442 
DR. DAVY ON THE TEMPERATURE OF MAN WITHIN THE TROPICS. 
Tongue. 
Pulse. 
Respira- 
tions. 
Air of 
room. 
March 7, 1847) h** 15"* a.m. Just risen 
March 7) 1847, 3 p.M. During the last two hours taking gentle exercise 
9?8 
52 
14 
o 
74 
within doors, making some chemical experiments 
98-3 
56 
15 
82 
August 17, 1847, 5^ 45*" a.m. Just risen 
August 17, 1847, 7** 45*** A.M. During last half hour walking slowly in 
shaded gallery, exposed to the wind ; feelings agreeable; feet and hands 
97*8 
62 
15 
77 
warm 
97*8 
68 
16 
80 
August 19 , 1847,5** 45*** a.m. Just risen 
August 19, 1847, 8 A.M. Last half hour walking in gallery; not exposed lo 
98-6 
62 
15 
79 
the wind; perspiring gently 
98-4 
70 
17 
81 
August 21, 1847, 5** 35*** a.m. Just risen 
August 21, 1847, 7^ 30*** A.M. After walking about half an hour; hands 
98-4 
60 
15 
78 
and feet glowingly warm 
98-2 
76 
17 
81 
August 22, 1847, 5** 45*** a.m. Just risen 
August 22, 1847, 7^ 45*** A.M. After walking in gallery about half an hour. 
98-5 
62 
16 
79 
very lightly clad, exposed to the wind ; hands and feet very warm 
98-2 
78 
17 
82 
To appreciate the effect of gentle exercise on the temperature, it requires to be 
mentioned and kept in mind, that had not such exercise been taken, the thermometer 
would have risen on its second application from '3° to ‘5° higher than at the first. 
The feeling of increased warmth in the hands and feet from gentle exercise has 
been noticed in three instances. The diffusion of heat to the extremities, owing no 
doubt to a freer circulation of the warming medium — the blood — may partly account 
for the cooling effect under the tongue, and probably in the deep-seated parts from 
the exercise under consideration. The high temperature commonly observed in the 
extremities within the tropics, is a circumstance very deserving of note. In the daily 
observations appended, a record is given of the temperature of the hand during two 
months, noticed three times a day ; from which it appears that on an average it was 
less than that under the tongue by only 1°. For the purpose of ascertaining the heat 
of the hand, the bulb of the thermometer was placed between the middle of the palm 
and the ball of the thumb, and so covered was gently pressed. 
6, Of the Effect of Change of the Temperature of the Atmosphere on the Temperature. 
In illustration of this effect, I shall notice only a very few of the observations ob- 
tained in the West Indies, corroborative of those collected many years ago in the 
island of Ceylon. 
The situation of Villa Nova has already been mentioned : it was there that most of 
them were made, that spot being well-fitted for trials of the kind, the temperature 
there by day rarely exceeding 80°, even at the hottest time, and always below 80° at 
night, often requiring the closure of the bed-room windows, and occasionally a 
blanket in addition to the bed-clothes. 
