COSMIC EVOLUTION 



the nature of the sun's atmosphere. At the pres- 

 ent time in large part owing, it is of interest to 

 note, to the work of Professor George Darwin, 

 the son of the immortal Charles the nebular theory 

 is accepted by all astronomers save perhaps one. 

 In it you will find, on the largest scale, an illustra- 

 tion of inorganic evolution. Let us consider this 

 great theory as it is understood to-day, forty-seven 

 years after Herbert Spencer's bold defence of it, 

 contra mundum. 1 



Let us conceive, then, of an immense cloud or 

 nebula, situated at some point in infinite space 

 certainly far distant from the present position of 

 the solar system a position which, owing to the 

 "proper motion" of the sun, is changing at the 

 rate of nearly twelve miles a second as you read. 

 But before you are willing to follow the argument, 

 you will stop and ask where this nebula came 

 from; for you have already become convinced 

 of the laws of conservation; you know that the 

 nebula did not spring into existence out of nothing, 

 and you very properly decline to continue until 

 this most legitimate question is answered. You 

 quote that most ancient maxim of Ionian science, 

 "Ex nihilo nihil fit" an axiom which, nearly 

 twenty-five centuries after Thales, is now a proven 

 truth and demand to know where I get this 

 nebula of which I talk so glibly. But we must 



1 Some measure of justice was paid to his work in a lecture 

 on the nebulae delivered last year before the British Associa- 

 tion. 



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