474 



Intelligence and Miscellaneous Articles* 



guides, feels a heaviness of the head and a somnolence which are 

 frequently very painful, evidently due to a venous stagnation and 

 imperfect oxygenation of the blood. Even after two hours' com- 

 plete rest and while still fasting, the pulse always remains between 

 90 and 108. The sphygmograph applied to the wrist after an hour's 

 rest indicates an extremely feeble tension, and a most pronounced 

 dicrotism. According to M. Marey, this defect of tension must be 

 due to the fact that, owing to muscular motion, the blood flows more 

 rapidly through the small vessels. When the sphygmograph is ap- 

 plied to persons suffering from mountain-sickness, curves are ob- 

 tained which exactly resemble those obtained in cases of algidity. 

 The pulse is so weak that the spring of the instrument is scarcely 

 raised. This alone would indicate a general cooling of the body. 



Internal Temperature of the Body. — This w r as always taken with 

 great care at different heights, the thermometer being placed in the 

 mouth underneath the tongue ; the mouth itself vvas closed, and 

 breathing was effected through the nose. The thermometer was a 

 Walferdin's maximum with index, on which, from 30° to 40°, the hun- 

 dredths of a degree could be read off. The index facilitated the 

 reading, and prevented any errors. The instrument was always left 

 for at least fifteen minutes in the mouth, a time which was far more 

 than sufficient for it to reach the maximum. 



While fasting and exactly in the same conditions, during the ascent , 

 the decrease of the internal temperature of the body is very remark- 

 able, and is proportional to the altitude reached. This is easily seen 

 by an inspection of the following Table, which condenses the ob- 

 servations made upon myself during my two ascents of Mont Blanc. 



Temperature taken under the Tongue. 



Names of the stations. 



Height 

 in feet. 



Ascent on 

 Aug. 17, 1869. 



Ascent on 

 Aug. 26, 1869. 



Temperature 

 of the air. 



At rest. 



In mo- 

 tion. 



At rest. 



In mo- 

 tion. 



Aug. 

 17. 



Aug. 

 26. 





656 



3,444 



4,920 



5,264 



6,721 



10,002 



12,897 



14,944 



15,777 



36°4 

 36-5 

 36-4 

 36-6 

 36-5 

 86-5 

 36.3 

 36-4 

 36-3 



o 



36-2 

 36-3 

 35-7 

 34-8 

 33*3 

 33- 1 

 32-8 

 32-2 

 320 



o 



S70 



36-3 

 36-3 

 36-4 

 36-3 

 36-7 

 35-7 

 36 6 



o 



'353 



34-3 

 34-2 

 33-4 

 33-3 

 32-5 

 32-3 

 31-8 



+227 

 + 101 

 + 11-2 

 + 11-8 

 + 13-2 



- 0-3 



- 8-2 

 -10-3 



- 91 



+ 12-4 

 + 134 

 + 136 

 + 141 



- 1-5 



- 6-4 



- 42 



- 3 4 



Chamounix 



Cascade-du-Dard 



Chalet-de-la-Para 





Granris-Mulets 



Grand-Plateau 



Bosses-du-Dromadaire ... 

 Top of Mont Blanc 



It is thus seen that, during the muscular efforts of the ascent, the 

 internal temperature of the body may be lowered in ascending from 

 3444 to 15,777 feet by from 4° to 6° — an enormous diminution for 

 mammals. If we remain stationary for a few seconds, the tempera- 

 ture rapidly rises to very nearly its normal maximum ; at the top of 



