Where did Life Begin f ij 



less matter to cool, and have radiated heat 

 into space more rapidly in proportion to mass 

 than the equatorial belt or any other parts of 

 the earth's surface. In the light of these facts 

 it seems to me the following conclusions can- 

 not be well avoided : 



First, — That the polar zones having led the 

 advance in cooling, have had in turn all the 

 temperatures, climates, and climatic conditions 

 which at any time the torrid and temperate 

 zones have had, in addition to long later 

 periods of cooler temperature and climates 

 than either. 



Second. — Therefore, that at one epoch or 

 another the polar regions of the earth have 

 enjoyed all the various temperatures and cli- 

 matic conditions necessary to maintain all the 

 well nigh infinite forms of life, both vegetal and 

 animal, which are now, or ever have been, 

 upon this globe. At the risk of being tedious 

 let us state this hypothesis in another way. 



The whole globe was once a molten mass 

 too hot to maintain life. The polar regions 

 were then too hot for that purpose. These 

 same regions are now too cold to maintain 



