I must say

forated web or flange on each side, so that the air warmed by the under side of the pipe also can rise through those holes. But even that is very inferior in effect to pipes completely above ground. however that I greatly prefer warming by what are called gill stoves, i.e. those in which a number of wide iron plates stand near together which join at the inner edges so as to enclose the fire. There are two kinds of them; one called Gurney's which are round, with the hot air plates radiating, and the other Stuart and Smith's of Sheffield, where the plates are parallel. And I consider the latter much the best, because they never get overheated; at least I never saw one with the plates too hot to touch, while I never saw a Gurney stove which either was not then or had not evidently been at some time red hot in the lower part; and it is well known that iron much hotter than boiling water burns the air and makes it unwholesome. This is attempted to be prevented by putting a dish of hot water round the bottom of the Gurney stoves, but it clearly often fails; and filling the place with steam is no compensation for burning the air, though it mitigates the effect a little and tends to keep the iron from getting red hot, but not sufficiently. Yet these round stoves somehow or other managed to puff themselves into much more extensive use than the square ones. The patents for both have long expired. They may either be used as independent stoves above ground, or in a separate chamber under ground in connection with channels and gratings for keeping up a distinct circulation of the air to distant parts of the building, and that is thought the best way when it is large. I examined and inquired about all the methods of warming before Stuart and Smith's was adopted in St. George's and

St. James's churches at Doncaster in 1858. There was a wonderful uniformity in the estimates, but I was satisfied that that was on the whole the best though architects generally recommend another. And it is still more decidedly so for a moderate-sized hall where a single stove above ground is sufficient.

Fire-places. No one who has not tried both experiments in the same large room can have any idea of the superiority of grates with only bars in front of a firebrick back and sides over those of any shape in iron: i.e. where the fire-place is sunk in the wall as usual, not in front of the wall as in stoves, for which the conditions are different, as we saw just now. It is a common mistake with those who want to have as small a fire as possible to put in a lump of fire-brick at the back to diminish the depth of the grate, and also sloping upwards; which is doubly wrong; first because a fire too shallow will not burn properly, i.e. not so well as the same quantity of coals in a square form, and secondly because a back sloping upwards sends the heat towards the top of the room, or just where it ought not to go. That has at last begun to be understood and some later brick backs are actually made sloping forward, which is right if the grate is also set high, and not low, as usual.

The fact is that nearly all grates now are set too low. Some people once got it into their heads that the best way to warm the floor was to put the fire on the hearth, or as near it as possible, which is just the way not to warm the floor, because no heat then can radiate on to the floor. It wastes also an immense quantity of heat by sending it below the hearth; and such a fire is particularly disagreeable to the eyes; and it is the worst place that could be invented for ventilating the

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Fire-places and Brick backs.

room: there is a very sensible difference in the quality of the air of a room with a low chimney front and a high one. Another effect of low grates is that a fender shuts off the heat altogether from all the floor near it. Yet this stupid thing was done over and over again till people found out at last that those grates upon hot bars were intolerable. But still nearly every grate is too low. I am sure that there ought to be at least 7′′ clear below the bars, and 9′′ are better. Moreover you must remember that the top of the fire-place opening must be raised with the bars, or the opening will be too small and the fire will blow up the chimney as when a temporary blower' is put on.

6

Two other wonderful bits of coal-saving science may be noticed. One is the discovery, which was written about in all the newspapers a few years ago, that a close instead of an open bottom to the grate burnt less coal. The revealer of this great secret might as well have gone a step farther and announced that a close front too would burn still less; and finally that admitting no air at all would save all the coals. Besides all this, imperfect or very slow combustion generates carbonic oxide, which is unwholesome, and is apt to spread into the room for want of heat enough to carry it up the chimney so at least it is said in chemical books, for I do not profess to vouch for that myself, though the utter badness of such stifled fires I do vouch for, and of low ones. Another fashionable bit of science that flourished for a winter or two was that lumps of chalk would do as well as lumps of coal, whereas they do no more than the older invention of fire clay balls, which increase the red hot surface in a tolerably large fire and so make it look bigger and perhaps radiate a little more in the room, but they kill a small fire; and the

idea of their actually increasing the heat is absurd. I doubt whether they even radiate any more than a brick back and sides. The sides should of course make an obtuse angle with the back, unless back and sides together are a segment of a circle, which is probably the best shape of all.

Hearths of encaustic tiles with low marble fenders are a real modern improvement, or revival. They nearly always look well, and are less trouble to clean than a quantity of iron and brass work-in fact hardly any. Many people fancy that white or statuary marble is the hardest of any, whereas it is about the softest, and therefore the least fit for those fenders for feet to tread and fire-irons to fall on. Sienna (yellow) marble is very hard, if not the hardest. White marble must be kept quite clear of grease and cleaned with soap and water, but most of the other marbles are improved by a little greasing. I learn this from Mr. Boucneau of Warren Street, Fitzroy Square, whose stock of chimney pieces I advise anyone who wants such things at any rate to look at. The architectural monstrosities in that line that one sometimes sees are prodigious, especially in so-called Gothic houses of much pretension.

Ventilation is generally treated of with warming. I have already said almost as much about it as is necessary. Some ladies, especially in London, are so afraid of 'blacks' that they prefer the infinitely more noxious invisible dirt of bad air, and hardly ever let their windows be opened. The blacks may be kept out to a great extent by wire-gauze blinds of the old-fashioned kind, or by muslin stretched on a frame; both of which are in every way better than those absurd bits of wicker work which have lately come into fashion and do absolutely nothing that a blind is wanted for. Moreover

people ought to know that a few minutes' draught right through a room, especially a dining room after meals, with both door and a window well open, will do more to purify the air and will let in much less dirt than a bit of window open for a much longer time. The best way of ventilating halls and schools which require constant fresh air while they are filled with people, when open windows will not be tolerated on account of either cold weather or noise, is by divided large tubes through the roof, depending on a principle which is usually illustrated thus :-If you put a short lighted candle down into a large bottle it will soon go out; but if you divide the neck of the bottle by a card, or by putting a smaller tube into it, the candle will burn, because one division makes itself a down-draught and the other an up-draught. To make the circular spaces equal, the diameter of the inner tube must be not half, but 7 or rather more than of the outer one. If you make two such concentric ventilating tubes of considerable length, they have the further advantage that the downdraught gets a little warmed by contact with the tube of the up-draught. The only objection to them is that these chimneys generally look very ugly in the roof; but they may he enclosed in square fabrics with louvres like bell cotes, which do not look inappropriate on schools and some other buildings, though they will not do for churches on account of their defacing the roof. Besides they can always have opening windows in the clerestory if there is one. Bedrooms with fire-places ought never to have the chimneys closed, and for that reason I would never allow a register stove in one.

Rooms without fire-places should have some constantly open hole or holes as high up in the room as possible, into the roof or the passage. Such holes are