334 Dr. Marcet on the Temperature of the Human Body at 



2197 metres. When about two-thirds of the way up, I ascertained 

 my temperature under the tongue to be 36°*4. I then got down 

 and ascended on foot as quick as possible to the pavilion ; this 

 lasted 32 minutes, when on nearing my destination I ascertained 

 my temperature to be 35° (after about five minutes' exposure), 

 or 1°*4 lower than when leaving the mule. Shortly before start- 

 ing from Courmayeur, an hour after dinner, the reading of the 

 thermometer in my mouth was 36°*8; at about 650 metres 

 higher up, while ascending on the mule and keeping very quiet 

 all the time, my temperature was 86°'4 ; and after ascending 

 about 328 metres higher up, walking fast, I had lost no less than 

 l°-4 of heat, showing the influence of walking in excess of that 

 which could possibly be due to increased altitude*. 



Taking 36° # 6 as the average temperature at rest, according to 

 my observations we have an average loss of heat of 1 0, 3 due to 

 the act of climbing. 



Result III. — That the temperature of the body, after falling 

 while walking up hill, rises afresh very rapidly on resting, or on 

 merely lessening the speed of ascent. Thus, a few minutes before 

 arriving at the Pavilion du Mont Frety, while in the act of as- 

 cending, the temperature under my tongue was 35°; after half 

 an hour's rest at the pavilion it had risen to 36°*6, or 1°'6. 

 As I was on the point of reaching the Col ( du Geant, while still 

 ascending, the thermometer with its bulb under my tongue 

 showed 34°*5 ; after remaining quiet for eight minutes on the 

 summit of the pass, my temperature had risen to 36 0, 8, or 2°*3. 

 Just before reaching the Chalet des Chablettes, while ascending, 

 temperature after six minutes' exposure 35°*3 ; immediately after 

 recording this in my note-book, although actually without stop- 

 ping, the mercury rose to 36°, and in about five minutes later to 

 36°*4. I had evidently recovered my lost temperature during 

 the interruption of the rate of ascending, owing to the act of 

 taking the note. 



The experiment at Planpraz was equally interesting. Just 

 before arriving, while ascending rapidly and after four minutes' 

 exposure, the temperature was 34°'5, remaining steady for about 

 one minute ; then having lessened my speed, the thermometer rose 

 rapidly to 35°. During the first three minutes' rest at Planpraz 

 the temperature increased again by 0°*8, and after about a quar- 

 ter of an hour was steady at 35°*6. 



I cannot explain the increase of temperature which occurred 

 in the following observations, unless by assuming it to have been 



* This experiment, however, should have been made by riding a mule 

 up to a certain height, ascertaining the body-heat, and repeating the same 

 ascent on foot, when the temperature should have been again determined. 



