246 FIRST YEAR COURSE IN GENERAL SCIENCE 



tool held in a firm grasp, scraping and chiseling the rock 

 beneath. Erosion takes place in the bed of the glacier and 

 along the sides of the valley. Rocks and earth, brought 

 by avalanches to the surface of the glacier, are carried 

 along by the moving ice. As the lower end of the glacier 

 is always melting in the warm season, the rubbish lying on 



FIG. 130. SNOW FIELD AND GLACIER 



This glacier comes from the high Alps. The mountains are so steep 

 that snow cannot rest upon their peaks. 1. How are the snow fields formed? 

 2. How do you account for the roughness of the surface of the glacier? 



the surface and embedded in the ice falls at the end of the 

 glacier. The material deposited in a ridge at the end is 

 known as the terminal moraine. 



266. The Retreat of a Glacier. Where a distinct ridge 

 of mixed coarse and fine rock, sand, and clay is found across 

 an old valley or stretching over a continent, it indicates the 



