64 UNIVERSAL EVOLUTION 



ten thousand five hundred years. That is, a glacial 

 epoch follows another in the northern hemisphere in 

 about twenty-one thousand years ; and also in the 

 southern hemisphere in the same time, but each will 

 come between the time of the other. This time cor- 

 responds with the revolution of the north magnetic 

 pole of the earth about the point in the universe toward 

 which it apparently points. This revolution is made 

 in twenty-one thousand years. At opposite points of 

 this orbit, first one hemisphere, and then the other, of 

 the earth, is so shut out from the heat of the sun, and 

 the earth's orbit becomes so eccentric, and so affects 

 ocean currents, as to produce a glacial epoch. During 

 the glacial epoch in one hemisphere, the other has a 

 milder climate than the normal. This is a very curious 

 and important fact. These alternate cold epochs must 

 have a radical effect upon all life upon the globe. 



MAN'S DISTRIBUTION. Geographical distribution is 

 illustrated by the way man has spread over the earth. 

 He is the animal which travels most, goes the far- 

 thest, climbs the highest, burrows the deepest. He 

 is able to build vehicles on land, tame the horse, and 

 the ox, and teach them to pull himself and vehicles to 

 whatever point he desires to reach. He can construct 

 boats on the water, and propel them by steam engines 

 to the remotest parts of the earth. When a region be- 

 comes too thickly inhabited, the young men and 

 women emigrate to other regions less occupied, or not 

 inhabited at all. It is notorious how those emigrants 

 from Europe and Asia are now (1912) flocking to the 

 United States, and how markedly their physical, and 

 mental characters change in the new environment, 

 especially in the second, and subsequent generations. 

 These changes are favorable variations in their struggle 



