GLACIERS 



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worn, since they are carried bodily and not rolled as in 

 streams. 



On the under surface of, the glacier, rocks are dragged 

 along firmly frozen into the ice. The weight of the gla- 

 cier above presses them with tremendous force upon the sur- 

 face over which the glacier passes. In this way scratches 

 or grooves are made in the bed rock underlying the gla- 

 cier, as well as upon the bowlders themselves. Scratches 



A STONE SCRATCHED BY A GLACIER 



of this kind are called glacial scratches. The rubbing of 

 the rocks upon each other wears them away and grinds 

 them into fine powder called glacial flour, which gives a 

 milky color to the streams flowing from glaciers. 



If a glacier extends over a region where the surface has 

 been weathered into soil, this fine material may be shoved 

 along under the ice for great distances. 



Wherever glaciers are easily approached they form a 

 great attraction for the summer tourist. The glistening 

 white snow fields circled by the green foliage of the lower 



