For ourselves, therefore, we frankly avow that while we attach but little importance to the mere conjectures and speculations of Geological writers; while we look with doubt and suspicion on many plausible theories commonly enough adopted at the present day; and while we consider that the discoveries of modern times, wonderful though they are, have given rise to far more problems than they are yet able to solve; yet we do fully assent to those general principles which we have been attempting to develop and to illustrate in this Volume. Absolutely metaphysical certainty we have not; but we have a firm and rational conviction. We feel quite satisfied that the great Creator of the Universe did not bring suddenly into existence the withered remains and broken fragments of animals which had never lived; that He did not stamp upon the massive rocks, buried in the profound recesses of the earth, the impress of a luxuriant vegetation which had never flourished; that He did not, in short, create under millions of forms, the delusive appearances of things which had never been, and scatter them through this world of ours in wild profusion, well knowing that after many centuries they would come to light to bewilder human reason, and to lead it into error. This conclusion, of course, we are prepared to abandon if it should be found to clash with any certain truth or with any demonstrated fact. But, in the mean lime, it seems to us as well grounded and as fairly established as the conclusions we are accustomed to accept without hesitation in the matter of other sciences, and in the common business of life. It is argued, however, that Geological theory is, in fact, at variance with the very highest order of truth; with that truth which comes to us on the authority of God Himself. The Bible tells us that the world first came into existence about six or eight thousand years ago: Geology, on the contrary, tells us that six or eight thousand years are but as yesterday in the history of the revolutions through which our Globe has passed. This is the argument to which we are now about to address ourselves; and it well deserves our best attention, not only from its intrinsic importance, but also from the interesting nature of the discussion to which it has given rise. In the first place, we fully admit that the extreme Antiquity of the Earth is a necessary consequence of our theory. Setting out from the present stage of the world’s existence, Geology carries us back from epoch to epoch, through a long succession of ages, each extending over many thousand years, until the mind is lost in the seeming infinity of the past. It may be asked, perhaps, in what way Geology can testify to the great length of each successive period in the history of the Globe. A familiar example will furnish the most convenient reply to such a question.