Thus also the argument by which the Neptunists would connect the creation of fish with the beginning of the secondary mountains, falls entirely to the ground. Indeed, it is strange that Mr Kirwan should have supposed it possible, that the shells in question were loose and unconnected with the rock, and had continued so, ever since the deluge, in such elevated ground, where the torrents wear and cut down the mountains with unexampled violence, and have hollowed out _Quebradas_ so much deeper and more abrupt than the glens or vallies among other mountains. He had not, I believe, seen the passage I have quoted from Ulloa; but the circumstances did not warrant the shells in question to be regarded as extraneous and adventitious fossils. A geologist should have known better than to suppose this possible. When we see VOLTAIRE ascribing to accidental causes the transportation of those shells which he had been told were often found among the Alps, we can excuse in a Poet and a Wit, that ignorance of the facts in mineralogy, which concealed from him the extreme absurdity of his assertion; but when a Chemist or Mineralogist talks and reasons in the same manner, we cannot consider him as entitled to the same indulgence. NOTE XI. § 42. _Fracture and dislocation of the strata._ 182. The greatest part of the facts relative to the fracture and dislocation of the strata, belongs to the history of veins. The instances of slips, where no new mineral substance is introduced between the separated rocks, are what properly belong to this place. The frequency of these, and their great extent, are well known wherever mines have been wrought. In some of them no opening is left, but the slipped strata remain contiguous; in other cases, there is introduced an unconsolidated earth, often a clay, which may be supposed to have come from above, arid very probably to have been carried down by the water. In some such cases, however, there are not wanting appearances, which show the matter in the slip to have been forced up from below, as we find it to contain substances which could not have come from the surface.[91] [Footnote 91: Unconsolidated earth contained between the sides of a rock that has slipped, is frequent in Cornwall, and is called a _Fleukan_. ]