450 Experimenis on the Influence of the Brain 
Half an hour after the rabbit was killed, the heat in the 
rectum was 99°. ‘ 
At 45 minutes it had fallen to 98°. 
At the end of an hour the heat in the rectum was 96%. 
At an hour and a quarter it was 95°. 
4#.t an hour and a half it was 94°. 
At an hour and forty minutes the heat in the rectum was 
93°, and in the bag of the pericardium g02.- 
~The following table will show the comparative tempera- 
ture of the two animals at corresponding periods. 
Rabbits with artificial | 
; Dead Rabbit. 
respiration. 
ia: Therm. in thel Therm. in the ‘Therm. in the! Pherm. in the 
Rectum. Pericardium.| Rectum. Pericardium. 
Before the 
Expesnieelle 1005 1005, 
30 min. 07 99 
45 — 952 1 98 
60 — 94 964 
75 — 92 95 
90 — 9] 94 
100 — got 874 93 907 
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 arti- 
ficial respiration, cooled more rapidly than the dead rabbit, 
but the difference was more perceptible in the thorax than 
m 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 Jungs were inflated, must 
necessarily have abstracted a certain quantity of heat, par- 
ucularly as its influence was communicated to all parts of 
the body, in consequence of the continuance of respiration, 
It was suggested that some animahsheat might have been 
generated, though so small in quantity as not to counter- 
balance the cooling powers of the air thrown into the lungs. 
It is difficult, or impossible, to ascertain with perfect accu- 
racy, what effect cold air thrown into the lungs would have 
on the-temperature of an animal under the circumstances-of 
‘the last experiment, independently of any chemical action 
on the blood; since, if no chemical changes were ro 
: the 
