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the smoky fumes, they would remain crowded about the fire, and stifle it.
2. Heat may be separated from the smoke as well as from the light, by means of a plate of iron, which will suffer heat to pass through it without the others.
3. Fire sends out its rays of heat, as well as rays of ught, equally every way; but the greatest sensible heat is over the fire, where there is, besides the rays of heat shot upwards, a continual rising stream of hot air, heated by the rays shot round on every side.
These things being understood, we proceed to consider the fire-places heretofore in use, viz.
1. The large open fire-places used in the days of our fathers, and still generally in the country, and in kitchens.
2. The newer-fashioned fire-places, with low breasts and narrow hearths.
3. Fire-places with hollow backs, hearths and jambs of iron, (described by M. Gauger, in his tract entitled La Méchanique de Feu,) for warming the air as it comes into the room.
4. The Holland stoves, with iron doors opening into the room.
5. The German stoves, 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 fire-side. 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 fireplace; 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 chimThis 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.* In the mean time, very little
* As the writer is neither physician nor philosopher, the reader may expect he should justify these his opinions by the authority of some that are so. M. Clare, F. R. S., in his treatise of The Motion of Fluids, says, (p. 246, &c.) "And here it may be remarked, that it is more prejudicial to health to sit near a window or door, in a room where there are many candles and a fire, than in a room without; for the consumption of air thereby occasioned, will always be very considerable, and this must necessarily be replaced by cold air from without. Down the chimney can enter none, the stream of warm air always arising therein absolutely forbids it; the supply must therefore come in wherever other openings
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,
shall be found. If these happen to be small, let those who sit near them beware; the smaller the floodgate, the smarter will be the stream. Was a man, even in a sweat, to leap into a cold bath, or jump from his warm bed, in the intensest cold, even in a frost, provided he do not continue over-long therein, and be in health when he does this, we see by experience, that he gets no harm. If he sits a little while against a window, into which a successive current of cold air comes, his pores are closed, and he gets a fever. In the first case, the shock the body endures is general, uniform, and therefore less fierce; in the other, a single part, a neck, or ear perchance, is attacked, and that with the greater violence probably, as it is done by a successive stream of cold air. And the cannon of a battery, pointed against a single part of a bastion, will easier make a breach than were they directed to play singly upon the whole face, and will admit the enemy much sooner into the town."
That warm rooms, and keeping the body warm in winter, are means of preventing such diseases, take the opinion of that learned Italian physician, Antonino Parcio, in the preface to his tract De Mililis Sanitale Tuenda, where, speaking of a particular wet and cold winter, remarkable at Venice for its sickliness, he says, "Popularis autem pleuritis, quæ Venetiis sæviit mensibus Dec., Jan., Feb., ex cœli aërisque inclementiâ facta est, quod non habeant hypocausta [slove-rooms], et quod non soliciti sunt Itali omnes de auribus, temporibus, collo, totoque corpore defendendis ab injurus aëris ; et tegmina domorum Veneti disponant parum VOL. VI. D*
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 into it 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 the 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.
inclinata, ut nives diutius permaneant super tegmina. E contra, Germani, qui experiuntur cœli inclementiam, perdidicere sese defendere ab aëris injuria. Tecta construunt multum inclinata, ut decidant nives. Germani abundant lignis, dcmusque hypocaustis; foris autem incedunt pannis, pellibus, gossipio, bene mehercule loricati atque muniti. In Bavariâ interrogabam (curiositate motus videndi Germaniam) quot nam elapsis mensibus pleuritide vel peripneumonià fuissent absumti; dicebant vix unus aut alter illis temporibus pleuritide fuit correptus."
The great Dr. Boerhaave, whose authority alone might be sufficient, in his Aphorisms, mentions, as one antecedent cause of pleurisies, "a cold air, driven violently through some narrow passage upon the body, overheated by labor or fire."
The eastern physicians agree with the Europeans in this point; witness the Chinese treatise, entitled Tschang Seng, that is, The Art of procuring Health and long Life, as translated in Père Du Halde's account of China, which has this passage. “As, of all the passions which ruffle us, anger does the most mischief, so of all the malignant affections of the air, a wind that comes through any narrow passage, which is cold and piercing, is most dangerous; and, coming upon us unawares, insinuates itself into the body, often causing grievous diseases. It should therefore be avoided, according to the advice of the ancient proverb, as carefully as the point of an arrow." These mischiefs are avoided by the use of the new-invented fire-places, as will be shown hereafter.