STOVE. 
609 
oil end, that are a foot long, and four inches square: the 
tiles, too, join into each other, by ridges and hollows along 
their sides. This forms a hollow under the whole floor, 
which on one side of the house has an opening into the air, 
where a fire is made; and it has a funnel rising from the 
other side to carry off the smoke. The fuel is a sulphurous 
pit-coal, the smell of which in the room is thus avoided, 
while the floor, and of course the room, are well warmed. 
Francis Keslar, of Frankfort, whose work, entitled 
“ Epargne-bois,” &c. (the Wood-saver, &c.), appeared, 
in French, in 1619, is the oldest writer who deserves to be 
quoted, as having proposed any useful ideas on the subject of 
stoves. He formed eight chambers, one above another, 
through which the smoke was to pass before it entered the 
chimney. He also brought air directly from without into 
the ash-pan, to feed the fire; and there was another aperture 
to draw air from the apartment for the same purpose. 
M. Dalesme, in 1686, suggested the first idea of a stove 
without smoke, which he called funius acapnos. Here the 
smoke is forced to descend into the fire-place, where it is 
consumed. 
This machine consisted of a tube of iron-plate, such as is 
used for the flue of a German stove. This tube was bent at 
right angles, and the part which was horizontal was about 
two feet in length, and joined to the rest of the tube, which 
ascended vertically. At the opposite end of the horizontal 
tube the furnace was made : it consisted of a cylindrical tube 
of plate-iron erected upon the horizontal tube near the end, 
and provided with a grating, upon which the fuel was placed ; 
and the grate prevented the fuel falling down into the hori¬ 
zontal tube. To light this stove, some clear burning charcoal 
was put into the large short tube or furnace, and supported 
on ihe grate. As soon as the tubes grew warm, the air within 
them vvould ascend in the perpendicular tube or chimney, 
and go out at the top of it; fresh air must enter into the 
horizontal tube through the furnace. In this course it must 
descend through the burning fuel, and becoming heated by 
the burning coals, through which it has passed, would rise 
more forcibly in the longer tube, in proportion to its degree 
of heat, or rarefaction, and the length of that tube. Such a 
machine is a kind of inverted siphon ; and as the greater 
weight of water in the longer leg of the common siphon, in 
descending, is accompanied by an ascent of the same fluid in 
the shorter ; so in this inverted siphon, the greater quantity 
of levity of air in the longer leg, in rising, is accompanied by 
the descent of air in the shorter. The things to be burned 
being laid on the hot coals contained in the furnace, the 
smoke must descend through those coals, and be converted 
into flame, which, after destroying the offensive smell, comes 
out at the end of the longer tube, as mere heated transparent 
gas or vapour. 
Whoever would repeat this experiment with success, must 
take care that the part of the short tube is quite full of burn¬ 
ing coals, so that no part of the smoke may descend and pass 
by them, without going through them, and being converted 
into flame; and that the longer tube is so heated, that the 
current of ascending hot air will be established in it, before 
the things to be burnt are laid on the coals; otherwise there 
will be disappointment. 
It does not appear that this idea was followed up either in 
England or France, but there is a German book, entitled 
<! Vulcanus Famulans,” by Joh. George Leutmann, printed 
at Wirtemburg in 1723, which describes, among a great 
variety of other stoves for warming of rooms one which 
seems to have been formed on the same principle. The con¬ 
struction is as nearly as possible the same as M. Dalesme’s, 
except in the proportion of the parts; Leutmann’s furnace 
being made in the form of a basin or vase, having the grate 
in the bottom of it. 
Gauger, author of “ La Mechanique du Feu,” &c,, printed 
at Paris in 1709, was the person to whom we are indebted 
for the first and most complete system of experiments on the 
circulation of heat, by means of air-holes affording warm 
air; as also the manner of making one fire warm several 
Vor,. XXIII. No. 1594. 
rooms, and to send off the heat in elliptic curves. We there 
find a description of a chimney, with the back, the hearth, 
and the jambs, of hollow iron, to heat the air that is to enter 
the room. But it does not appear that this work produced 
much effect at the time. 
The inhabitants of the’northern parts of Europe have 
long been accustomed to the use of stoves in which the fire 
is shut up, and gives out its heat to a draught or current 
of air, which is made to pass through proper openings in 
the stove, and when sufficiently warmed, enters into the 
apartment. The smoke arising from the fuel is made to pass 
through a circuitous passage of flues, by which means the 
greatest part of the heat is absorbed. Stoves on this prin¬ 
ciple are known in England, but are very seldom used, 
except for warming of halls, staircases, and passages, in grand 
houses, as the English are not contented to feel the air warm, 
unless they see the fire. In Russia, Sweden, and other 
northern countries, they are indispensably necessary, as with¬ 
out them, it would be impossible to keep the rooms tolerably 
warm. A common fire-place has too large an opening, and 
if care be not taken to supply it continually with wood, 
&c., the heat it produces is hardly sensible, because this 
follows the current of the air, and is carried off bv the 
smoke. These stoves, on the contrary, retain the heat a 
much longer time; and as their external parts, and also their 
flues, are very thin, they communicate their heat very readily, 
so that with a small quantity of wood, they warm an apart- 
much more than the fire of a common fire-place would do 
with six times the quantity. 
It has been objected to the use of stoves that the heat pro¬ 
duced from them is unwholesome, because they deprive the 
air of its moisture ; and that the air, by being made too dry, 
loses its elasticity, in consequence of which, respiration be¬ 
comes difficult and laborious. These objections would ap¬ 
pear of great weight, if we had not the example of the Rus¬ 
sians, the Swedes, the Danes, the Germans, and in short 
of all the inhabitants of the north of Europe, to shew that 
those who are habituated to such stoves, do not find them 
unwholesome. If others should be sensible of inconvenien¬ 
ces from the dryness of the air in the apartment, it may be 
easily removed by the very simple expedient of placing 
upon the stove a vessel of glass or earthen-ware, which has 
a large surface, and is very shallow: this being filled with 
water, will insensibly evaporate, and restore to the air that 
moisture of which the heat of the stove has deprived it: the 
air will then recover its elasticity. If orange-trees are ex¬ 
posed to the heat of such a stove, and the fire is not pro¬ 
perly regulated, the plants grow yellow and lose their leaves, 
especially if the air is not changed, which in winter is not 
very conveniently done; but if a vessel of water be placed 
upon the stove, the evaporation of the water will perserve 
the trees. 
In a memoir published by M. Guyton, in the Annales de 
Chimie, the following principles are laid down, as very 
useful in making all kinds of stoves for warming apartments. 
1. Heat is produced only in proportion to the volume of 
air consumed by the fuel. 
2. The quantity of heat produced is greatest, (the quan¬ 
tity and quality of the fuel being the same), when the com¬ 
bustion is complete. 
3. The combustion is the more complete, in proportion 
as the fuliginous part is longer retained in channels where 
it may undergo a second combustion. 
4. The only useful heat is that sent out into, and re¬ 
tained in the space intended to be heated. The tempera¬ 
ture of that space will be higher in proportion, as the cu- 
rent which must be renewed from without to support the 
combustion, is less enabled to take up in its passage the heat 
produced. 
Hence the following inferences evidently arise: 
1. The fire-place ought to be insulated from all bodies 
that are rapid conductors of heat. All the heat that goes 
out of the apartment is absolutely lost, unless intentionally 
directed into another apartment. 
7 Q 2. Heat 
