We may now conclude this part of the subject, there fore, by remarking, that whatever difficulty may be found in particular cases, in explaining these alternations and mixtures of marine and terrestrial bodies, there appears none with respect to the general principles which thus point out to us changes in the relative level of the sea and land. The geologist who may attempt the solution of these specific cases must have recourse to these princi ples; and by combining them justly with the appearances, he will probably succeed in explaining cases which we can only pretend to notice in this most general manner.
On she Geological Causes of the Phenomena that attend Organic Remains.
We must now give a general sketch of those geologi cal changes or circumstances to which so many of the phenomena which attend fossil remains are owing. This, however, can only be slight, as to examine the whole at length would be almost to write a system of geology.
The circumstances that attend the most ancient strata, or the primary, prove that these have undergone one great disturbance, by which they have been elevated from their original submarine situations; when taken in combination with the appearances of the secondary, or more recent strata that lie on these, they prove that the present situa tion of the most ancient strata is the result of two distur bances or revolutions. In these strata, there are contain ed the most ancient inhabitants of the globe, of which we have, or can acquire, any knowledge. That there has been one revolution, at least, prior even to the first of these, has been inferred by Dr. Hutton in his celebrated
theory ; but such and so minute are the circumstances by which it is supposed to be demonstrated, that we cannot expect that it should yield any evidences of a creation so remote, even if such a one should have existed. We are therefore entitled to neglect it altogether, as too hypothe tical in its nature to permit any reasoning respecting it.
The fossil remains of the primary strata constitute, therefore, to us, the earliest creation of animated beings. That many animals have been destroyed by the first of these revolutions, is unquestionable, as, in many places, those that were living must have been raised above the waters, together with those whose spoils were already im bedded in rocks, or in materials of a looser character. Whether that revolution was attended by a total destruc tion of the whole of that early creation, is a question that we cannot solve, and which, as far as any light can be thrown on it, has been already examined. It depends, in a great measure, on the change which the ocean must have undergone, and that principally in respect to tem perature; a subject on which it seems impossible to come 'co any decision. It is scarcely requisite to observe, that we here proceed on the ground that the land has been elevated, and not the sea removed; coinciding in that view with De Luc, Saussure, Lazzaro Moro, Hutton, and Play fair. The reasons for adopting this view of the subject will be fully given hereafter in our article on THEORIES