This building being furnished with flues, &c. may be used as a Green-house at discretion, by introducing stages instead of beds, and in that case the glass-roof may be permanently fixed.

Work to be done in the Green-house.

In mild days, when the weather, externally, is moderate and calm, let the windows be opened a little for the admission of fresh air about ten or eleven o'clock; and about two or three in the afternoon let them be shut close again. But the time of opening, and the time they should be kept so, must always be determined by the weather; for there are many changes, sometimes in a few hours, at this season. The upper lights may be let down a few inches for the admission of fresh air, as well as to let out the foul air of the house, even when the under lights cannot be raised with safety.

In frosty weather, the windows must be kept constantly close; and, if very severe, let the window shutters be shut every night, and even occasionally in the day time, when the frost is extremely rigorous, and no sun; or, in default of shutters, on this occasion, let garden-mats be nailed up against all the windows, or strong canvass hung on rollers, be let down before them, and remove the small or more tender plants in front, as far from danger as possible.

Keep the plants perfectly clear from decayed leaves, and as clean as possible from any considerable foulness; and every part of the house clean and free from litter of fallen leaves, &c.; all which is essential at this time for the prosperity of the plants in general.

When the weather is foggy, or very wet, it will be proper to keep the windows and door close.

Water must be given to such plants as you see require it; but let that be given in very moderate quantities, and always, if possible, take the opportunity of a mild day, and if sunny, the better: in the forenoon, from eleven to twelve or one o'clock, is the proper time of the day for watering at this season; and generally prefer soft water for this occasion.

But very little water must be given at this season of the year to any of the aloes, sedums, or any other of the succulent plants.

Let it likewise be observed, that such of the woody exotics, as oranges, myrtles, geraniums, &c. as you shall see necessary to water, should have but a very moderate quantity given them at any one time.

In such green-houses, where there is the convenience of flues, for occasional fire-heat in very rigorous weather, you should, in time of continued severe frost, make moderate fires in an evening and morning, just sufficient to warm the inclosed air enough to resist the frost; also in very foggy or moist weather, may make a very moderate fire to expel the damp, which often proves pernicious to some of the more delicate exotics of this department.

THE HOT-HOUSE.

HOT-HOUSES, or STOVES, are buildings erected for preserving such tender exotic plants, natives of the warmer and hottest regions, as will not live in the respective countries where they are introduced, without artificial warmth in winter.

Though there are great varieties of these stoves, yet they are reducible to two; the dry stove and the bark stove. They are both, comparatively, of modern invention; the first, as far as I can learn, not having been in use more than one hundred and twentyone years, being introduced by Mr. Watts, gardener at the apothecaries garden at Chelsea, near London, who, in the year 1684, contrived flues under his green-house; the latter being much posterior, not having been brought into repute till about the year 1720, when Mr. Le Cour, of Leyden, in Holland, discovered its utility for the propagation of the pine-apple, which had never before been brought to good perfection in Europe. Before the use of bark-beds was introduced, all stoves or hot-houses were worked by fire-heat only; hence they obtained the name of stoves.

These stove departments are generally constructed in an oblong manner, ranging in a straight line east and west, with the glass front and roof fully exposed to the south sun; and in dimensions may be from fifteen or twenty, to fifty or a hundred feet long, by twelve. or fourteen, to sixteen feet wide in the clear, and commonly from ten to fourteen feet high in the back wall, by five or six in front, including the wall and upright glasses together, and furnished with flues round the inside of the front and end walls, and in several returns in the back wall for fires; and with the whole roof overhead, sloping to the south, entirely of glass-work, supported on proper

cross-bearers.

Steves of much more capacious dimensions, are frequently erected by persons of fortune and curiosity, for the cultivation of the taller-growing kinds of exotics, which shall be taken due notice of, after the less expensive and more generally used kinds are described.

