Where did Life Begin? 21 



zones before any movement, and ])robably be- 

 fore the equatorial belt was cool enough to 

 maintain life, certainly before the first torrid 

 climates near the poles became cold enough 

 to exclude it. We may therefore safely con- 

 clude, if the code of natural laws has been uni- 

 formly in force — 



First. — That life commenced on those parts 

 of the earth which were first prepared to 

 maintain it ; at any rate, that it never could 

 have commenced elsewhere. 



Second. — As the whole earth was at one 

 time too hot to maintain life, so those parts 

 were probably first prepared to maintain it 

 which cooled first. 



Third. — That those parts which received 

 the least heat from the sun, and which radiat- 

 ed heat most rapidly into space, in proportion 

 to mass, and had the thinnest mass to cool, 

 cooled first. 



Fourth. — That those parts of the earth's 

 surface, and those only, answering to these 

 conditions, are the arctic and antarctic zones. 



Fifth. — That as these zones were at one 

 time too hot, and certain parts thereof are 



