TIME AND CHANGE 



hundred thousand times as long, this preceding 

 period, or great fall, was probably equally long 

 — so long that the whole of recorded human history 

 would form but a small fraction of it. It may easily 

 be, I think, that we are now Uving in the spring of the 

 great cycle of geologic seasons. The great ice-sheet 

 has withdrawn into the Far North like snowbanks 

 that linger in our wood in late spring, where it still 

 covers Greenland as it once covered this country. 

 When the season of summer is reached, some hun- 

 dreds of thousands of years hence, it may be that 

 tropical life, both animal and vegetable, will again 

 flourish on the shores of the Arctic Ocean, as it did 

 in Tertiary times. And all this change will come 

 about so quietly and so slowly that nobody will 

 suspect it. 



That the crust of the earth is becoming more and 

 more stable seems a natural conclusion, but that all 

 folding and shearing and disruption of the strata 

 are at an end, is a conclusion we cannot reach in the 

 face of the theory that the earth is shrinking as it 

 cools. 



The earth cools and contracts with almost infinite 

 slowness, and the great crustal changes that take 

 place go on, for the most part, so quietly and gently 

 that we should not suspect them were we present on 

 the spot, and long generations would not suspect 

 them. Elevations have taken place across the beds 

 of rivers without deflecting the course of the river; 



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