The Mighty Deep 



But why not rivers of snow, if a glacier 

 means the draining away of snowfields ? 



Well, so they are — rivers of snow. But the 

 heavy weight of overlying snow above, and the 

 great pressure of descending masses later, welds 

 the light and delicate snow into hard ice. Those 

 tiny needles, of which the falling snow was made, 

 are crushed closer and closer, till they form a 

 solid block, which loses all resemblance to snow. 

 In summer the melting of the surface by day, 

 and its freezing again by night, help forward this 

 transformation. 



Thus a glacier is literally an Ice- River, a huge 

 long tongue of ice, squeezed from beneath snow- 

 fields, and creeping down a valley. 



Such rivers vary much in size. Some of the 

 Swiss glaciers are between twenty and thirty 

 miles long, in parts two or three miles wide, and 

 often hundreds of feet deep. Starting above the 

 snow-line they sometimes reach thousands of feet 

 below it, the milder air falling to end their exist- 

 ence sooner. So enormous are the ice-masses, 

 that not all the strenorth of the summer sun can 

 make away with them. Of course, each square 

 yard in turn does melt, and does help to feed 

 the river of water which rushes away from the 



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