The Bark-Stove,

The Bark-Stove is so called, as being furnished with an internal pit for a bark-bed, as well as with flues for fire-heat, and is the most universally used, as being the most eligible for the general culture of all kinds of the tenderest exotics, as well as for forcing several sorts of hardy plants, flowers and fruits to early perfection: the bark-bed being designed to effect a constant moderate moist heat all the year round, and the flues used occasionally for fire-heat in winter, or during cold weather, to produce such an additional warmth in the internal air, as may be requisite at that season; the

bark-bed being formed, as hereafter directed, is productive of an uniform moderate growing heat, of long duration, peculiarly adapted for the reception and growth of the most tender exotics, which require to be kept constantly plunged in their pots in it; such as pine-apple, &c. in order to enjoy the benefit of that durable, moist bottom heat about their roots, peculiar to bark-beds only, whose heat also evaporates and warms the air of the stove at all times, that even the plants on the surrounding shelves are comforted by its influence; so that with the aid of fire-heat in winter, regulated by a well graduated botanical thermometer, placed constantly in the stove distant from the fire place, and as much in the shade as possible, there are hardly any exotics from the hottest regions of the world, either woody, herbaceous, or succulent, but may be cultivated in it, by placing them in such different situations, as their natures may require.

In the arrangement of the plants in this stove, some require the bark-bed, others succeed in any part of the house, and others, such as the succulents, require the driest situation near the flues: many of the more tender, herbaceous, and shrubby plants, natives of the hottest countries, generally succeeded best when plunged in the bark bed, though many sorts, both herbaceous and woody, thrive tolerably well in any part of the Bark Stove.

I shall now proceed to give a minutia of its general structure, upon the most improved plan, the more especially as many persons who may be desirous of erecting such, may probably not be able to procure workmen capable of constructing it, without minute and particular directions.

Having determined on the size, as to length, width, &c. proceed to lay the foundation of the walls, allowing due thickness for the erection of the surrounding inside flues on the foundation wall, with an allowance for their being detached therefrom about two or three inches.

Then set off the back or north wall, at least two bricks or eighteen inches thick, and the front and end walls about thirteen, carrying up the back wall from ten to fourteen feet high, in proportion to the width of the house; but those of the front and ends, from two to three feet, as the circumstances hereafter noticed may require, upon which to erect the upright timber framing for the perpendicular lights; previously observing, in carrying up the walls, to allot a proper space for a door-way, at one or both ends towards the back part; setting out also the furnace or fire-place, in the bottom foundation, towards one end of the back wall behind, formed also of brick work, and made so as to communicate with the lowest flue within, the inside top of the furnace being about a foot lower than said flue, the better to promote the draught of heat and smoke; though, if the stove be more than about thirty-five feet long, a fireplace near each end will be necessary; or, if more convenient, they may both be in the middle of the back wall, each communicating with a separate range of flues; in either case you may form them wholly on the outside, or part outside, and part running through the wall.

This furnace is to be made large or small according to the kind of fuel intended to be used and the number of returns of the flues inside; for when there are but few returns, a greater quantity of fire will be necessary to keep a sufficient heat. If the returns are frequent, and wood is to be the fuel, the furnace is to be made only three feet deep, to receive wood two and a half feet long or better; but if the flues run only once round, with no returns, the depth must be five feet to receive four feet wood, especially if the house be large; in either case the furnace is to be made eighteen inches wide at bottom, the sides sloping outward to the height of twenty inches, where it is to be twenty-two inches wide, covered from thence by an arch, the top of which is to be two feet from the grate, which is to be made of iron-bars, and one half of the depth of the furnace; the brick for the furnace should be laid in good well-worked brick-clay (not in mortar), which, when burned by the fire, will cement so as to become a solid mass; this must have an iron-barred grate one half of the depth of the furnace, as before observed, the remainder of the depth to be made solid with brick; having an ashhole underneath, with a close-shutting door to it. The furnace must also have an iron door placed in an iron frame, which door must be furnished, near the lower part, with another small door, for the admission of air to the fires, both having latches, so as to shut close occasionally; observing that this door is not to be wider than what is necessary for the admission of the fire-wood. Having both your ash-hole and furnace thus provided with close-shutting doors, you may manage your fires to great advantage, by closing them up occasionally from too great a current of air, especially when burned clear, which would carry off the heat through the flues too rapidly. If you intend to burn stone-coal, the furnace need not be so large, but the grate must run the whole depth.

