MOUNTAINS 



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scarcely 2000 feet above sea level, but they are called mountains 

 because they rise from a low plain. Some elevations in the 

 Rocky Mountains are 3000 feet high, but they are called hills 

 because they do not rise conspicuously above the rugged country 

 which surrounds them. 



In addition to the mountains which are scattered over the 

 country there are broad wide elevations called plateaus. The 



FIG. 273. The tops of mountains are generally small in area. 



Colorado Canon Plateau is one of the most famous plateaus in 

 the world (Fig. 272). A plateau is an elevation which has a 

 large area on its summit ; a mountain is an elevation which has 

 a small area on its summit (Fig. 273). The expression "moun- 

 tain peak " comes from the fact that the top of the mountain 

 is peaked or sharper than its base. Plateaus, like mountains, 

 vary greatly in elevation ; some, like the Piedmont Plateau east 

 of the Appalachian Mountains, are only a few hundred feet 

 higher than the plain beneath them; others, like the Great 



