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 athousand 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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