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Sierra Club Bulletin 



it so happens, has just recently been beheaded by the United 

 States Coast and Geodetic Survey, and now can claim no more than 

 14,162 feet, that is, 218 feet less than it once boasted. The great volcano 

 of Puget Sound is thus left well in the lead. 



A review of the different figures that have been announced in the 

 past for each of the higher peaks of the United States would almost 

 justify one to infer that these summits have a peculiar habit of fluctu- 

 ating in height from time to time. Both Rainier and Shasta have been 

 notorious for their inconstancy; so much so indeed that it is to be 

 feared that the public will lose faith in the trustworthiness of altitude 

 determinations in general. There is good reason to beHeve, however, 

 that the last announcements for these two peaks are not likely to be 

 changed again. About Mt. Shasta, perhaps the Coast Survey is the 

 only party able to speak positively; but as regards Mt. Rainier, the 

 Geological Survey feels satisfied that the new figure is the best that 

 can be obtained with modern methods and instruments. 



The elevation of Mt. Whitney (14,501 ft.), it may be remembered, 

 was determined by actual leveling, but such procedure would have been 

 impossible on Mt. Rainier, as the most practicable route to its sum- 

 mit leads over many miles of snow and ice, and up a precipitous chute 

 several hundred feet in height. On thawing snow accurate leveling is 

 out of the question, for the instrument cannot be set up so firmly that it 

 will not settle slightly between back and fore sights. To execute this 

 pottering kind of work in freezing weather would entail both hardship 

 and great expense. But the obstacle that would have proved entirely 

 insuperable to levels on Mt. Rainier and led to the abandoning of 

 that method is the dreaded Gibraltar Rock, well known to many who 

 read this magazine. To carry levels up its precipitous side is for 

 practical considerations all but impossible. 



It was necessary, in the case of Mt. Rainier, to resort to long-dis- 

 tance methods of angulation. That is to say, sights were taken to its 

 summit from neighboring peaks, six to eight miles distant, the altitudes 

 of which had been carefully determined, and the positions of which 

 with respect to the mountain's summit had been computed from a 

 scheme of triangulation. 



It is not possible to execute vertical-angle measurements of this sort 

 with the precision obtainable by leveling; at the same time, by provid- 

 ing a sufficient number of checks and repeating each measurement many 

 times, a result can be attained that can be reHed on within a foot or 

 two. And closer than that, the determination of a snow-capped peak, 

 such as Mt. Rainier, need scarcely be; for its actual height is bound 

 to fluctuate by several feet from year to year and even from month to 

 month. 



It is gratifying to note how closely the new trigonometric determina- 

 tion of Mt. Rainier accords with the barometric one of Prof. Alex- 

 ander McAdie (14,394 ft). It is hoped that this agreement between 

 the results of two fundamentally different methods will strengthen 



