Page:Popular Science Monthly Volume 11.djvu/693

Rh all the processes of concentration, of differentiation of parts, and of integration of the whole, as well as those of equilibration, of decomposition, and final dissolution. Not so with the planet. Whatever theory may suggest or require, we are forced to confess a profound ignorance of the final destiny of worlds. So far as we are able to observe, the universal tendency of all matter is from the indefinite and homogeneous to the definite and heterogeneous; from a state of unstable to one of stable equilibrium. But this is only the morning of the life of any aggregate. We have no reason to suppose that, in all the myriad worlds of visible space, a single star presents to our gaze a condition representing the evening of its life. In the light of all our knowledge of the heavenly bodies and of the nebulæ, we study with absorbing interest the history of our own planet. From the confused gaseous condition in which it is supposed to have originally been, its motion has been gradually dissipated and its matter integrated, until only a comparatively thin envelope of gas—the atmosphere—remains. The rest has all assumed either the liquid or the solid form, the latter of which presents the nearest approach to complete stable equilibrium. And it can scarcely be doubted that this process still continues, and will continue, until ultimately this omnipresent eremacausis shall also reduce the waters and the atmosphere to the condition of stability and solidification—a state of planetary existence which many suppose our satellite to have already reached.

And may not this same law be called in to explain the heterogeneity of elementary matter, as known to chemistry? If all matter is primordially identical, as so many philosophers have dreamed, is it not philosophical to assume that our sixty-five known elements represent so many states of heterogeneity, so many distinct kinds of primary aggregates, which the matter of our globe and other worlds has taken on in its course from complete homogeneous instability toward its ultimate condition of stable equilibrium, as represented in what we know as solids?

However this may be, it is at least true that, so far as regards purely cosmical processes, the ascending series is the only one observable by us. For the "dead star," be it understood, represents, in the grand cycle of the redistribution of matter and motion, the meridian of its life, and not its close. Complete equilibration is the last act in the drama of evolution, and must be attained before the forces of dissolution commence their work. But we look in vain for any signs of the dissolution of the universe. Whatever theory may require, the fact ever remains that the process which we see going on in our portion of space is the process of evolution only. We see only the integration of matter and the dissipation of motion. We see only the tendency toward the condition of stable equilibrium. We see only the absorption of the gaseous and the establishment of the solid form of matter. All the theories by which it has been sought to