The Works of Benjamin Franklin, Volume 2. Бенджамин Франклин

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СКАЧАТЬ which have no opening in the room where they are used, but the fire is put in from some other room, or from without.

      6. Iron pots, with open charcoal fires, placed in the middle of a room.

      1. The first of these methods has generally the conveniency of two warm seats, one in each corner; but they are sometimes too hot to abide in, and, at other times, incommoded with the smoke; there is likewise good room for the cook to move, to hang on pots, &c. Their inconveniences are that they almost always smoke, if the door be not left open; that they require a large funnel, and a large funnel carries off a great quantity of air, which occasions what is called a strong draft to the chimney, without which strong draft the smoke would come out of some part or other of so large an opening, so that the door can seldom be shut; and the cold air so nips the backs and heels of those that sit before the fire, that they have no comfort till either screens or settles are provided (at a considerable expense) to keep it off, which both cumber the room and darken the fireside. A moderate quantity of wood on the fire in so large a hearth seems but little, and in so strong and cold a draft warms but little; so that people are continually laying on more. In short, it is next to impossible to warm a room with such a fire-place; and I suppose our ancestors never thought of warming rooms to sit in; all they purposed was to have a place to make a fire in, by which they might warm themselves when cold.

      2. Most of these old-fashioned chimneys in towns and cities have been, of late years, reduced to the second sort mentioned, by building jambs within them, narrowing the hearth, and making a low arch or breast. It is strange, methinks, that though chimneys have been so long in use, their construction should be so little understood till lately, that no workman pretended to make one which should always carry off all smoke, but a chimney-cloth was looked upon as essential to a chimney. This improvement, however, by small openings and low breasts, has been made in our days; and success in the first experiments has brought it into general use in cities, so that almost all new chimneys are now made of that sort, and much fewer bricks will make a stack of chimneys now than formerly. An improvement so lately made may give us room to believe that still farther improvements may be found to remedy the inconveniences yet remaining. For these new chimneys, though they keep rooms generally free from smoke, and, the opening being contracted, will allow the door to be shut, yet, the funnel still requiring a considerable quantity of air, it rushes in at every crevice so strongly as to make a continual whistling or howling; and it is very uncomfortable, as well as dangerous, to sit against any such crevice. Many colds are caught from this cause only, it being safer to sit in the open street; for then the pores do all close together, and the air does not strike so sharply against any particular part of the body.

      The Spaniards have a proverbial saying:

      If the wind blows on you through a hole,

      Make your will, and take care of your soul.

      Women particularly, from this cause, as they sit much in the house, get colds in the head, rheums, and defluctions, which fall into their jaws and gums and have destroyed early many a fine set of teeth in these northern colonies. Great and bright fires do also very much contribute to damage the eyes, dry and shrivel the skin, and bring on early the appearances of old age. In short, many of the diseases proceeding from colds, as fevers, pleurisies, &c., fatal to very great numbers of people, may be ascribed to strong-drawing chimneys, whereby, in severe weather, a man is scorched before, while he is froze behind. ^{Ref. 024} In the mean time very little is done by these chimneys towards warming the room; for the air round the fire-place, which is warmed by the direct rays from the fire, does not continue in the room, but is continually crowded and gathered into the chimney by the current of cold air coming behind it, and so is presently carried off.

      In both these sorts of fire-places, the greatest part of the heat from the fire is lost; for, as fire naturally darts heat every way, the back, the two jambs, and the hearth drink up almost all that is given them, very little being reflected from bodies so dark, porous, and unpolished; and the upright heat, which is by far the greatest, flies directly up the chimney. Thus five sixths at least of the heat (and consequently of the fuel) is wasted, and contributes nothing towards warming the room.

      3. To remedy this the Sieur Gauger gives, in his book entitled La Méchanique de Feu, published in 1709, seven different constructions of the third sort of chimneys mentioned above, in which there are hollow cavities, made by iron plates in the back, jambs, and hearths, through which plates the heat passing warms the air in those cavities, which is continually coming into the room fresh and warm. The invention was very ingenious, and had many conveniences; the room was warmed in all parts, by the air flowing through the heated cavities; cold air was prevented rushing through the crevices, the funnel being sufficiently supplied by those cavities; much less fuel would serve, &c. But the first expense, which was very great, the intricacy of the design, and the difficulty of execution, especially in old chimneys, discouraged the propagation of the invention; so that there are, I suppose, very few such chimneys now in use. The upright heat, too, was almost all lost in these, as in the common chimneys.

      4. The Holland iron stove, which has a flue proceeding from the top, and a small iron door opening into the room, comes next to be considered. Its conveniences are, that it makes a room all over warm; for, the chimney being wholly closed except the flue of the stove, very little air is required to supply that, and therefore not much rushes in at crevices, or at the door when it is opened. Little fuel serves, the heat being almost all saved; for it rays out almost equally from the four sides, the bottom, and the top, into the room, and presently warms the air around it, which, being rarefied, rises to the ceiling, and its place is supplied by the lower air of the room, which flows gradually towards the stove, and is there warmed, and rises in its turn, so that there is a continual circulation till all the air in the room is warmed. The air, too, is gradually changed by the stove-door’s being in the room, through which part of it is continually passing, and that makes these stoves wholesomer or at least pleasanter than the German stoves, next to be spoken of. But they have these inconveniences. There is no sight of the fire, which is in itself a pleasant thing. One cannot conveniently make any other use of the fire but that of warming the room. When the room is warm, people, not seeing the fire, are apt to forget supplying it with fuel till it is almost out, then, growing cold, a great deal of wood is put in, which soon makes it too hot. The change of air is not carried on quite quick enough; so that, if any smoke or ill smell happens in the room, it is a long time before it is discharged. For these reasons the Holland stove has not obtained much among the English (who love the sight of the fire) unless in some workshops, where people are obliged to sit near windows for the light, and in such places they have been found of good use.

      5. The German stove is like a box, one side wanting. It is composed of five iron plates, screwed together, and fixed so as that you may put the fuel into it from another room, or from the outside of the house. It is a kind of oven reversed, its mouth being without, and body within, the room that is to be warmed by it. This invention certainly warms a room very speedily and thoroughly with little fuel; no quantity of cold air comes in at any crevice, because there is no discharge of air which it might supply, there being no passage into the stove from the room. These are its conveniences. Its inconveniences are, that people have not even so much sight or use of the fire as in the Holland stoves, and are, moreover, obliged to breathe the same unchanged air continually, mixed with the breath and perspiration from one another’s bodies, which is very disagreeable to those who have not been accustomed to it.

      6. Charcoal fires in pots are used chiefly in the shops of handicraftsmen. They warm a room (that is kept close, and has no chimney to carry off the warmed air) very speedily and uniformly; but, there being no draft to change the air, the sulphurous fumes from the coals (be they ever so well kindled before they are brought in, there will be some) mix with it, render it disagreeable, hurtful to some constitutions, and sometimes, when the door is long kept shut, produce fatal consequences.

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