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the other, it shall be a confused jumble of stones of every denomination. *

It has also been asserted, that when we see the same strata in the opposed sides of different mountains, we should infer, that the matter of these strata were once continuous. The same inference should be made, it is also said, when we see the chalky clifts as of Dover, on the one side, corresponding with those of Calais on the other; Justin says,

“ Siciliam ferunt “ angustis quondam faucibus Italiæ adhæsisse,

direptamque velut a corpore majore impetu

superi mari, quod toto undarum onere illuc “ vehitur.” Many strata, indeed, have been indisputably continued, which are now no longer so, but whose intermediate parts have been removed by violence or other causes : but, at the same time, that this may be admitted, that mountains are natural productions in the ocean, it is not at the same time to be argued, that vallies are adventitious ones out of the

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ocean,

In the course of his voyages, the very able Captain Cooke thought le had reason to be of opinion, that some of the islands discovered in

the

* De Saussure.

the Pacific Ocean, were formed by the slow growth of coral rock, and the gradual accession of sand and shells. They were observed in every state of their progress; some, which were arrived at their highest maturity, and were covered with vegetables, had only a very thin layer of mould, immediately under which the coral rock appeared in every part of them. Others

. were but just risen above the level of the sea, some of which had very few, and others no vegetables at all. On one of these, called Palmerston's Island, a few cocoa-nut trees and other plants were just seen sprouting up, a few inches above where the sea had reached; and on others, the various plants, which grew nearest to the shore, were in lines parallel to it, and evidently arose from seeds brought thither by the sea.

From this, a deduction I think is warrantably to be drawn; that if the waters were, by any means, to be separated from these islands in the southern hemisphere, the islands would then become mountains, and their vallies would be found to have been naturally formed in the bosom of the same ocean, and at the very same period of time. It may be urged, indeed, on the other side, that in the highest parts of the vallies, surrounded by the highest Alps, one A 3

does rivers

does not meet with rounded flints. They are strangers, it is said, to those parts; whereas, in the plains, and in the entrances of these vallies, and even on the tops of mountains which surrounds these plains, such quantities of them are found, that an unenlightened man would suppose they had tumbled from Heaven. * Now it is a fact, that these fints are of a nature totally different from the stones which are found to be in their neighbourhood. What can they be else then, (it is asked) but the wrecks of other parts? To this I will not answer, as others have done, that rounded Aints do not receive their forms by attrition only, but, that they have been rounded in their original structure in the beds of matter, from which the waters, or, revolutions of the earth, have at some distant period separated them : nor will I say, that they were originally created in nodular forms, attrition by water probably injuring their surface; but, certainly, not being the cause of their forms. The fints which are so universally picked up in the Alps, I can readily conceive to have been detached from mountains very distant from them, and that they have been smoothed and rounded by the waters. Naturalists who travel over high mountains, or where

* De Saussure,

ness.

spot which

rivers take their source, clearly perceive how stones naturally angular, lose their angles; and as it were under their eye, assume a round

The shores of the sea and lakes shew, likewise, the same transformation by the power of the waves; as the lava of Ætna does, which rushes into the sea. Granite, marble, jasper, &c. which are the substances of most flints that are rounded, looked at in the

produce them, are never found rounded. The beds on which flints are generally deposited are calcareous, and consequently of an apparently different nature ; nay, it is evident, that they have no adherence to the soil on which they are thrown, and that they have no resemblance to the earth which surrounds them. Moreover, there is nothing but water, which in diminishing their weight, could have laid them with the lightness with which they have all evidently been deposited. Had they rushed through the air upon a volcanic hypothesis, and to have fallen only eight or ten feet, they would have been buried to a considerable depth.

My argument goes not so far, as to deny the power of the waters in their retreat ; on the contrary, I warmly contend for it: I only mean to say, that there does not appear a necessity. why the vallies should not have been formed when the mountains were ; nor a very philosophical reason, why the waters in their subsiding from the surface of the earth, should have had force sufficient to have excavated piles of granite of an enormous height, and that in a space of time, too scanty even for the formation of the channel of a brook : and these difficulties are moreover strengthened, by the confession of naturalists themselves, who allow, that the bottom of many of these vallies is of the primordial granite itself, while many of the smaller sized . incumbrances with which they are loaded, are secondary or calcareous.

These mountains and vallies of granite, therefore, we must conclude, were formed at the same period, and by the same cause.

The waters were the medium, whence the component particles were derived, and crystallization effected the mighty work : but, all this reasoning, you will say, has been denied; fire, you

will
say,

has been the powerful agent, on which some of the ablest philosophers have wished to rest their system of mountains. On this subject, we will not argue at present: I will not concede the ground; and yet, it would be ridiculous to deny

the

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