influence of the Brain on the Action of the Heart, &c. 45 
Half an hour after the rabbit was killed, the heat in the 
rectum was 99 0 . 
At 45 minutes it had fallen to 98°. 
At the end of an hour the heat in the rectum was g 6 
At an hour and a quarter it was 95 0 . 
At an hour and a half it was 94 0 . 
At an hour and forty minutes the heat in the rectum was 
9 3 0 , and in the bag of the pericardium 9 Oj. 
The following table will shew the comparative temperature 
of the two animals at corresponding periods. 
Time. 
Rabbit with artificial respiration. 
Dead Rabbit. vi 
Therm, in the 
Rectum. 
Therm, in the 
Pericardium. 
Thermometer in 
the Rectum. 
Therm, in the 
Pericardium. 
Before the 7 
Experiment j 
ioof 
ioo£ 
30 min. 
97 
99 
45 — 
95 t 
98 
60 — 
94 
9 6 i 
75 — 
9 2 
95 
90 — 
9 1 
94 
100 — 
9°i 
00 
to |"H 
93 
9 oi 
In this experiment, the thorax, even in the dead animal, 
cooled more rapidly than the abdomen. This is to be ex- 
plained by the difference in the bulk of these two parts. The 
rabbit in which the circulation was maintained by artificial 
respiration, cooled more rapidly than the dead rabbit, but the 
difference was more perceptible in the thorax than in the 
rectum. This is what might be expected, if the production of 
animal heat does not depend on respiration, since the cold air 
by which the lungs were inflated, must necessarily have ab- 
stracted a certain quantity of heat, particularly as its influence 
