The singular power which the body possesses of resisting great heats,
and of breathing air of high temperatures, has at various times excited
popular wonder. In the last century some curious experiments were
made on this subject. Sir Joseph Banks, Dr. Solander, and Sir Charles
Blagden, entered a room in which the air had a temperature of 198°
Fahr., and remained ten minutes. Subsequently they entered the room
separately, when Dr. Solander found the heat 210°, and Sir Joseph
211°, whilst their bodies preserved their natural degree of heat.
Whenever they breathed upon a thermometer, it sank several degrees;
every inspiration gave coolness to their nostrils, and their breath
cooled their fingers when it reached them. Sir Charles Blagden entered
an apartment when the heat was 1° or 2° above 260°, and remained eight
minutes, mostly on the coolest spot, where the heat was above 240°.
Though very hot, Sir Charles felt no pain: during seven minutes his
breathing was good; but he then felt an oppression in his lungs, and
his pulse was 144, double its ordinary quickness. To prove the heat of
the room, eggs and a beefsteak were placed upon a tin frame near the
thermometer, when in twenty minutes the eggs were roasted hard, and in
forty-seven minutes the steak was dressed dry; and when the air was put
in motion by a pair of bellows upon another steak, part of it was well
done in thirteen minutes. It is remarkable, that in these experiments
the same person who experienced no inconvenience from air heated to
211°, could just bear rectified spirits of wine at 130°, cooling oil at
129°, cooling water at 123°, and cooling quicksilver at 117°.
Sir Francis Chantrey, the sculptor, however, exposed himself to a
temperature still higher than any yet mentioned, as described by Sir
David Brewster:
The furnace which he employs for drying his moulds is about
fourteen feet long, twelve feet high, and twelve feet broad. When
it is raised to its highest temperature, with the doors closed,
the thermometer stands at 350°, and the iron floor is red-hot. The
workmen often enter it at a temperature of 340°, walking over the
iron floor with wooden clogs, which are of course charred on the
surface. On one occasion, Mr. Chantrey, accompanied by five or
six of his friends, entered the furnace; and after remaining two
minutes they brought out a thermometer which stood at 320°. Some
of the party experienced sharp pains in the tips of their ears
and in the septum of the nose, while others felt a pain in their
eyes.--_Natural Magic_, 1833.
In some cases the clothing worn by the experimenters conducts away
the heat. Thus, in 1828, a Spaniard entered a heated oven, at the New
Tivoli, near Paris; he sang a song while a fowl was roasted by his
side, he then ate the fowl and drank a bottle of wine, and on coming
out his pulse beat 176°, and the thermometer was at 110° Reaumur. He
then stretched himself upon a plank in the oven surrounded by lighted
candles, when the mouth of the oven was closed; he remained there five
minutes, and on being taken out, all the candles were extinguished and
melted, and the Spaniard’s pulse beat 200°. Now much of the surprise
ceases when it is added that he wore wide woollen pantaloons, a loose
mantle of wool, and a great quilted cap; the several materials of this
clothing being bad conductors of heat.
In 1829 M. Chabert, the “Fire-King,” exhibited similar feats at the
Argyll Rooms in Regent Street. He first swallowed forty grains of
phosphorus, then two spoonfuls of oil at 330°, and next held his head
over the fumes of sulphuric acid. He had previously provided himself
with an antidote for the poison of the phosphorus. Dressed in a loose
woollen coat, he then entered a heated oven, and in five minutes cooked
two steaks; he then came out of the oven, when the thermometer stood at
380°. Upon another occasion, at White Conduit House, some of his feats
were detected.
The scientific secret is as follows: Muscular tissue is an extremely
bad conductor; and to this in a great measure the constancy of the
temperature of the human body in various zones is to be attributed. To
this fact also Sir Charles Blagden and Chantrey owed their safety in
exposing their bodies to a high temperature; from the almost impervious
character of the tissues of the body, the irritation produced was
confined to the surface.
Magnetism and Electricity.