418 



LAKE CHELAN 



The bed of Lake Chelan and its principal tributary, Stehekin 

 river, together with the branches of that river, were at one time 

 filled by a vast glacial system, extending from the crest of the 

 Cascades southeastward nearly to Columbia river. The glacier 

 was nearly 100 miles long, and when it was in its prime the ice 

 must have been several thousand feet in thickness. 



MAP OF LAKE CHELAN AND VICINITY, IN THE STATE OF WASHINGTON, 1898 



A glacier is a river of ice, and it behaves almost precisely as a 

 river of water does. Its effects upon its channel are almost pre- 

 cisely similar to those of a river upon its channel, excepting in 

 the fact that all its operations are on a vastly greater scale. The 

 channel of a river may be measured by yards or hundreds of 

 yards, while that of a glacier is measured in miles. The depth 



