central channel. 



This is the expression of the reduction of the lateral factor 

 of glacial strength. Then the ice will tend to cut narrower 

 and steeper cirques and valleys along the floors of the old 

 ones. (Fig. 1G.) 



Fig. 16. 



■ i ! A ■' 2LA1 ' 



ey, Yoseniite Region. A smaller glacial valley i 

 tvated in the floor of an older glaciation. The rei 

 der floor is partly covered with morainic materia 



