Observations on smoky chimneys, their causes and cure; with considerations on fuel and stoves / Illustrated with proper figures. By Benjamin Franklin, LL.D.

  • Benjamin Franklin
Date:
1793
Catalogue details

Licence: Public Domain Mark

Credit: Observations on smoky chimneys, their causes and cure; with considerations on fuel and stoves / Illustrated with proper figures. By Benjamin Franklin, LL.D. Source: Wellcome Collection.

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    nev with the fmoke; but in the aove, it is obliged to defcend in flame, and pais through the long winding horizontal palTages, commu- nicating its heat to a body of iron plate, which having thus time to receive the heat, commu- nicates the fame to the air of the room, and thereby warms it to a greater degree. 3. The whole of the fuel is confumed by be- ing turned into flame, and you have the benefit of its heat; whereas in common chimneys a great part goes away in fmoke, which you fee Is it rifes, but it affords you no rays of warmth. One may obtain fome notion of the quantity of fuel thus wafted in fmoke, by refledting on the quantity of foot; that a few weeks firing will lodge againft the fides of the chimney, and yet this is formed only of thofe particles of the column of fmoke that happen to touch the fides in its afcent. How much more muff have paffed off in the air ? And we know that this foot is ftill fuel; for it will burn and flame as fuch, and when hard caked together, is indeed very like, and almoft as folid as the coal it proceeds from.* The deftrudion of your fuel goes on nearly in the fame quantity whether in fmoke or in flame : but there is no comparifon in the dif- ference of heat given. Obferve when frefh coals are flrft put on your fire, what a body of fmoke arifes. This fmoke is for a long time too cold to take flame. If you then plunge a burning candle into it, the candle, inftead of inflaming the fmoke, will inftantly be itfelf extinguifhed. Smoke muff have a certain degree of heat to be
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