm License.

1.E.6. You may convert to and distribute this work in any binary, compressed, marked up, nonproprietary or proprietary form, including any word processing or hypertext form. However, if you provide access to or distribute copies of a Project Gutenberg-tm work in a format other than "Plain Vanilla ASCII" or other format used in the official version posted on the official Project Gutenberg-tm web site (www.gutenberg.org), you must, at no additional cost, fee or expense to the user, provide a copy, a means of exporting a copy, or a means of obtaining a copy upon request, of the work in its original "Plain Vanilla ASCII" or other form. Any alternate format must include the full Project Gutenberg-tm License as specified in paragraph 1.E.1.

1.E.7. Do not charge a fee for access to, viewing, displaying, performing, copying or distributing any Project Gutenberg-tm works unless you comply with paragraph 1.E.8 or 1.E.9.

1.E.8. You may charge a reasonable fee for copies of or providing access to or distributing Project Gutenberg-tm electronic works provided that

- You pay a royalty fee of 20% of the gross profits you derive from the use of Project Gutenberg-tm works calculated using the method you already use to calculate your applicable taxes. The fee is owed to the owner of the Project Gutenberg-tm trademark, but he has agreed to donate royalties under this paragraph to the Project Gutenberg Literary Archive Foundation. Royalty payments must be paid within 60 days following each date on which you prepare (or are legally required to prepare) your periodic tax returns. Royalty payments should be clearly marked as such and sent to the Project Gutenberg Literary Archive Foundation at the address specified in Section 4, "Information about donations to the Project Gutenberg Literary Archive Foundation."

- You provide a full refund of any money paid by a user who notifies you in writing (or by e-mail) within 30 days of receipt that s/he does not agree to the terms of the full Project Gutenberg-tm License. You must require such a user to return or destroy all copies of the works possessed in a physical medium and discontinue all use of and all access to other copies of Project Gutenberg-tm works.

- You provide, in accordance with paragraph 1.F.3, a full refund of any money paid for a work or a replacement copy, if a defect in the electronic work is discovered and reported to you within 90 days of receipt of the work.

- You comply with all other terms of this agreement for free distribution of Project Gutenberg-tm works.

1.E.9. If you wish to charge a fee or distribute a Project Gutenberg-tm electronic work or group of works on different terms than are set forth in this agreement, you must obtain permission in writing from both the Project Gutenberg Literary Archive Foundation and Michael Hart, the owner of the Project Gutenberg-tm trademark. Contact the Foundation as set forth in Section 3 below.

1.F.

1.F.1. Project Gutenberg volunteers and employees expend considerable effort to identify, do copyright research on, transcribe and proofread public domain works in creating the Project Gutenberg-tm collection. Despite these efforts, Project Gutenberg-tm electronic works, and the medium on which they may be stored, may contain "Defects," such as, but not limited to, incomplete, inaccurate or corrupt data, transcription errors, a copyright or other intellectual property infringement, a defective or damaged disk or other medium, a computer virus, or computer codes that damage or cannot be read by your equipment.

1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right of Replacement or Refund" described in paragraph 1.F.3, the Project Gutenberg Literary Archive Foundation, the owner of the Project Gutenberg-tm trademark, and any other party distributing a Project Gutenberg-tm electronic work under this agreement, disclaim all liability to you for damages, costs and expenses, including legal fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE PROVIDED IN PARAGRAPH F3. YOU AGREE THAT THE FOUNDATION, THE TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH DAMAGE.

1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a defect in this electronic work within 90 days of receiving it, you can receive a refund of the money (if any) you paid for it by sending a written explanation to the person you received the work from. If you received the work on a physical medium, you must return the medium with your written explanation. The person or entity that provided you with the defective work may elect to provide a replacement copy in lieu of a refund. If you received the work electronically, the person or entity providing it to you may choose to give you a second opportunity to receive the work electronically in lieu of a refund. If the second copy is also defective, you may demand a refund in writing without further opportunities to fix the problem.

1.F.4. Except for the limited right of replacement or refund set forth in paragraph 1.F.3, this work is provided to you 'AS-IS' WITH NO OTHER WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTIBILITY OR FITNESS FOR ANY PURPOSE.

1.F.5. Some states do not allow disclaimers of certain implied warranties or the exclusion or limitation of certain types of damages. If any disclaimer or limitation set forth in this agreement violates the law of the state applicable to this agreement, the agreement shall be interpreted to make the maximum disclaimer or limitation permitted by the applicable state law. The invalidity or unenforceability of any provision of this agreement shall not void the remaining provisions.

