1878.] On the Function of Respiration at Various Altitudes. 293 



II. 14 Summary of an Experimental Inquiry into the Function of 

 Respiration at Various Altitudes." By William Marcet, 

 M.D., F.R.S. Received March 19, 1878. 



These experiments were mainly undertaken with the view of in- 

 quiring into the state of the respiration of tourists at various altitudes, 

 and under the different circumstances met with on Alpine excursions. 

 I was engaged with the present work in the last three summers ; the 

 stations selected being : — 



1. A village named Yvoire near the Lake of Greneva, altitude 1,230 

 feet. 



2. The Hospice of the Great St. Bernard, 8,115 feet. 



3. The Riffel Hotel, Zermatt, 8,428 feet. 



4. The St. Theodule Hut, 10,899 feet. 



5. The summit of the Breithorn, 13,685 feet. 



An interesting paper on the physiological influence of the fall of 

 atmospheric pressure by A. Mermod appeared in " The Bulletin de la 

 Societe Vaudoise des Sciences Naturelles " for September, 1877. After 

 making a series of observations on the pulse, rate of breathing and 

 temperature of the body at several, though but moderate altitudes, he 

 selects Strasburg, 124 metres, and a place called Ste. Croix, 1,100 

 metres, for his experiments on respiration. He made 35 experiments 

 at Strasburg, and 32 at Ste. Croix, the temperature of the air being 

 much the same at both places while occupied with the inquiry. He 

 states, in conclusion, that the absolute and relative quantity of carbonic 

 acid exhaled from the lungs increases by a change of residence to 

 higher altitudes, while the rate of respiration (frequence re&piraioire) 

 remains always the same, and there is a diminution in the weight of 

 the air breathed. 



My results are similar to those obtained by Mr. Mermod, the only 

 point on which we may differ referring to the rate of breathing. My 

 case, however, is slightly different from that of the former experi- 

 mentalist ; he resided two or three months at his stations, while, with 

 the exception of Yvoire, where I spend two or three months every 

 summer, I merely remained at mine long enough to make my experi- 

 ments. I ascended the Breithorn with my instruments on three 

 different occasions ; the second time my stay on the summit lasted five 

 hours fifty-one minutes, and the third time also between five and six 

 hours. I was engaged with the experiments at the St. Theodule Pass 

 during eight days in succession in 1875, and returned there last 

 summer for three days to complete the inquiry, one of those days 

 being taken up with the ascent of the Breithorn with my instruments. 

 The inquiry was carried on for three days at the St. Bernard, and for 

 the same lteigth of time at the Riff el. 



