TIME AND CHANGE 



where we now stand two or more miles of strata have 

 been worn away by the winds and rains; that the soil 

 of our garden, our farm, represents the ashes of moun- 

 tains burned up in the slow fires of the geologic ages. 



Geology first gives us an adequate conception of 

 time. The limitations which shut our fathers into 

 the narrow close of six thousand years are taken 

 down by this great science and we are turned out 

 into the open of unnumbered millions of years. Upon 

 the background of geologic time our chronological 

 time shows no more than a speck upon the sky. 

 The whole of human history is but a mere fraction 

 of a degree of this mighty arc. The Christian era 

 would make but a few seconds of the vast cycle of 

 the earth's history. Geologic time! The words seem 

 to ring down through the rocky strata of the earth's 

 crust; they reverberate under the mountains, and 

 make them rise and fall like the waves of the sea; 

 they open up vistas through which we behold the 

 continents and the oceans changing places, and the 

 climates of the globe shifting like clouds in the sky; 

 whole races and tribes of animal forms disappear 

 and new ones come upon the scene. Such a past ! 

 the imagination can barely skirt the edge of it. 

 As the pool in the field is to the sea that wraps the 

 earth, so is the time of our histories to the cycle of 

 ages in which the geologist reckons the events 

 of the earth's history. 



Through the eyes of the geologist one may look 



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