92 



Sierra Club Bulletin. 



The mean of our pressure-readings on the summit was 

 17.690 inches, while the mean of the Langley readings 

 was 17.588 inches. There are only four of the series by 

 Langley which were taken at hours comparable with ours, 

 — namely, September 4, 8:30 a.m. ; September 5, 12:40 

 P.M.; September 6, 8:17 a.m.; and September 6, 9 a.m. 

 The mean of these corrected and reduced is 17.609 inches. 

 The difference, therefore, is but 0.081 of an inch. The 

 temperatures also agree fairly well. 



Professor Langley gives the elevation of Mt. Whitney 

 as 14,522 feet, or 10,762 feet above his base-station at 

 Lone Pine.* 



We found deposited on the summit a record of an 

 ascent made on August 23, 1902, by Professors Kellogg, 

 Hallock, Putnam, and others, in which it is stated that 

 the temperature was then 34° F., and the boiling-point, as 

 determined by William Hallock, 186.4° F. It is interest- 

 ing to note that the pressure corresponding to this boiling- 

 point would be 17.58 inches. 



On October 8, 1895, Hutchings and others ascended 

 the mountain and reported that water boiled at 187° F. 



Wheeler's Determinations. — Wheeler gives as the 

 heightf determined by the adopted mean of barometric 

 observations made by the observers of his survey party 

 of 1875, 14,471 feet. The mean of three readings, at 

 half-hour intervals, on September 24, 1875, after being 

 corrected and reduced, was 17.796 inches; temperature, 

 35-3° ; wet-bulb reading, 29.0°. A similar mean for 

 October 13, 1875, was 17.840 inches; temperature, 36.7°; 



* The exact elevation of the station at Lone Pine is uncertain, 

 t" United States Geological Surveys West of the One Hundredth Meridian." 

 Wheeler, 1889, p. 95. 



