CHAPTER II 

 ORGANIC EVOLUTION 



IN the earlier stages of the evolution of the earth 

 there could have been no organic forms, such as 

 we know them now. But if the nebular or plane- 

 tessimal theory is the correct one, there came a 

 time in the condensation of our globe, after it had passed 

 through a gaseous, and then assumed a comparatively 

 solid form, that the surface temperature became greatly 

 reduced. At some favorable juxtaposition of earth, air, 

 temperature, and moisture, life must have arisen from 

 inorganic substances in a manner entirely unknown to 

 us, except by scientific inference, no man being there to 

 see it ; at first in a very lowly form, by a combination of 

 elements which we find in all organisms, carbon, hydro- 

 gen, oxygen, and nitrogen. As shown heretofore, three 

 of these elements form a large part of the earth's crust, 

 and nitrogen is one constituent, very large in bulk, of the 

 inorganic atmosphere. The evolution of living forms, as 

 we now see them, from the first true moner, which per- 

 haps came into existence in a natural way in many places 

 at the same time, is what we mean by organic, or bio- 

 logical evolution, as distinguished from the older theory 

 of special creation. It followed after inorganic evolu- 

 tion, as a natural result of the upward, or progressive 

 change of matter, from the homogeneous to the hetero- 

 geneous. Life could not exist without the inorganic for 

 its support. It is never found except in contact with 

 matter, and its own form is always composed of inorganic 

 elements. The inorganic and the organic are never sepa- 

 rate. A life form is not made up of certain inorganic 



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