GLACIERS 207 
and irresistible force, until its enemy, the sun, trans- 
forms it to water, when it courses rapidly down the 
mountain valleys m torrential streams. 
Work of the Glacier. ‘The ice sheet is a great agent 
of transportation. It differs from the river in this 
respect, —that being a solid, it will bear along large 
and small fragments side by side, even though its 
Fia,. 111. 
End of a Swiss glacier, showing terminal moraine. 
rate of motion is very slow. Hence the deposits 
made by the glacier bear no relation to its velocity, 
being compounded of fragments of all sizes, thrown 
together where the ice left them. 
Another difference between rivers and glaciers is 
found in the work of erosion which they do. The 
river bears along sediment, buoying it up and lessen- 
ing its weight, but hurling it against the river bed; 
