3 g ELEMENTARY SCIENCE 



effects which it produced remain to this day. The ridges 

 and sheets of rock and soil the ice laid down are with us 

 yet. We call the ridges moraines (see Fig. 15), and we 

 call the soil the ice brought down glacial till. It is very 

 fertile. 



Even more conspicuous than the moraines and the till 

 are the effects which the ice produced on the hills and 



FIG. 16. Drawing showing hills of which the rough surfaces 

 have been smoothed off by a glacier. 



valleys they travelled over. As you look over some of the 

 beautiful landscapes of central New York, you can, in the 

 mind's eye, see the great sheet of ice again, as it flowed 

 with tremendous weight down over the rough surface of 

 the land, and then retreated, leaving as evidence of its 

 visit the soft and graceful curves of hill and valley which 

 now delight our eyes (see Fig. 16). It left, too, many 

 lovely lakes. The basins of these it formed by damming 

 up great valleys with the material it dropped. In once 

 firm-bedded rocks you can see the scratches made by 

 material in the ice as it passed over them (see Fig. 17). 



