Theory of the Earth, Volume 2 (of 4) eBook

This eBook from the Gutenberg Project consists of approximately 375 pages of information about Theory of the Earth, Volume 2 (of 4).

Theory of the Earth, Volume 2 (of 4) eBook

This eBook from the Gutenberg Project consists of approximately 375 pages of information about Theory of the Earth, Volume 2 (of 4).

“Mais ce dont on peut etre certain, c’est que, si les montagnes qui bordent ces deux rives de la vallee du Rhone, 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 vallees qui les separent ne se correspondent pas non plus.  Ce defaut de correspondance me paroit encore reveiller l’idee 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.

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Theory of the Earth, Volume 2 (of 4) from Project Gutenberg. Public domain.