accompanied by destruction rapid and complete in a corresponding degree, since in this way the greatest amount of happiness is ensured, and the pain of misery and slow decay of the vital powers prevented. All nature, both living and extinct, abounds with facts proving the truth of this view; and it would be as unreasonable to doubt the wisdom and goodness of this arrangement, as it would be to call in question the mutual adaptation of each part in the great scheme of creation. No one who examines nature for himself, however superficially, can doubt the latter; and no one certainly, who duly considers the laws ordained for the general government of the world, can believe it possible for these laws to have acted without a system of compensation, according to which the vital energies of one tribe serve to prepare food for the development of higher powers in another.”[103] CHAPTER XI. SECONDARY ROCKS. _No. 5. The Chalk._ THE CRETACEOUS SYSTEM. “His hands formed the dry land.”—DAVID. At the conclusion of the Wealden period, the crust of our globe underwent another great change. The fresh-water rocks we have just been studying were probably submerged by some violent subterranean or subaquean agency, and upon a great part of them a new deposit was gradually formed. Foot by foot, and inch by inch, slowly accumulated those cretaceous particles (Lat. _creta_, chalk) which now constitute the chalk hills and cliffs of our own country, to say nothing of the extent of territory in Europe occupied by this well-known mineral. To those who like ourselves live in a chalk district, this formation possesses special interest, simply because the “bounds of our habitation” are fixed there; and though we miss here all traces of the Ichthyosaurus and Iguanodon, although no Deinotherium nor Mastodon as yet make their appearance on the stage of being, yet with a very little knowledge of geology, coupled with a desire not to walk through the world with “eyes and no eyes,” it is in our power to invest many an otherwise motiveless walk with pleasurable interest. A cutting in the hills may reveal some unthought-of geological curiosity; a heap of flints may disclose some “rich and rare” fossils; and even a walk over the Downs, those breezy “downs” or “heaths” of southern England, covered with their short herbage, and dotted with their browsing sheep—those downs that undulate in such well-known forms of beauty, may be fruitful of suggestions concerning their origin, character and antiquity, that may be of healthful power in the development of an intellectual life.