1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the trademark owner, any agent or employee of the Foundation, anyone providing copies of Project Gutenberg-tm electronic works in accordance with this agreement, and any volunteers associated with the production, promotion and distribution of Project Gutenberg-tm electronic works, harmless from all liability, costs and expenses, including legal fees, that arise directly or indirectly from any of the following which you do or cause to occur: (a) distribution of this or any Project Gutenberg-tm work, (b) alteration, modification, or additions or deletions to any Project Gutenberg-tm work, and (c) any Defect you cause.

Section 2. Information about the Mission of Project Gutenberg-tm

Project Gutenberg-tm is synonymous with the free distribution of electronic works in formats readable by the widest variety of computers including obsolete, old, middle-aged and new computers. It exists because of the efforts of hundreds of volunteers and donations from people in all walks of life.

Volunteers and financial support to provide volunteers with the assistance they need, is critical to reaching Project Gutenberg-tm's goals and ensuring that the Project Gutenberg-tm collection will remain freely available for generations to come. In 2001, the Project Gutenberg Literary Archive Foundation was created to provide a secure and permanent future for Project Gutenberg-tm and future generations. To learn more about the Project Gutenberg Literary Archive Foundation and how your efforts and donations can help, see Sections 3 and 4 and the Foundation web page at https://www.pglaf.org.

Section 3. Information about the Project Gutenberg Literary Archive Foundation

The Project Gutenberg Literary Archive Foundation is a non profit 501(c)(3) educational corporation organized under the laws of the state of Mississippi and granted tax exempt status by the Internal Revenue Service. The Foundation's EIN or federal tax identification number is 64-6221541. Its 501(c)(3) letter is posted at https://pglaf.org/fundraising. Contributions to the Project Gutenberg Literary Archive Foundation are tax deductible to the full extent permitted by U.S. federal laws and your state's laws.

The Foundation's principal office is located at 4557 Melan Dr. S. Fairbanks, AK, 99712., but its volunteers and employees are scattered throughout numerous locations. Its business office is located at 809 North 1500 West, Salt Lake City, UT 84116, (801) 596-1887, email [email protected]. Email contact links and up to date contact information can be found at the Foundation's web site and official page at https://pglaf.org

For additional contact information: Dr. Gregory B. Newby Chief Executive and Director [email protected]

Section 4. Information about Donations to the Project Gutenberg Literary Archive Foundation

Project Gutenberg-tm depends upon and cannot survive without wide spread public support and donations to carry out its mission of increasing the number of public domain and licensed works that can be freely distributed in machine readable form accessible by the widest array of equipment including outdated equipment. Many small donations ($1 to $5,000) are particularly important to maintaining tax exempt status with the IRS.

The Foundation is committed to complying with the laws regulating charities and charitable donations in all 50 states of the United States. Compliance requirements are not uniform and it takes a considerable effort, much paperwork and many fees to meet and keep up with these requirements. We do not solicit donations in locations where we have not received written confirmation of compliance. To SEND DONATIONS or determine the status of compliance for any particular state visit https://pglaf.org

While we cannot and do not solicit contributions from states where we have not met the solicitation requirements, we know of no prohibition against accepting unsolicited donations from donors in such states who approach us with offers to donate.

International donations are gratefully accepted, but we cannot make any statements concerning tax treatment of donations received from outside the United States. U.S. laws alone swamp our small staff.

Please check the Project Gutenberg Web pages for current donation methods and addresses. Donations are accepted in a number of other ways including including checks, online payments and credit card donations. To donate, please visit: https://pglaf.org/donate

Section 5. General Information About Project Gutenberg-tm electronic works.

Professor Michael S. Hart was the originator of the Project Gutenberg-tm concept of a library of electronic works that could be freely shared with anyone. For thirty years, he produced and distributed Project Gutenberg-tm eBooks with only a loose network of volunteer support.

Project Gutenberg-tm eBooks are often created from several printed editions, all of which are confirmed as Public Domain in the U.S. unless a copyright notice is included. Thus, we do not necessarily keep eBooks in compliance with any particular paper edition.

Most people start at our Web site which has the main PG search facility:

https://www.gutenberg.org

This Web site includes information about Project Gutenberg-tm, including how to make donations to the Project Gutenberg Literary Archive Foundation, how to help produce our new eBooks, and how to subscribe to our email newsletter to hear about new eBooks.