MOUNT RAINIER 



rather, a broadly truncated mass resembling an enor- 

 mous tree stump with spreading base and irregularly 

 broken top. Its life history has been a varied one. 

 Like all volcanoes, Rainier has built up its cone with 

 the material ejected by its own eruptions with 

 cinders and bombs (steam-shredded particles and 

 lumps of lava), and with occasional flows of liquid 

 lava that have solidified into layers of hard, basaltic 

 rock. At one time it attained an altitude of not less 

 than 16,000 feet, if one may judge by the steep in- 

 clination of the lava and cinder layers visible in its 

 flanks. Then a great explosion followed that destroyed 

 the top part of the mountain, and reduced its height 

 by some 2,000 feet. The volcano was left beheaded, 

 and with a capacious hollow crater, surrounded by 

 a jagged rim. 



Later on this great cavity, which measured nearly 

 3 miles across, from south to north, was filled by two 

 small cinder cones. Successive feeble eruptions added 

 to their height until at last they formed together a 

 low, rounded dome the eminence that now consti- 

 tutes the mountain's summit. It rises only about 

 400 feet above the rim of the old crater, and is an in- 

 conspicuous feature, not readily identifiable from all 

 sides as the highest point. In fact, so broad is the 

 mountain's crown that from no point at its base can 

 one see the top. The higher portions of the old crater 

 rim, moreover, rise to elevations within a few hundred 

 feet of the summit, and, especially when viewed from 

 below, stand out boldly as separate peaks that mask 

 and seem to overshadow the central dome. Espe- 

 cially prominent are Peak Success (14,150 feet) on the 

 southwest side, and Liberty Cap (14,112 feet) on the 

 northwest side. 



The altitude of the main summit has for many years 

 been in doubt. Several figures have been announced 

 from time to time, no two of them in agreement with 

 each other ; but all of these, it is to be observed, were 



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