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time, very little is done by these chimneys to- | ing warms the air in those cavities which is wards warming the room; for the air round continually coming into the room fresh and the fire-place, which is warmed by the direct warm. The invention was very ingenious, rays from the fire, does not continue in the and had many inconveniences: the room was room, but is continually crowded and gather- warmed in all parts, by the air flowing into it ed into the chimney by the current of cold through the heated cavities: cold air was air coming behind it, and so is presently car- prevented rushing through the crevices, the ried off.
funnel being sufficiently supplied by those caIn both these sorts of fire-places, the great- vities: much less fuel would serve, &c. But est part of the heat from the fire is lost; for as the first expense, which was very great, the fire naturally darts heat every way, the back, intricacy of the design, and the difficulty of the two jambs, and the hearth, drink up al- the execution, especially in old chimneys, dismost all that is given them, very little being couraged the propagation of the invention; so reflected from bodies so dark, porous, and un- that there are, I suppose, very few such chimpolished; and the upright heat, which is by neys now in use. The upright heat, too, was far the greatest, flies directly up the chimney. almost all lost in these, as in the common Thus five sixths at least of the heat (and con- chimneys. sequently of the fuel) is wasted, and contri The Holland iron stove, which has a flue butes nothing towards warming the room. proceeding from the top, and a small iron
3. To remedy this, the sieur Gauger gives, door opening into the room, comes next to be in his book entitled, La Mechanique de Feu, considered. Its conveniences are, that it published in 1709, seven different construc- makes a room all over warm; for the chimtions of the third sort of chimneys mentioned ney being wholly closed, except the flue of above, in which there are hollow cavities the stove, very little air is required to supply made by iron plates in the back, jambs, and that, and therefore not much rushes in at hearths, through which plates the heat pass- crevices, or at the door when it is opened.
Little fuel serves, the heat being almost all first case, the shock the body endures, is general, uni- saved ; for it rays out almost equally from form, and therefore less fierce; in the other, a single the four sides, the bottom and the top, into part, a neck, or ear perchance, is attacked, and that the room, and presently warms the air around successive stream of cold air. And the cannon of a it, which, being rarefied, rises to the ceiling, battery, pointed against a single part of a bastion, will and its place is supplied by the lower air' of singly upon the whole face, and will admit an enemy the room, which flows gradually towards the
stove, and is there warmed, and rises in its That warm rooms, and keeping the body warm in winter, are means of preventing such diseases, lake turn, so that there is a continual circulation the opinion of that learned Italian physician Antonino till all the air in the room is warmed. The Parcio, in the preface to his tract de Militis Sanitate tu: air, too, is gradually changed, by the stoveter, remarkable at Venice for its sickliness, he says, door's being in the room, through which part ** Popularis autem pleuritis quæ Venetiis sæviit mensi- of it is continually passing, and that makes bus Dec. Jan. Feb. ex cæli, aërisque inclementia facta these stoves wholesomer, or at least pleasanter non soliciti sunt Itali omnes de auribus, temporibus, than the German stoves, next to be spoken collo, totoque corpore defendendis ab injuriis aëris; et of. But they have these inconveniences. ut nives diutius permaneant super tegmina. E contra, There is no sight of the fire, which is in itself
qui experiuntur cæli inclementiam, perdidi: a pleasant thing. One cannot conveniently cere sese defendere ob aëris injuria. Tecta construunt make any other use of the fire but that of dant lignis, domusque hypocaustis ; foris autem ince. warming the room. When the room is warm, dunt pannis pellibus, gossipio, bene mehercule loricati people, not seeing the fire, are apt to forget motus videndi Germaniam) quot nam elapsis mensibus supplying it with fuel till it is almost out, pleuritide vel peripneumonia fuissent absumti: dice: then growing cold, a great deal of wood is put bant vix unus aut alter illis temporibus pleuritide fuit in, which soon makes it too hot. The change correptus.
The great Dr. Boerhaave, whose authority alone of air is not carried on quite quick enough, so might be sufficient, in his Aphorisms, mentions, as one that if any smoke or ill smell happens in the lently through some narrow passage upon the body, room, it is a long time before it is discharged.
