AND MODEttN PHYSICS. 81 



impressed upon it the stamp of a metric system, as distinctly 

 as does the metro of the Archives at Paris, or the double royal 

 cubit of the temple of Karnac. 



"No theory of evolution can bo formed to account for the 

 similarity of molecules, for evolution necessarily implies con- 

 tinuous change, and the molecule is incapable of growth or 

 decay, of generation or destruction. 



44 None of the processes of Nature, since the time when 

 Nature began, have produced the slightest difference in the 

 properties of any molecule. Wo arc therefore unable to 

 ascribe cither the existence of the molecules or the identity 

 of their properties to any of the causes which we call natural. 



44 On the other hand, the exact equality of each molecule to 

 all others of the same kind gives it, as Sir Johu Ilerschel has 

 well said, the essential character of a manufactured article, 

 and precludes the idea of its being eternal and self-existent. 



"Thus we have been led along a strictly scientific path, 

 very near to the point at which Science mast stopnot that 

 Science is debarred from studying the internal mechanism of a 

 molecule which she cannot take to pieces any more than from 

 investigating an organism which she cannot put together. But 

 in tracing back the history of matter. Science is arrested when 

 she assures herself, on the one hind, that the molecule haa 

 been made, and, on the other, that it has not been made by 

 any of the processes we call natural. 



"Science is incompetent to reason upon the creation of 

 matter itself out of nothing. \Ye have reached the utmost 

 limits of our thinking faculties when we have admitted that 

 because matter cannot be eternal and self-existent, it must 

 have been created. 



" It is only when we contemplate, not matter in itself, but 

 the form in which it actually exists, that our mind tinds some- 

 thing on which it can lay hold. ~^ 



44 That matter, as such, should have certain fundamental 

 properties, that it should exist in space and be capable of 

 motion, that its motion should be persistent, and so on, are 

 truths which may, for anything we know, be of the kind which 

 metaphysicians call necessary. We may use our knowledge of 



F 



