vi MOUNTAINS 227 



and since their elevation have probably 

 always stood, above the range of ice, and 

 hence their bold peaks. In Scotland, on 

 the contrary, and still more in Norway, the 

 sheet of ice which once, as is the case with 

 Greenland now, spread over the whole coun- 

 try, has shorn off the summits and reduced 

 them almost to gigantic bosses ; while in 

 Wales the same causes, together with the 

 resistless action of time for, as already 

 mentioned, the Welsh hills are far older 

 than the mountains of Switzerland has 

 ground down the once lofty summits and 

 reduced them to mere stumps, such as, if 

 the present forces are left to work out their 

 results, the Swiss mountains will be thou- 

 sands, or rather tens of thousands, of years 

 hence. 



The " snow line " in Switzerland is gener- 

 ally given as being between 8500 and 9000 

 feet. Above this level the snow or neve 

 gradually accumulates until it forms " glac- 

 iers," solid rivers of ice which descend more 

 or less far down the valleys. No one who 

 has not seen a glacier can possibly realise 



