30 DESCRIPTION OF A STOVE. 



of the fire-place is fruit, and the key R, fig. 6 is turned, as 

 foon as the wood is reduced to charcoal. Ten hours after the 

 air throughout the room is at a temperature above the mean ; 

 and the centigrade thermometer, placed 36 centimetres (above 

 13 inches) from the ftove, riles rapidly to 16 or 17 degrees. 



To (hew ft ill more plainly to what degree the economy of 

 fuel and prefervation of heat may be carried by this conftruc- 

 tion, I (hall relate another experiment, which I have repeated 

 on feveral occafions, and which has always afforded me very 

 nearly the fame refults. 



The thermometer in the room, in which there was no fire 

 the day before, being between 9 and 10 degrees, a log fawn 

 in three as ufual was put into the fire-place about eleven in the 

 morning; and at three in the afternoon a fimilar quantity of 

 fuel was put in. 



At four o'clock the thermometer, placed at the diftance 

 above-mentioned, was at 42 degrees. 



At five, at 37 degrees. 

 At feven, 34. 

 At nine, 3 1 . 



At midnight, 26. 

 You could not bear to touch with the hand the iron rim of 

 the heat openings. The bulb of the thermometer being placed 

 oppolite one of thefe openings, at the diftance of 8 centime- 

 tres (about 3 inches) rofe in four minutes to 35°. 



The next morning at 9 o'clock the thermometer, which had 

 been again placed at the diftance of 35 centimetres, was at 22 p v 

 Finally at noon, that is to fay twenty-one hours after the 

 laft wood was put in, and eighteen hours after the key had 

 been turned, all the wood being reduced to charcoal, the 

 thermometer ftood between 18 p and 19 p . It was then placed 

 two centimetres only from one of the heat openings, and in 

 lefs than fix minutes it rofe to 26°. 



Thefe effects are fo different from what we commonly ob- 

 tain by the confumption of three or four times as much fuel, 

 that I may expect more than one reader to fuppofe them ex- 

 aggerated ; but I hope a fufficient number will be found dif- 

 pofed to make a trial of thefe ftoves, that their teftimony and 

 example may at length triumph over our habits, and produce 

 a general conviction, that, without differing any privation our- 

 felves, we may preferve for our offspring what ufelefs wafte is 

 daily robbing them of in an article of the firft neceflity. 



VII. A Con- 



