Memoirs of Benjamin Franklin; Written by Himself. [Vol. 2 of 2] With his Most Interesting Essays, Letters, and Miscellaneous Writings; Familiar, Moral, Political, Economical, and Philosophical, Selected with Care from All His Published Productions, and Comprising Whatever Is Most Entertaining and Valuable to the General Reader

By Benjamin Franklin

Page 222

of the
fluids in an animal quickens the separation, and reproduces more of the
fire, as exercise; that all the fire emitted by wood and other
combustibles, when burning, existed in them before in a solid state,
being only discovered when separating; that some fossils, as sulphur,
seacoal, &c., contain a great deal of solid fire; and that, in short,
what escapes and is dissipated in the burning of bodies, besides water
and earth, is generally the air and fire that before made parts of the
solid. Thus I imagine that animal heat arises by or from a kind of
fermentation in the juices of the body, in the same manner as heat
arises in the liquors preparing for distillation, wherein there is a
separation of the spirituous from the watery and earthy parts. And it is
remarkable, that the liquor in a distiller's vat, when in its best and
highest state of fermentation, as I have been informed, has the same
degree of heat with the human body: that is, about 94 or 96.

Thus, as by a constant supply of fuel in a chimney you keep a warm room,
so by a constant supply of food in the stomach you keep a warm body;
only where little exercise is used the heat may possibly be conducted
away too fast; in which case such materials are to be used for clothing
and bedding, against the effects of an immediate contact of the air, as
are in themselves bad conductors of heat, and, consequently, prevent its
being communicated through their substance to the air. Hence what is
called _warmth_ in wool, and its preference on that account to linen,
wool not being so good a conductor; and hence all the natural coverings
of animals to keep them warm are such as retain and confine the natural
heat in the body by being bad conductors, such as wool, hair, feathers,
and the silk by which the silkworm, in its tender embryo state, is first
clothed. Clothing, thus considered, does not make a man warm by _giving_
warmth, but by _preventing_ the too quick dissipation of the heat
produced in his body, and so occasioning an accumulation.

There is another curious question I will just venture to touch upon,
viz., Whence arises the sudden extraordinary degree of cold,
perceptible on mixing some chymical liquors, and even on mixing salt and
snow, where the composition appears colder than the coldest of the
ingredients? I have never seen the chymical mixtures made, but salt and
snow I have often mixed myself, and am fully satisfied that the
composition feels much

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Text Comparison with Benjamin Franklin and the First Balloons

Page 0
In general it may be said that, whereas Bigelow gives the text without paragraphs, capital letters or the old spelling,[2] Smyth follows the originals more closely.
Page 1
The Champ de Mars being surrounded by Multitudes, and vast Numbers on the opposite Side of the River.
Page 2
Since writing the above, I am favour'd with your kind Letter of the 25th.
Page 3
The great one of M.
Page 4
It carried under it a large Lanthorn with inscriptions on its sides.
Page 5
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The Persons who were plac'd in the Gallery made of Wicker, and attached to the Outside near the Bottom, had each of them a Port thro' which they could pass Sheaves of Straw into the Grate to keep up the Flame, & thereby keep the Balloon full.
Page 7
I was happy to see him safe.
Page 8
We should not suffer Pride to prevent our progress in Science.
Page 9
With great and sincere Esteem, I am, Dear Sir, Your most obed^t & most humble Servant, B.
Page 10
The Wind was very little, so that the Object, tho' moving to the Northward, continued long in View; and it was a great while before the admiring People began to disperse.
Page 11
With great Esteem, I am, Dear Sir, Your most obedient & most humble servant, B.
Page 12
Elle perdoit legerement par une petite ouverture qui existoit deja quelques heures avant son Depart aupres de l'appendice, et dont le Morceau de Taffetas que l'on y avoit applique au moment de l'experience, s'etoit detache.
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le Chevalier de Cubiere.
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" was corrected to ".