175 



CH^P. XXIII. INORGANIC EVOLUTION FROM A CHEMICAL 

 STANDPOINT. 



IN the study of the -facts of inorganic evolution presented to us by 

 stellar spectra, there is one point of paramount importance to be in- 

 quired into. In the problems of inorganic evolution which we have 

 now to face, it is sufficiently obvious that we have to deal with a con- 

 tinuously increasing complexity of forms, precisely as in organic 

 evolution the biologist has had to deal, and has dealt successfully with, 

 a like increase of complexity of organic forms. 



So far the processes by which complexity has been brought about 

 have only been referred to generally ; it is time now to endeavour to 

 gain a more .detailed insight into the methods by which inorganic com- 

 plexity has been arrived at. I will discuss this question first in rela- 

 tion to chemical theory. 



If we ask the question How has complexity been brought about in 

 the case of .known chemical compound bodies 1 an easy answer is given 

 by analysis. -Chloride of sodium, for instance, is thus found to be 

 formed by the combination of chlorine and sodium. But when we wish 

 to deal with the formation of the so-called " elements " themselves, no 

 such easy solution of the question is open to us. 



If in order to investigate the problem we take the analogy furnished 

 by compound bodies as our guide, we should say that the molecules of 

 the elements themselves were produced by the combination of unlike 

 forms. 



But as a matter of fact, this method of producing complexity is 

 not the only one known to chemists. There are bodies of the same per- 

 centage composition which differ in molecular weight; the methane 

 series of hydrocarbons is a case in point ; the higher molecular weights, 

 or greater complexes, are produced by additions of the unit CH 2 , so 

 that these higher complexes are produced by the combination of 

 similar lower complexes. This process is termed polymerisation. 



We are then familiar with two methods of increasing complexity, 

 which we may represent by a + a (polymerisation) and x + y (combi- 

 nation), producing a form A. 



This, then, is the problem from the purely chemical side. On which 

 of these methods have the elements themselves been formed, now that 

 we are justified in considering them as compound bodies ? I suppose 



