INFLUENCE OF EXTREME HEAT AND COLD. 
8i5 
extreme heat upon animals. Provoost and Fahrenheit, working under 
the direction of Boerhaave, 1 found that a dog and a cat placed in a hot 
stove (03°) died in twenty-eight minutes, whilst a sparrow, under 
similar conditions, died in seven minutes. Duntze 2 observed that 
dogs could live in an atmosphere at 42° "2, but died when the 
temperature was raised to 45°. It was found by Delaroche 3 that 
cats, rabbits, pigeons, and various insects could remain for one 
hour in a temperature of 36° without fatal results ; the most marked 
symptom was the greatly quickened respiration. When the tempera- 
ture was raised to 45° or 53°, the cat and rabbit died within two hours, 
the pigeon in one hour and twenty minutes, the most marked symptom 
being convulsions. A frog, under similar conditions, was alive at the 
end of two hours. The temperature of a rabbit exposed to a heat of 45° 
for one hour and forty minutes rose from 39° '7 to 43° - 8. Exposure to 
moist heat quickly raised the temperature of animals, as shown in the 
following; table : — 
Animal. 
Temperature 
before. 
Temperature 
after. 
Moist Heat. 
Time of 
Exposure. 
Rabbit .... 
Guinea-pig . 
Pigeon .... 
Frog .... 
39°-6 
38°-4 
41°'8 
Not stated 
43° 
44°-2 
46°-9 
26° 
27 = -8 
38°-7 
40° -7 
41°-9 
25° -6 
27°-2 
55 minutes 
55 
42 
73 
50 
The effect of dry and moist hot air upon different animals was 
determined by Bernard 4 in numerous experiments ; some of the results 
are here given : — 
Animal. 
Dry Air. 
Death 
Animal. 
Dry Air. 
Death. 
Pigeon 
90° 
In 6 min 
utes Rabbit . 
100' 
In 10 minutes 
90° 
6i , 
. 
so 3 
18 ,, 
Dog 
90° 
24 , 
. 
80° 
17 „ 
Guinea-pig 
100° 
5 , 
>! 
65° 
25 ,, 
100° 
6 . 
Dog 
100° 
18 „ 
Rabbit . 
100° 
10 , 
I! 
90° 
24 „ 
Dog 
100° 
18 , 
. 
80° 
30 ,, 
Rabbit . 
100° 
7 , 
In moist hot air the animals died very quickly ; thus, when the 
temperature was 80°, 60°, and 45°, the rabbits died in two, three, and 
ten minutes respectively. Experiments made by immersing the body 
of the animal in hot water gave similar results. To determine the effect 
of exposing the body to dry heat without warming the air used for 
respiration, Bernard made the following comparative experiments upon 
rabbits of similar size : — 
1 "Praelect. Anat.," p. 211 ; "Elem. de chymie," tome i. pp. 148, 277, 278. 
2 Quoted from Delaroche ( 3 ). 
s Journ. dephi/s., Paris, 1806, tome lxiii. pp. 207, 468 ; 1810, tome lxxi. p. 289. 
* Gaz. mid. de, Paris, 1859, tome xiv. p. 462; " Lecons sur la chaleur animale," 
1876, p. 349. 
