MOUNTAINS AND HILLS 



215 



manner, except that the bulge or uplift was 

 more abrupt from being localized within a com- 

 paratively small area. 



It is popularly supposed that the Alps, the 

 Himalayas, the Rockies, are the oldest and the 

 most permanent of the earth's formations ; and 

 the " steadfast mountains/' the " everlasting 

 hills," the " eternal Alps," are the common fig- 

 ures of speech used about them. But the 

 lofty mountain would seem the youngest of the 

 earth's formations, and so far from being " eter- 

 nal "or " everlasting," it is wearing away much 

 faster than the lower heights. For the mountain 

 is an exposed point of land a high point and 

 is always suffering from the wear of the ele- 

 ments. Of these elements, water is the most de- 

 structive of all. The snow-cap of the peak is a 

 condenser and a cloud-maker for the vapors of 

 the plains. It rains or snows on the upper ridges 

 night after night when never a drop or flake falls 

 in the valley. The water collects in swift-run- 

 ning streams, the more destructive for their ve- 

 locity, that cut and rib the mountain-side. The 

 soft portions of earth and rock are eaten out first, 

 and the hard parts crumble from lack of sup- 

 port. Then the sun-heat expands, the cold con- 

 tracts and splits, the winds and rains erode, the 



The age of 

 mountaint. 



Agents of 

 denudation. 



