Page:Popular Science Monthly Volume 4.djvu/736

716 Yet the modifications of opinion which appear to be demanded, on the ground of fact as well as on the ground of reason, will necessitate very considerable and almost revolutionary changes in the accepted code of biological doctrines.

An examination of the facts of science generally and of various every-day phenomena teaches us, according to the Evolutionist, that matter of different kinds, situated as it is and has been, gradually tends within certain limits to become more and more complex in its internal and external constitution. Coupling this conclusion with various astronomical data, with geological data, and with facts derived from the study of the past forms of Life upon our globe, the Evolutionist essays to penetrate through the long vista of by-gone ages, till he may rest his speculative gaze upon a vast rotating nebular mass of gaseous matter, of comparatively simple though unknown constitution, from which he supposes our Universe to have been slowly evolved. Without futile questionings as to the explanation or cause of the existence of the nebula, without speculation as to what simpler or more complex matter may have immediately preceded it, it is obvious that we may for our own convenience take up its imaginary existence at any stage. Though we must be free to admit that in concentrating our attention upon this nebular stage, or upon any other, we arbitrarily break into a mysterious cycle of existence whose Cause is to us unfathomable. It is needless for my purpose, however, to attempt to concentrate the reader's attention upon a period so remote in the history of our Universe. The primordial nebula, as it cooled and condensed, acquired a more rapid axial rotation: masses were gradually thrown off from its circumference, and these in their turn condensed into rotating spheroids, which continued to circulate round the parent mass in elliptical orbits. Assuming, then, with the Evolutionist, that our own planet had a past history of this kind, we must also assume that it gradually changed from a gaseous to a fluid state before beginning to solidify by the formation of a superficial crust—a crust which gradually thickened as the fervent heat of it and of the fluid nucleus abated by heat-radiations into space. Until this stage of the Earth's history had been far advanced, no Living Things could have existed upon its surface. "Hence," as Sir William Thomson said, "when the Earth was first fit for life there were no living things on it. There were rocks, solid and disintegrated, water, air all round, warmed and illuminated by a brilliant sun, ready to become a garden." Living things must, however, have appeared upon its surface at some very remote epoch, since their remains are to be found far down in the rocks which at present constitute its crust. But how, it must be asked, is the first appearance of living matter upon the earth to be accounted for?

We should not needlessly invoke an abnormal act of Creative