MOUNT RAINIER 



In the truncated summit of Mount Rainier there are 

 three craters. The largest one, partially filled by the 

 building of the two others, is the oldest, and has suf- 

 fered so greatly from subsequent volcanic explosions 

 and erosion that no more than its general outline can 

 be traced. Peak Success and Liberty Cap are promi- 

 nent points on the rim of what remains of this huge 

 crater. Its diameter, as nearly as can be judged, is 

 about 2-J miles. Within the great crater, in the for- 

 mation of which the mountain was truncated and, as 

 previously stated, lost fully 2,000 feet of its summit, 

 there are two much smaller and much more recent 

 craters. The larger of these, the one in which we took 

 refuge, is about 300 yards in diameter, and the second, 

 which is an incomplete circle, its rim having been 

 broken by the formation of its more recent compan- 

 ion, is perhaps 200 yards across. The rim of each now 

 partially snow-filled bowl is well defined, and rises 

 steeply from within to a sharp crest. The character 

 of the inner slopes shows that much rocky material 

 has been detached and has fallen into the cavities 

 from which it was ejected. The rock in the crater 

 walls is in fragments and masses, some of them well 

 rounded and probably of the nature of volcanic bombs. 

 In each of the smaller craters there are numerous 

 steam jets. These show that the rock below is still 

 hot, and that water percolating downward is changed 

 to steam. These steam jets evidently indicate the 

 presence of residual heat and not an actual connec- 

 tion with a volcanic center deep below the surface. 

 All the evidence available tends to show that Rainier 

 is an extinct volcano. It belongs, however, to the 

 explosive type of volcanoes, of which Vesuvius is the 

 best-known example, and there is no assurance that 

 its energies may not be reawakened. 



In descending we chose the south side of the moun- 

 tain, knowing from the reports of many excursionists 

 who had ascended the peak from that direction that 



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