560 
ON ANIMAL HEAT. 
actual temperament of newly-born animals is much lower than 
that which they subsequently are possessed of. According to 
the former a new-born infant raised the thermometer no higher 
than 94i°. Something, however, ought to be allowed for evapo- 
ration. Dr. Davy found the temperature of the axilla of a child 
just born to be 98.5° ; twelve hours afterwards it stood at 99°, and 
in three days it was still the same. 
13. In old persons the power of generating heat decreases with 
the decline of vital energy. 
14. Many experimenters have observed a diurnal variation of 
animal temperature. It was seen to be lowest in the morning 
and highest towards evening. According to Anteurieth it is l^° 
Fahr. lower during sleep than in the daytime. 
15. Some have supposed that the process of digestion tended 
to increase the temperature; but from the peculiarly fortunate 
opportunity which Dr. Beaumont had of ascertaining the fact, 
it was found to be but slightly affected by the exercise of that 
function. 
16. Dr. Granville has communicated some remarkable facts 
respecting the temperature acquired by the uterine system during 
parturition. From his statement it appears that the free caloric 
of these organs is then greatly increased. Occasionally he ob- 
served it to rise as high as 120° Fahr. : the elevation always bore 
a proportion to the degree of action excited in the organ. 
17. The external temperature of different parts of the body 
decreases in the ratio of their distance from the centre of circu- 
lation. Thus, a thermometer placed in the axilla of the human 
subject stood at 98° Fahr. ; when placed at the loins it indicated 
a temperature of 96i°, on the thigh 94°, on the leg from 93° to 
91°, and on the sole of the foot it only reached 90°. It was also 
found that the brain possessed a lower temperature than the 
rectum. 
18. Dr. Davy, Magendie, and Thenard, have asserted that 
arterial blood is superior in temperature to venous by 1°. This 
was ascertained by putting a thermometer into the right and left 
sides of the heart. Others have failed to discover this difference ; 
and the late Professor Coleman stated that he had found the right 
side of the heart the warmest by 1° or 2° Fahr. Mayer found 
the temperature of the blood in the jugular vein to be from 2|° 
to 4|° Fahr. lower than that of the carotid, but he could distin- 
guish no difference in the temperature of either side of the heart. 
MM. Becquerel and Breschet found with their thermo-electric 
multiplicator that the blood in the left auricle of a turkey was 
1.62° Fahr. higher than the blood in the right auricle. 
19. The heat of the body is depressed several degrees below 
