1922] EDWARDS, GEOLOGICAL WORK AT RAINER NATIONAL PARK 53 



naiits of the old crater stand out with conspicuous boldness forming 

 peaks as seen from below, and have received separate names. Among 

 these may be mentioned Success Peak, on the western slope of the 

 mountain. It marks the point where, it is said, the first successful 

 party climbed the volcano. 



The actual altitude of the mountain was in doubt for many years 

 and figures were announced from time to time — no two of which were 

 in agreement. In 1913, however, the United States Geological Survey 

 made an accurate measurement of the altitude which was determined 

 to be 14,408 feet above sea level. This figure makes Mt. Rainier the 

 third highest mountain in the United States. The probability of error 

 in this determination is not greater than one or two feet, and is, if any- 

 thing, more exact than the summit itself, for the highest point on the 

 mountain is a drifting snow-bank which varies in altitude from year 

 to year. This snow-mound at the summit was once supposed to be the 

 highest point in the United States, and for that reason was given the 

 name of Columbia Crest. It is the only permanent snow-mass on the 

 summit of the mountain. Enough remains of the internal heat of the 

 volcano to melt the snow in the craters themselves throughout the 

 greater part of the year. In the eastern crater, indeed, steam still rises 

 from below and melts out caverns in the snow-cap which afford shelter 

 to parties if forced to remain over night at that altitude. That this 

 volcano should still show some activity is not surprising when one con- 

 siders the recency of its eruptions. Actual records exist of slight erup- 

 tions in 1843, 1854, 1858, and 1870, and Indian legends are said to tell 

 us of still earlier eruptions. 



In spite of the recent activity of the mountain, it appears that it 

 has been snow-clad for a considerable length of time. In fact, the 

 present glaciers are merely remnants of greater ice sheets which in 

 past geologic time covered the slopes and base of the mountain. The 

 original material .of which the mountain was made has, in many places, 

 suffered great erosion and large cjuantities have been carried away by 

 the ice streams. This action has gouged out a number of long tongue- 

 like valleys on the sides of the mountain, many of which reach far into 

 the core of the mass and show us a section of the material of which 

 the volcano is composed. At several places along the slopes of the 

 mountain, isolated crests and ridges remain between these glacial val- 

 leys. A few of them, like Little Tahoma on the east side, stand out 

 very prominently, and in any other situation would be considered con- 

 spicuous peaks. Near the summit of the mountain, similar small rocky 



