TIME AND CHANGE 



of Yosemite downward is an open valley strewn 

 with huge angular granite rocks and shows no signs 

 of glaciation whatever. The reason of this abrupt- 

 ness is quite beyond my ken. It is to me a plausible 

 theory that when the granite that forms the Sierra 

 was lifted or squeezed up by the shrinking of 

 the earth, large fissures and crevasses may have 

 occurred, and that Yosemite and kindred valleys 

 may be the result of the action of water and ice in 

 enlarging these original chasms. Little wonder that 

 the earlier geologists, such as Whitney, were led to 

 attribute the exceptional character of these valleys 

 to exceptional and extraordinary agents — to sudden 

 faulting or dislocation of the earth's crust. But 

 geologists are becoming more and more loath to call 

 in the cataclysmal to explain any feature of the topo- 

 graphy of the land. Not to the thunder or the light- 

 ning, to earthquake or volcano, to the forces of 

 upheaval or dislocation, but to the still, small 

 voice of the rain and the winds, of the frost and the 

 snow, — the gentle forces now and here active all 

 about us, carving the valleys and reducing the 

 mountains, and changing the courses of rivers, — 

 to these, as Lyell taught us, we are to look in nine 

 cases out of ten, yes, in ninety-nine out of a hun- 

 dred, to account for the configuration of the con- 

 tinents. 



The geologists of our day, while not agreeing as 

 to the amount of work done respectively by ice and 



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