This vitality is not due, as seems commonly imagined, to the earth’s internal heat. Rather the earth’s internal heat is due to the vitality with which her frame is instinct. The earth’s vitality is in reality due to the power of attraction which resides in every particle of her mass—that wonderful force of gravitation, omnipresent, infinite in extent, the property whose range throughout all space should have taught long since what science is teaching now (and has been foolishly blamed for teaching), the equally infinite range of God’s laws in time also. By virtue of the force of gravity pervading her whole frame, the crust of the earth is continually undergoing changes, as the loss of heat and consequent contraction, or chemical changes beneath the surface, leave room for the movement inward of the rock-substances of the crust, with crushing, grinding action, and the generation of intense heat. If the earth’s energy of gravity were lost, the internal fires would die out—not, indeed, quickly, but in a period of time very short compared with that during which, maintained as they constantly are by the effects of internal movements, they will doubtless continue. They are, in a sense, the cause of earthquakes, volcanoes, and so forth, because they prepare the earth’s interior for the action of her energies of attraction. But it is to these energies and the material which as yet they have on which to work, that the earth’s vitality is due. She will not, indeed, retain her vitality as long as she retains her gravitating power. That power must have something to work on. When the whole frame of the earth has been compressed to a condition of the greatest density which her attractive energies can produce, then terrestrial gravity will have nothing left to work on within the earth, and the earth’s globe will be to all intents and purposes dead. She will continue to exercise her attractive force on bodies outside of her. She will rotate on her axis, revolve around the sun, and reflect his rays of light and heat. But she will have no more life of her own than has the moon, which still discharges all those planetary functions.
But such disturbances as the recent earthquakes, while disastrous in their effects to those living near the shaken regions, assure us that as yet the earth is not near death. She is still full of vitality. Thousands—nay, tens, hundreds of thousands of years will still pass before even the beginning of the end is seen, in the steady disintegration and removal of the land without renovation or renewal by the action of subterranean forces.—_The Contemporary Review._