MOUNT RAINIER 



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 in- 

 superable to levels on Mount Rainier and led to the 

 abandoning of that method is the dreaded Gibraltar 

 Rock, well known to many who read this magazine 

 [Sierra Club Bulletin]. To carry levels up its precipi- 

 tous side is for practical considerations all but im- 

 possible. 



It was necessary, in the case of Mount Rainier, to 

 resort to long-distance methods of angulation. That is 

 to say, sights were taken to its summit from neighbor- 

 ing peaks, six to eight miles distant, the altitudes of 

 which had been carefully determined, and the posi- 

 tions 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 measure- 

 ments of this sort with the precision obtainable by 

 leveling ; at the same time by providing a sufficient 

 number of checks and repeating each measurement 

 many times a result can be attained that can be relied 

 on within a foot or two. And closer than that the 

 determination of a snowcapped peak, such as Mount 

 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 trigo- 

 nometric determination of Mount Rainier accords 

 with the barometric one of Prof. Alexander McAdie 

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

 the results of two fundamentally different methods 

 will strengthen public faith in their reliability, and lead 

 to the discarding of other figures (some of them much 

 exaggerated) that have appeared in print from time to 

 time. 



In closing, it may be said, that the Geological Sur- 

 vey's bulletin little more than hints at the fortitude 



300 



