COSMIC PHILOSOPHY 



of our planet. At a remote era in that history, 

 the differentiation and integration of solar radi- 

 ance began gradually to constitute the most im- 

 portant part of the complex process of terrestrial 

 evolution. We have now to show how this has 

 been done ; and we shall find it desirable to 

 introduce the subject with an inquiry into the 

 Sources of Terrestrial Energy. 



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