For these reasons the Holland stove has not The eastern physicians agree with the Europeans in obtained much among the English (who love Tschang seng ; i. e. The Art of procuring Health and the sight of the fire) unless in some workshops, long Life, as translated in Pere Du Halde's account of where people are obliged to sit near windows China, which has this passage. As, of all the passions for the light, and in such places they have which ruffle us, anger does the most mischief,so of all ma. lignant affections of the air, a wind that comes through been found of good use. any narrow passage, which is cold and piercing, is most 5. The German stove is like a box, one side dangerous; and coming upon us unawares insinuates itself into the body, often causing grievous diseases. wanting. It is composed of five iron plates It should therefore be avoided, according to the advice screwed together, and fixed so as that you arrow.” These mischiefs are avoided by the use of the may put the fuel into it from another room, new.invented fire-places, as will be shown hereafter. or from the outside of the house. It is a kind
much sooner into the town."
of oven reversed, its mouth being without, , edges of the back plate, the two side plates, and body within the room that is to be warm- and the two middle plates. These ledges are ed by--it. This invention certainly warms a about an inch asunder, and about half an room very speedily and thoroughly with little inch high; a profile of two of them, joined to a fuel: no quantity of cold air comes in at any fragment of plate, appears in Fig. 3. crevice, because there is no discharge of air (ii.) The back plate is without holes, havwhich it might supply, there being no passage ing only a pair of ledges on each side, to reinto the stove from the room. These are its ceive the back edges of the two. conveniences. Its inconveniences are, that (iii iii.) Side plates : these have each a people have not even so much sight or use of pair of ledges to receive the side edges of the the fire as in the Holland stoves, and are, front plate, and a little shoulder for it to rest moreover, obliged to breathe the same un on; also two pair of ledges to receive the side changed air continually, mixed with the edges of the two middle plates which form the breath and perspiration from one another's air box; and an oblong air-hole near the top, bodies, which is very disagreeable to those through which is discharged into the room who have not been accustomed to it.
the air warmed in the air-box. Each has also 6. Charcoal fires in pots are used chiefly a wing or bracket, H and I, to keep in falling in the shops of handicraftsmen. They warm brands, coals, &c. and a small hole, Q and R, a room (that is kept close, and has no chim- for the axis of the register to turn in. ney to carry off the warmed air) very speedi (iv iv.) The air-box is composed of the two ly and uniformly; but there being no draught middle plates, D E and F G. The first has to change the air, the sulphurous fumes from five thin ledges or partitions cast on it, two the coals, [be they ever so well kindled before inches deep, the edges of which are received they are brought in, there will be some,] mix in so many pair of ledges cast in the other.with it, render it disagreeable, hurtful to some The tops of all the cavities formed by these constitutions, and sometimes, when the door thin deep ledges, are also covered by a ledge of is long kept shut, produce fatal consequences. the same form and depth, cast with them ; so
To avoid the several inconveniences, and at that when the plates are put together, and the the same time retain all the advantages of joints luted, there is no communication beother fire-places, was contrived the Pennsyl- tween the air-box and the smoke. In the vanian fire place, now to be described. winding passages of this box, fresh 'air is This machine consists of
warmed as it passés into the room. A bottom plate, (i), (See the plate annex (v.) The front plate is arched on the under ed.)
side, and ornamented with foliages, &c. it has Á back plate, (ii)
no ledges. Two side plates, (iii iii)
(vi.) The top plate has a pair of ears, M N, Two middle plates, (iv iv) which, joined answerable to those in the bottom plate, and together, form a tight box, with winding pas perforated for the same purpose : it has also sages in it for warming the air.
a pair of ledges running round the under side A front plate, (v)
to receive the top edges of the front, back, and A top plate, (vi.)
side plates. The air-box does not reach up These are all cast of iron, with mouldings the top plate by two inches and a half. or ledges where the platés come together, to (vii.) The shutter is of thin wrought iron hold them fast, and retain the mortar used for and light, of such a length and breadth as to pointing to make tight joints. When the close well the opening of the fire-place. It is plates are all in their places, a pair of slender used to blow up the fire, and to shut up and rods, with screws, are sufficient to bind the secure it at nights. It has two brass knobs whole very firmly together, as it appears in for handles, d d, and commonly slides up and Fig. 2.
and down in a groove, left, in putting up the There are, moreover, two thin plates of fire-place, between the foremost ledge of the wrought iron, viz. the shutter, (vii) and the side plates, and the face of the front plate; register, (viii;) besides the screw-rods O P, but some choose to set it aside when is not all which we shall explain in their order. in use, and apply it on occasion.
