THE WORK OF SNOW AND ICE 263 



The topography favoring deposition is much the same as that 

 favoring erosion, but the two processes are not favored at the same 

 points.' Erosion is greatest on the "stoss" side (the side against 

 which the ice advances) of an obstruction, and deposition on the 



Fig. 217. Crag and tail. The passage of glacier ice is likely to leave a con- 

 siderable body of drift in the lee of the boss of rock, C. 



lee side (Fig. 217). The ice is likely to be overloaded (1) just be- 

 yond a place where conditions have favored the gathering of a 

 heavy load, and (2) where the ice is rapidly thinning. On the 



Fig. 218. Glacier building an embankment. Southeast side of McCormick 

 Bay, North Greenland. 



whole, the deposition of material beneath the main body of a glacier 

 is much more than balanced by erosion in the same position. 



2. At and near the end of a glacier, deposition goes on faster 

 than elsewhere, chiefly because of the rapid melting, and therefore 

 the thinning and weakening of the ice. If the end of the glacier 

 is stationary in position, drift is being continually brought to it 



