As I had proved from matter of fact, or the actual appearances of nature, that all the strata of the earth had been formed at the bottom of the sea, by the subsidence of those materials which either come from the decaying land, or are formed in the sea itself, it was necessary that I should consider in what manner those spongy or porous bodies of loose materials, gathered together at the bottom of the sea, could have acquired that consolidated state in which we find them, now that they are brought up to our examination.  Upon this occasion, our author says, “The particles which now form the solid parts of the globe need not be supposed to have originally been either spongy or porous, the interior parts at the depth of a few miles might have been originally, as at present, a solid mass.”  If, indeed, we shall make that supposition, we may then save ourselves the trouble of considering either how the strata of the earth have been formed or consolidated; for, they might have been so originally.  But, how can a naturalist who had ever seen a piece of Derbyshire marble, or any other shell limestone, make that supposition?  Here are, to the satisfaction of every body of common understanding who looks at them, bodies which are perfectly consolidated, bodies which have evidently been formed at the bottom of the sea, and therefore which were not originally a solid mass.  Mr Bertrand, it is true, wrote a book to prove that those appearances were nothing but a lusus naturae; and, I suppose he meant, with our author, that those strata had been also originally, as at present, a solid mass.

With regard to the consolidation of strata, that cardinal point for discussion, our author gives the following answer:  “Abstracting from his own gratuitous hypothesis, it is very easy to satisfy our author on this head; the concreting and consolidating power in most cases arises from the mutual attraction of the component particles of stones to each other.”  This is an answer with regard to the concreting power, a subject about which we certainly are not here inquiring.  Our author, indeed, has mentioned a consolidating power; but that is an improper expression; we are here inquiring, How the interstices, between the collected materials of strata, deposited at the bottom of the sea, have been filled with a hard substance, instead of the fluid water which had originally occupied those spaces.  Our author then continues; “If these particles leave any interstices, these are filled with water, which no ways obstructs their solidity when the points of contact are numerous; hence the decrepitation of many species of stones when heated.”