PECULIAR SECRETIONS. 381 
body, in one instance, sunk rapidly from 98° te 87°, when 
placed in water at 44°, but at the end of twelve minutes it 
rose to 931°. In another experiment, in water of the same 
temperature, the heat of the body fell from 98°, in the 
course of two minutes to 88°, but, at the end of thirteen mi- 
nutes, it had risen to 96°. Dr Hunter found that a dor- 
mouse, whose heat, in an atmosphere at 64°, was 812°, 
when put into air at 20°, had its temperature raised in 
the course of half an hour to 98°: an hour after, the air 
being 30°, it was stil] 93°: at another hour after, the air 
being 19°, the heat of the pelvis was as low as 83°, but 
the animal was now less lively. In this experiment, the 
dormouse had maintained its temperature about seventy 
degrees higher than the surrounding medium, and for the 
space of two hours and a half. 
In the cold-blooded animals, heat is generated under si- 
milar circumstances. Hunter found that the heat of a 
viper, placed in a vessel at 10°, was reduced in ten minutes 
to 37°, in other ten minutes, the vessel being 13° to 35°, 
and in the next ten minutes, the vessel at 20° to 1°. In 
frogs, he was able to lower the temperature likewise to 
31°, but beyond this point it was not possible to lessen the 
heat, without destroying the animal. 
When the cooling cause is applied to particular parts of 
the body, the heat of these parts sinks lower than the mini- 
mum of depressed temperature of the body. Although 
Honrer was unable to heat the urethra one degree above 
the maximum of the elevated temperature of the body, yet 
he succeeded in cooling it twenty-nine degrees lower than 
the minimum of depressed temperature, viz. to 58°. He 
succeeded in cooling down the ears of rabbits until they 
froze, and when thawed, they recovered their natural heat 
and circulation. ‘The same experiment was performed on 
the comb and wattles of a cock. Though he found that, 
