(TUounfain Bd^tB 



makers of lake-basins, large and small. These 

 basins were formed in darkness, and hundreds 

 and even thousands of years may have been 

 required for the ice to carve and set the gems 

 whose presence now adds so much to the light 

 and beauty of the rugged mountain-ranges. The 

 ponderous glaciers or ice rivers in descending 

 from the mountain-summits came down steep 

 slopes or precipitous walls and bore irresistibly 

 against the bottom. The vast weight of these 

 embankments of ice moving almost end-on, 

 mixed with boulders, tore and wore excava- 

 tions into the solid rock at the bottom of each 

 high, steep descent. 



Nature's ways are interestingly complicated. 

 Both the number and the location of many of 

 these glacier lakes are due in part to the pre- 

 vailing direction of the wind during the last 

 glacial epoch. This is especially true of those 

 in the Snowy Range of the Rocky Mountains, 

 which fronts the Great Plains. The majority 

 of the lakes in this range are situated on its 

 eastern slope. Westerly winds undoubtedly 

 prevailed on these mountains during the de- 



151 



