SCIENTIFIC FAITH 



as they were before the agents of erosion had so 

 widely severed them. 



These physical forces have worked as slowly and 

 silently in sculpturing the landscapes as the biolo- 

 gical laws have worked in evolving man from the 

 lower animals, or the vertebrates from the inverte- 

 brates. The rains, the dews, the snows, the winds 

 — how could these soft, gently careering agents have 

 demolished these rocks and dug these valleys? One 

 would almost as soon expect the wings and feet of 

 the birds to wear away the forests they flit through. 

 The wings of time are feathered also, and as they 

 brush against the granite or the flinty sandstone no 

 visible particle is removed while you watch and 

 wait. Come back in a thousand years, and you note 

 no change, save in the covering of trees and verdure. 

 Return in ten thousand, and you would probably 

 find the hills carrying their heads as high and as 

 proudly as ever. Here and there the face of the cliff 

 may have given way, or a talus slid into the valley, 

 or a stream or river changed its course, or sawed 

 deeper into the rock, and a lake been turned into a 

 marsh, or the delta of a river broadened — minor 

 changes, such as a shingle from your roof or a brick 

 from your chimney, while your house stands as be- 

 fore. In one hundred thousand years what changes 

 should we probably find? Here in the Catskills, 

 where I write, the weathering of the hills and moun- 

 tains would probably have been but slight. It must 



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