CHAPTER VI. THE TERTIARY SYSTEM. The Tertiary System forms the last great subdivision of the rocky strata of the earth—the last in the creative, as well as geographical, distribution of organic and inorganic matter—antecedent to the human epoch. All the European and partly Asiatic chains of mountains were again farther elevated toward the close of the preceding period. Europe itself assumed a more distinctive shape and contour, a bolder coast-line, higher plateaux, deeper and more extensive lakes. Great Britain was rounded into form, settled upon new foundations, and already stood out, in her western and northern belt of granitic and primary rocks, the empress of the ocean. In thus recalling the features of the old world, and marking the configuration of a newer state of things, geology furnishes indubitable evidence upon which to establish these and other more general conclusions. The physical geography of the globe is inseparably connected with the series of changes we have been contemplating. The elevation, small and isolated as it appears, of the formation termed the wealden, supplies a key by which to measure the rivers and deltas of our own island. The chalk, forming at the time the bed of the ocean, remained for a period in undisturbed repose, as evidenced by the hollows and erosive action seen on its surface. Then a series of convulsive movements, over a vast area, are indicated by the disrupted and altered position of the strata, when the bottom of the sea was lifted up, and its whole marine fauna completely changed. The secondary era passed away: the new tertiary arrangements, animate and inanimate, from henceforth commence. Thus rolls on the mighty course of time. A continent is the gift of one age: half a globe is shattered and wasted in the next. All living things become extinct and entombed in this quarter: in that, there are new and more abundant creations. The face of nature is again redolent with beauty: life, profusion, and enjoyment are everywhere abounding. “Look down on earth. What seest thou? Wondrous things, Terrestrial wonders that eclipse the skies. Nor can the eternal rocks His will withstand— What leveled mountains, and what lifted vales! High through mid air, here streams are taught to flow— Whole rivers there, laid by in basins, sleep— Here plains turn oceans; there vast oceans join, Through kingdoms, channel’d deep from shore to shore.”