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Sierra Club Bulletin. 



ried to the summit by McAdie and Le Conte with other 

 instruments on July 8, 1903.* 



In July, 1 88 1, Professor Langley's party went into 

 camp near what is now known as Langley's Lakes. The 

 expedition entered the region by way of Lone Pine, cross- 

 ing the divide south of the summit and camping at an 

 elevation of approximately 12,000 feet. The importance 

 of the observations then made has not been fully under- 

 stood nor appreciated even by scientific workers. To the 

 people at large comparatively little has been made known. 

 In the coming years, as the various problems of solar and 

 stellar atmospheres press for solution, a truer appreciation 

 of Langley's high-order work in connection with the solar 

 constant and the absorption of energy by the earth's 

 atmosphere will be had. Not the least in his long line of 

 honors, it seems to me, is the credit due him for farsight- 

 edness and sagacity in selecting the site, suitable for work, 

 and the attempt to demonstrate the truth of his belief. 



Of the last scientific expedition to the summit, the 

 Campbell-Abbot party of August-September, 1909, more 

 will be said further on in this paper ; but it is of more than 

 passing significance that from the vantage ground of 

 Whitney should come the first authoritative knowledge 

 of the probable amount of water vapor and oxygen in the 

 atmosphere of our neighboring planet. Mars. 



So far as the writer knows the first men to spend a 

 night on the summit of Mount Whitney were Michaelis, 

 Nanry and Keeler, of Professor Langley's party.f Ob- 

 servations of temperature and vapor pressure were made 

 at intervals September 2d to 5th, 1881. Twenty-eight 

 years afterwards, August 28th to September 4th, 1909, 

 continuous records were obtained of pressure, humidity 

 and temperature for the entire period by McAdie while a 

 member of the Campbell-Abbot party. 



* Members of the Sierra Club will be interested to know that the height pub- 

 lished in Sierra Club Bulletin as the outcome of this measurement (14,515 

 feet) was within thirteen feet of the true height, determined two years later 

 by precise leveling methods of the United States Geological Survey. 



t John Muir was among the first to climb Mount Whitney and spend a 

 night on the summit. 



