218 



NATURE FOR ITS OWN SAKE 



The ap- 

 proaches to 

 mountains. 



Seen from a, 



distance. 



rises abruptly from the surrounding country. 

 The fold has usually left its mark for hundreds 

 of miles on either side of the chain, and the 

 ascent to the topmost peaks is made by a 

 gradual rise from the plains to the table-lands, 

 and from these to the foot-hills, so that fre- 

 quently the mountain-climber finds himself 

 thousands of feet above sea-level before the 

 outlines of the ridge appear at all. This is not, 

 of course, true of the Alps, where the deep 

 valleys enable one to come to the base of Mt. 

 Blanc, for instance, and see the mountain itself 

 towering twelve thousand feet higher up ; but 

 it is quite true of the Kocky Mountains, espe- 

 cially in the Montana region. The ascent is 

 gradual from the prairie " divides/' which one 

 thinks of (erroneously, no doubt) as the little 

 wrinkles of the earth's surface, through table- 

 lands and foot-hills covered with vegetation and 

 cut by beautiful valleys. The hills near at 

 hand are bright green, but they grow bluer and 

 the valley shadows paler as they recede from us, 

 and oftentimes in clear weather one can see far 

 away, beyond the timber-crowned slopes of the 

 foot-hills, the faint gray silhouette of the high 

 mountain-ridge, almost lost in the blue of the sky. 

 The fold of the earth crust is usually a long one. 



