342 
POPULAR SCIENCE REVIEW. 
08 3 Fakr. in temperature, even under violent exercise ; for 
a copious flow of perspiration carries off the heat so generated. 
And for the same reason it is possible in dry air to bear with 
impunity a degree of heat much beyond what could be borne in 
moist ah’, where the perspiration would not be vaporised as 
fast as excreted. Water, at the temperature of 120° is almost 
unbearable. A vapour bath at the same temperature might be 
endured for a few minutes ; but the distress arising from the 
suppressed perspiration would soon render it intolerable. But 
in dry air a heat can be borne with impunity, and almost 
without discomfort, which will roast eggs and dress beafsteaks. 
In some experiments performed by Drs. Watson and Carpenter, 
it became desirable to ascertain the height at which a thermo- 
meter stood in an oven, -without subjecting it to the cooling- 
consequent on withdrawing it. A girl volunteered to go into 
the oven and mark the height of the mercury. The gentlemen 
hesitated at her proposal; but she assured them she was not in 
the least afraid of so doing ; and she actually went in, and re- 
mained there for ten minutes, while the thermometer stood at 
280° ; and another girl remained for five minutes in the oven 
with the thermometer at 325°, or 113° above the point of 
boiling water. Beefsteaks were cooked in this oven, merely by 
the temperature of the air, in thirty-three minutes ; and when 
the ah- was blown on them by a pair of bellows, they were 
cooked in thirteen minutes. And yet in these experiments the 
young women suffered scarcely any inconvenience ; and the 
heat of the body, as tried by a thermometer placed under the 
tongue, was scarcely at all increased. Sir Charles Blagden re- 
mained for some minutes in air of about the same temperature, 
and also Dr. Lankester ; and Chabert, the French showman, 
called the Fire King, was in the habit of entering an oven 
heated from 400° to 600°, or within a few degrees of the heat 
of molten lead. Animals covered -with hair or feathers, how- 
ever, die very soon in temperatures much below these ; appa- 
rently because the hair or feathers interfere -with the free escape 
of moisture from the skin, which is necessary to keep the blood 
cool, and prevent injurious consequences. Hence, also, persons 
who are in the habit of taking Turkish baths, which are, in fact, 
hot-air baths, experience no inconvenience from the high tem- 
perature as soon as the perspiration begins to flow, which, in a 
practised bather, it does immediately. 
The amount of liquid which, in a person in health, issues from 
the pores during- the twenty-four hours is not less than an im- 
perial pint, containing about an ounce of solid matter in solution, 
and besides a large amount of carbonic acid gas : hence we can 
estimate the importance of keeping these ducts in perfect order 
by means of frequent bathing. 
