'HE THEORY OF MOLECULES. 289 



in Sirius 01 turus, executes its vibrations in precisely the same 



time. 



Each mokclc, therefore, throughout the universe, bears impressed 

 on it the sta ) of a metric system as distinctly as does the metre 

 of the Archivi of Paris, or the double royal cubit of the Temple of 

 Karnac. 



No theory t evolution can be formed to account for the similarity 

 of molecules, fi evolution necessarily implies continuous change, and 

 the molecule incapable of growth or decay, of generation or de- 

 struction. 



None of t 1 rocesses of Nature, since the time when Nature be- 

 gan, have prouced the slightest difference in the properties of any 

 molecule. W s re therefore unable to ascribe either the existence of 

 the molecules, r the identity of their properties, to the operation of 

 any of the can--; which we call natural. 



On the othr hand, the exact equality of each molecule to all others 

 of the same kin gives it, as Sir John Herschel has well said, the es- 

 sential charade of a manufactured article, and precludes the idea of 

 its being eterm and self-existent. 



Thus we ha ■; been led, along a strictly scientific path, very near 

 to the point 1 hich Science must stop. Not that Science is de- 

 barred from stuying the internal mechanism of a molecule which she 

 cannot take to leces, any more than from investigating an organism 

 which she cannc put together. But, in tracing back the history of 

 matter, Science ; arrested when she assures herself, on the one hand, 

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

 made by any olhe processes we call natural. 



Science is inompetent to reason upon the creation of matter itself 

 out of nothing. We have reached the utmost limit of our thinking 

 faculties when ■» have admitted that because matter cannot be eter- 

 nal and self-exbmt it must have been created. 



It is only who we contemplate, not matter in itself, but the form 

 in which it actutiy exists, that our mind finds something on which it 

 can lay hold. 



That mattei. s such, should have certain fundamental properties — 

 that it should ex;t in space and be capable of motion, that its motion 

 should be persismt, and so on, are truths which may, for any thing we 

 know, be of the ind which metaphysicians call necessary. We may 

 use our knowleoe of such truths for purposes of deduction, but we 

 have no data fou peculating as to their origin. 



But that thei should be exactly so much matter and no more in 

 every molecule c hydrogen is a fact of a very different order. We 

 have here a pantoular distribution of matter — a collocation — to use 

 the expression c >r. Chalmers, of things which we have no difficulty 

 in imagining to hve been arranged otherwise. 



The form an <. imensions of the orbits of the planets, for instance, 



VOL. I- -19 



