118 



PHYSIOGRAPHY 



The effect of ice-sheets on valleys is not so striking. Great ice- 

 sheets override hills and divides as well as valleys. The hills over- 







Fig. 121. Diagram representing a hill unworn by ice, and the irregular con- 

 tact of soil and rock. 



Fig. 122. Diagram showing the effect of glacial wear on a hill such as is 

 shown in Fig. 121. 



ridden are worn down and smoothed off (Figs. 122 and 123), and 

 the wear is greatest on the side of the hill against which the ice 

 moves (Fig 122). 



Fig. 123. A hill smoothed by the glacier ice which overrode it. Shore of 

 North Greenland. (From photo, by Chamberlin.) 



