Sixteenthly. There is evidence, in regard to some parts of the world, that the continents are now experiencing slow vertical movements--some places sinking, and others rising. And hence a presumption is derived that, in early times, such changes may have been often repeated, and on a great scale. Seventeenthly. Every successive change of importance on the earth's surface appears to have been an improvement of its condition, adapting it to beings of a higher organization, and to man at last, the most perfect of all. Finally. The present races of animals and plants on the globe are for the most part disposed in groups, occupying particular districts, beyond whose limits the species peculiar to those provinces usually droop and die. The same is true, to some extent, as to the animals and plants found in the rocks; though the much greater uniformity of climate, that prevailed in early times, permitted organized beings to take a much wider range than at present; so that the zoological and botanical districts were then probably much wider. But the general conclusion, in respect to living and extinct animals, is, that there must have been several centres of creation, from which they emigrated as far as their natures would allow them to range. It would be easy to state more principles of geology of considerable importance; but I have now named the principal ones that bear upon the subject of religion. A brief statement of the leading truths of theology, whether natural or revealed, which these principles affect, and on which they cast light, will give an idea of the subjects which I propose to discuss in these lectures. The first point relates to the age of the world. For while it has been the usual interpretation of the Mosaic account, that the world was brought into existence nearly at the same time with man and the other existing animals, geology throws back its creation to a period indefinitely but immeasurably remote. The question is not whether man has existed on the globe longer than the common interpretation of Genesis requires,--for here geology and the Bible speak the same language,--but whether the globe itself did not exist long before his creation; that is, long before the six days' work, so definitely described in the Mosaic account? In other words, is not this a case in which the discoveries of science enable us more accurately to understand the Scriptures? The introduction of death into the world, and the specific character of that death described in Scripture as the consequence of sin, are the next points where geology touches the subject of religion. Here, too, the general interpretation of Scripture is at variance with the facts of geology, which distinctly testify to the occurrence of death among animals long before the existence of man. Shall geology here, also, be permitted to modify our exposition of the Bible?