THE GLACIEK LAKES 109 



of these mountain lakes may be made from data 

 already suggested, but I cannot stop here to present 

 the subject in detail. I must also forego, in the 

 mean time, the pleasure of a full discussion of the 

 interesting question of lake-basin formation, for 

 which fine, clear, demonstrative material abounds 

 in these mountains. In addition to what has been 

 already given on the subject, I will only make this 

 one statement. Every lake in the Sierra is a glacier 

 lake. Their basins were not merely remodeled and 

 scoured out by this mighty agent, but in the first 

 place were eroded from the solid. 



I must now make haste to give some nearer views 

 of representative specimens lying at different eleva 

 tions on the main lake-belt, confining myself to des 

 criptions of the features most characteristic of each. 



SHADOW LAKE 



THIS is a fine specimen of the oldest and lowest 

 of the existing lakes. It lies about eight miles above 

 Yosemite Valley, on the main branch of the Merced, 

 at an elevation of about 7350 feet above the sea ; and 

 is everywhere so securely cliff-bound that without 

 artificial trails only wild animals can get down to 

 its rocky shores from any direction. Its original 

 length was about a mile and a half ; now it is only 

 half a mile in length by about a fourth of a mile 

 in width, and over the lowest portion of the basin 

 ninety-eight feet deep. Its crystal waters are clasped 

 around on the north and south by majestic granite 

 walls sculptured in true Yosemitic style into domes, 



