SCIENCE 



continents, of extensive inland seas, of vast calca- 

 reous deposits, of slow sedimentation, and exten- 

 sive consumption of carbon dioxide. Most of the 

 western coal measures were laid down during this 

 age. With the reelevation of the land, the age of 

 huge reptiles — the dinosaurs, the mesosaurs, the 

 gigantic marine lizards — came to an end, and the 

 period of mammalian life, the Tertiary, came in. 

 During this period the borders of the continent, 

 here and there, were under the ocean, from New 

 Jersey southward, including the whole of Florida 

 and a large part of the Gulf States and of Texas, 

 but the interior of the continent was at last stable, 

 and the sea never again encroached upon it. 



If the parts of the watch had an attraction for 

 one another analogous to that of chemical aflanity, 

 or analogous to that which prevails among persons, 

 it is not incredible that a watch might result; or if 

 the letters of the alphabet, or if w^ords had attrac- 

 tions for one another, intelligent sentences might 

 result. The organs of the living body certainly have 

 no attraction for one another, yet here they are 

 working together to a single end. But to make a 

 watch, even if the different parts attracted one an- 

 other, must there not be an organizing principle — 

 something to make the watch a unit? 



Chemical aflinity results in water, it results in 

 the nitrates, the carbonates, the hydrates, but no 



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