remarkable Effects of a Shipwreck. 
217 
EXPERIMENT VIII. 
I placed in a large room, where the mercury stood a 4- 36° 
two slipper baths at the distance of six yards from each 
other. One was filled with cold salt-water of the temperature 
of 36°, the other with water heated to 96°, which was my own 
heat. Undressing myself in an adjoining room by a fire, I 
afterwards slipped on a loose flannel dress, and descended 
slowly into the cold bath, where I remained two minutes ; I 
ascended slowly into the air, and then sunk myself in the warm 
bath, where I remained two minutes also : I returned to the 
cold bath, where I staid two minutes as before, and removed 
from it again to the warm bath. But during all these changes 
of media and temperature, the thermometer with its bulb 
under my tongue never varied from 96°. I attribute this 
partly to the heat of my body being in some degree defended 
by the flannel dress, partly to the calm of the air, but chiefly 
to the slowness of motion in these changes. It may be said 
that the time of staying in the different baths was not long 
enough to produce any sensible change in the heat of circu- 
lating fluids of such a mass, but this is not consistent with 
many of the other facts. 
5. The influence of the application of cold water to the 
surface of the body on the heat, is in some respects regulated 
by the animal vigour, as the following experiment will show. 
EXPERIMENT IX. 
In the same room I placed a large empty vessel : in this two 
young men sat down in succession, each with the bulb of a 
thermometer under his tongue. A man standing on a bench 
