This mode of accounting for the origin and formation of Stratified Rocks constitutes in a manner the framework that supports and binds together the whole system of Geology. If it be once fairly established, Geology is entitled to take high rank as a Physical Science. If on the contrary it should prove to be without foundation, then Geology is no longer a science, but a dream. Moreover, it is this theory of stratification which, from the first, has brought Geology into contact with Revelation. For Geologists have been led to infer the extreme Antiquity of the Earth, from the immense thickness of the Stratified Rocks on the one hand, and, on the other, the very slow and gradual process by which each stratum in the series has been, in its turn, spread out and consolidated. Those likewise who claim for the Human Race a greater Antiquity than the Bible allows, seek for their proofs in the supposed origin and antiquity of those superficial deposits, in which the remains of Man or of his works are sometimes found entombed. It is not to be wondered at, therefore, that the theory of Stratified Rocks should engage the largest share of our attention when we undertake to discuss the relation in which Geology stands to Revealed Religion. For the present we say nothing about the conclusions that flow from this theory, or the errors to which it has led when hastily or ignorantly applied: we are only investigating the evidence by which it is supported. In our former chapters we have drawn out at some length the line of reasoning which is derived from the character of the Aqueous Rocks themselves when considered in the light of Nature’s present operations. We have shown that Stratified Rocks of many different kinds, just such as those which compose the Crust of the Earth, have been produced by natural causes within historic times; and we have explained some of the more simple and intelligible parts of that complex machinery, which, even now, is busily at work gathering, sorting, distributing, piling up together, and consolidating the materials of new strata all over the world. These considerations, as we took occasion to point out, beget a strong presumption in favor of Geological theory. Here we have Nature at work, actually bringing into existence a stratum of rock before our eyes. And there, in the Crust of the Earth, we find another stratum of precisely the same kind already finished. What can be more reasonable than to ascribe the one to the action of the same causes which we see at work upon the other? And thus, by extending the area of our observations from one class of Aqueous Rocks to another, the idea gradually grows upon us that these rocks have been spread out, stratum upon stratum, during many successive ages, by the agency of secondary causes similar to those which are still in operation; and that each stratum, in its turn, as it first came into existence, was for a time the uppermost of the series.