12 THE CKEED OF SCIENCE, EELIGIOUS AND MORAL. 



heat, which was assumed by Laplace ; and it explains 

 it by a true scientific cause the impact of masses in 

 motion. Moreover, by a still bolder application of the 

 same conception, and for the first time, we might almost 

 say, since men began to speculate on the matter, it ex- 

 plains in a real way, the actual presence of our old solid 

 earth here in space to-day. It is true that the explana- 

 tion given the sudden convergence from the four winds 

 of the materials of our globe is at first a little startling, 

 and almost as trying to the imagination as the old theory 

 of creation ex nihilo. But on reflection we see that the 

 thing is possible, the conception scientific. If we believe 

 our earth to be a globe in space, we must allow that 

 its materials, as well as those of every other heavenly 

 body, may have come thus together from a state of 

 nebular or meteoric dispersion, under the strong com- 

 pulsion of gravitation ; and it may have even been, as 

 Professor Tait suggests, " that they fell together in such 

 a way that the whole mass of the earth was agglome- 

 rated together almost at once." 



We might, I say, even believe in this instantaneous 

 fusion and chemical union following on the mechanical 

 forcing together of the materials, since the chemical 

 change, on the vast scale of a given mass of loose 

 materials into a molten planet, may be quite as easy for 

 Nature to effect as the chemical changes on the small 

 scale in her ordinary operations. It is only when we 

 ask the inevitable further question Whence came the 

 materials that thus suddenly met together one day for 

 the composition of our globe ? that the theory begins to 

 prove unsatisfactory. For it appears from Sir W. Thom- 

 son's expositor, Professor Tait, that the precipitated sub- 

 stances came from, or rather formerly composed, a smaller 

 nebulous cloud that had become severed from the primi- 