(i.) The bottom plate, or hearth-piece, is (viii.). The register is also of thin wrought. round before, with a rising moulding, that iron. It is placed between the back plate serves as a fender to keep coals and ashes from and air-box, and can, by means of the key S, coming to the floor, &c. It has two ears, FG, be turned on its axis so as to lie in any position perforated to receive the screw rods OP; a between level and upright. long air-hole, a a, through which the fresh The screw-rods 0 P are of wrought iron, outward air passes up into the air box; and about a third of an inch thick, with a button three smoke holes BC, through which the at bottom, and a screw and nut at top, and smoke descends and passes away; all repre- may be ornamented with two small brasses sented by dark squares. It has also double screwed on above the nuts. ledges to receive between them the bottom To put this machine to work,
1. A false back of four inch (or, in shallowing specifically lighter than the other air in small chimneys, two inch) brick work is to be the room, is obliged to rise; but the closure made in the chimney, four inches or more from over the fire-place hindering it from going up the true back: from the top of this false back the chimney, it is forced out into the room, a closing is to be made over to the breast of rises by the mantle-piece to the ceiling, and the chimney, that no air may pass into the spreads all over the top of the room, whence chimney, but what goes under the false back, being crowded down gradually by the stream and
up behind it.
of newly-warmed air that follows and rises 2. Some bricks of the hearth are to be taken above it, the whole room becomes in a short up, to form a hollow under the bottom plate; time equally warmed. across which hollow runs a thin tight partition, At the same time the air, warmed under to keep apart the air entering the hollow and the bottom plate, and in the air-box, rises and the smoke; and is therefore placed between comes out of the holes in the side-plates, very the air-hole and smoke-holes.
swiftly, if the door of the room be shut, and 3. A passage is made, communicating with joins its current with the stream before-menthe outward air, to introduce that air into the tioned, rising from the side, back, and top forepart of the hollow under the bottom plate, plates. whence it may rise through the air-hole into The air that enters the room through the the air-box.
air-box is fresh, though warm; and, comput4. A passage is made from the back part ing the swiftness of its motion with the areas of the hollow, communicating with the fue of the holes, it is found that near ten barrels behind the false back: through this passage of fresh air are hourly introduced by the airthe smoke is to pass.
box; and by this means the air in the room The fire-place is to be erected upon these is continually changed, and kept, at the same hollows, by putting all the plates in their time, sweet and warm. places, and screwing them together.
It is to be observed, that the entering air Its operation may be conceived by observing will not be warm at first lighting the fire, the plate entitled, Profile of the Chimney and but heats gradually as the fire increases. Fire-place.
A square opening for a trap-door should be M The mantle-piece, or breast of the chim- left in the closing of the chimney, for the ney:
sweeper to go up: the door may be made of C The funnel.
slate or tin, and commonly kept close shut, B The false back and closing.
but so placed as that, turning up against the E True back of the chimney.
back of the chimney when open, it closes the T Top of the fire-place.
vacancy behind the false back, and shoots the F The front of it.
soot, that falls in sweeping, out upon the A The place where the fire is made. hearth. This trap-door is a very convenient D The air-box.
thing. K The hole in the side-plate, through which In rooms where much smoking of tobacco is the warmed air is discharged out of the air- used, it is also convenient to have a small box into the room.
hole, about five or six inches square, cut near H The hollow filled with fresh air, entering the ceiling through into the funnel: this hole at the passage 1, and ascending into the air- must have a shutter, by which it may be closed box through the air-hole in the bottom plate or opened at pleasure. When open, there
will be a strong draught of air through it inG The partition in the hollow to keep the to the chimney, which will presently carry air and smoke apart.
off a cloud of smoke, and keep the room clear ; P The passage under the false back and if the room be too hot likewise, it will carry part of the hearth for the smoke.
off as much of the warm air as you please, The arrows show the course of the smoke. and then you may stop it entirely, or in part,
The fire being made at A, the flame and as you think fit. By this means it is, that the smoke will ascend and strike the top T, which tobacco smoke does not descend among the will thereby receive a considerable heat. The heads of the company near the fire, as it must smoke, finding no passage upwards, turns over do before it can get into common chimneys. the top of the air-box, and descends between it and the back plate to the holes in the bot
The manner of using this Fire-place. tom plate, heating, as it passes, both plates of Your cord-wood must be cut into three the air-box, and the said back plate; the front lengths; or else a short piece, fit for the fireplate, bottom and side plates are also all heated place, cut off, and the longer left for the kitchat the same time. The smoke proceeds in en or other fires. Dry hickory, or asb, or any the passage that leads it under and behind the woods that burn with a clear flame are rather false back, and so rises into the chimney. The to be chosen, because such are less apt to foul air of the room, warmed behind the back plate, the smoke-passages with soot: and flame comand by the sides, front, and top plates, becom- municates with its light, as well as by contact,