Having finished the furnace, proceed to carry up the walls, observing particularly, to leave a scarcement a foot wide in both end walls; immediately opposite, where the back-wall flues are to be erected, from the level of the lowest flue to the top of the highest, by which means you can open the ends of the flues and clean them, when necessary, either by running in scrapers on the ends of long poles, or hauling any kind of small brush-wood through them, by means of a line from one end to the other; these scarcements may either be made up with brick from time to time, or with sashes and shutters, which will be more convenient. Whenever there are returned flues, one above the other, similar contrivances will be found useful; but where there is only one running flue, a top tile may be taken off at convenient distances, by which means it can be cleaned. When the walls are finished, then begin to erect the flues along the inside walls; but, as before mentioned, it would be adviseable to have them detached therefrom two or three inches, that, by being thus apart, the whole heat may arise from both sides of the said flues, which will afford an additional advantage, in more effectually diffusing the whole heat internally in the house; much of which would be lost in the back wall were the flues attached to it: the first range may be carried along the front and both ends, dipping under

the end door-ways and rising the other side; if there is no return flue to be in front, which is not necessary in a house of moderate dimensions, let this flue be carried so that the covering tiles and plaister may be within three inches of the level of the front and end walls, upon which a board may be supported with bricks, to be brought on an exact level with the front wall, for the convenience of placing thereon a number of pots of strawberries, for forcing, or any other small plants; and, moreover, the flue being carried near the glasses, the heat will be particularly efficacious in repelling the cold external air, frost, damps, &c. and also in distributing the heat more equally to all parts of the house: for the several returns in the back wall, will counterbalance the strong heat discharged by this first range where most wanted.

The first range being continued round the front and ends, must then be carried along the back wall in four or six returns, which will be sufficient to expend all the heat before its discharge into the chimney, which must be carried up immediately from the end of the uppermost or last flue, either in or outside of the back wall, so as not to appear in the inside of the house, and particularly in the opposite end to the fire-place.

The under range of flues, immediately communicating with the fire, ought to be four bricks on edge deep, that they may not be too soon stopped with the soot, and all the flues eight inches in the clear, and covered with broad tiles, the several returns may be made three bricks on edge deep; and, in the beginning of the first bottom flue, you may have a sliding iron regulator, to use occasionally in admitting more or less heat, as it may seem necessary; being very careful, as you proceed, that the brick-work of each flue be carefully jointed with the best mortar for that purpose, and well pointed within, that no smoke can get out, having each return closely covered with broad tiles, well bedded and jointed with mortar, covering the uppermost flues also with broad thick tiles the whole width, all very closely laid and joined as above, and the said uppermost or last range of flues, to terminate, as before observed, in a vent or chimney at one end of the back wall; or, if two separate sets of flues, a chimney at each end, in which you may contrive an iron slider, near its communication with the last flue, to confine the heat more or less on particular occasions, or to prevent its passing off too quickly, or becoming of too weakly a degree.

In very wide stoves, flues are continued immediately round the bark-pit, within an inch or two of the wall, to form a vacancy for the heat to come up more freely, and also to prevent its drying the tan of the bark-bed too much, which flues may be used occasionally or generally, by the assistance of a sliding iron regulator, to admit or exclude the heat less or more as it may appear expedient.

You should be very careful that neither the fire-place, nor flues, be carried too near any part of the wood-work, lest it should take fire.

Proceed now to set out the cavity for the bark-pit, first allowing a space of eighteen inches, or rather two feet wide round the front and both ends, and also a walk of two feet, or two and a half, along