walk (x), leading through the shrubbery and pleaure-ground to the botanic department and the house. All on the south side of the carriage road (y z) is pleasure-ground. The forcing-range (fig. 102. p. 514.) was begun and carried on at the same time with the open garden. Its consists of three vineries with fig trees on the back wall (5, 6, 7); two peachhouses with table trellises, and trees on the back wall (4, 8); and six pits or low houses (1, 2, 3, 9, 10, 11), for fruiting pines, and for forcing kidney beans, strawberries, grapes, and figs in pots, roses and flowering shrubs, and flowers generally. We refer to p. 515. for minor details. The old houses being removed, the foundations for the new ones, as well as for the border in front of the vineries and peach-houses, were cleared out to the depth of 5 ft., and to the width in the part to contain the vineries and peach-houses of 35 ft. measuring from the back part of the back wall. All the foundations, except that of the back wall, were begun by carrying up piers, and these were joined by arches, which being brought to a level formed a basis, on which to build the flues and all those parts which appear above ground. The entire bottom of the border, within and without the vineries and peach-houses, was formed to a smooth slope with an inclination from the back to the front of 2 ft. This slope was paved with bricks laid flat, and the joints were grouted with mortar; the object of this pavement being to prevent the descent of the roots into the subsoil. A drain was formed in front of the border, the bottom of which was made about 1 ft. deeper than the surface of this pavement. On the pavement was next laid 12 inches of brickbats over the whole of its surface, and from this stratum air-chimneys were carried up close under the back wall in the houses, and over the drain in front. Sections of these chimneys may be seen in the cross sections of the vineries and peach-houses (fig. 102. E F G); and the surface gratings which cover them are indicated in the ground plan, along the edge of the garden walk in front of the border, and along the bottom of the back wall in the houses. These chimneys are 18 inches square in the inside, and covered with iron gratings; the use of them is to admit air to the porous stratum under the soil of the border; or, in case it should become necessary at any time, water or liquid manure might be poured down, and, by stopping the drain, it would rise in the rubble stratum and through the soil to any required height. It is evident, that by such an arrangement, the gardener has as completely the management of the roots of all his trees, as if they were in pots or boxes. It is a very common thing, in breaking up the foundations and borders of old vineries, to find the soil sodden, or soured, and the roots rotten, owing to an excess of moisture being joined with rich nutritious matter without air or drainage; but where air is admitted to circulate through a porous stratum, as in these forcing-houses, the soddening of the soil and the rotting of the roots cannot take place. We, therefore, consider this excellent contrivance deserving of adoption in all vineries and peach-houses, and, if it were not for the expense of it, in all fruit-tree borders and even in open orchards. The soil for the borders was prepared by collecting the turf or surface of an old pasture meadow of hazel loam, and laying it up in small ridges 2 ft. broad at bottom, and 3 ft. high, there to be summer fallowed, or operated upon by the sun's rays and alternate rains from May till September. During this period it was three or four times turned, but not broken into pieces. It has been found that the treatment of soil in this way during one summer is, for all horticultural purposes, worth several winters. While this preparation was going forward, about 30 tons of ground bones were laid in ridges covered with 6 inches of soil, to undergo that degree of fermentation which is found necessary before they can be applied with safety as a garden manure. They were not turned, but remained all summer covered with a layer of soil. A large quantity of horse and cow dung from London was fermented during the summer, in a dunghill about 3 ft. deep; it was watered when it appeared to be getting dry, and it was turned over four or five times. An immense quantity of leaves in a rotten state were collected from under the trees in the pleasure-ground; these were not fermented, because they were the accumulations of many years, and in consequence were, for the greater part, decomposed. The month of September being fortunately dry, the whole of these materials were then first mixed together and laid in ridges; the soil for the peaches being considerably (at least two thirds) less manured than that for the vines. This compost being all ready to be wheeled into its place, the stratum of rubbish was first covered with 6 inches of litter, haulm of beans or asparagus, clippings of hedges, summer prunings, &c. The weather being still dry, the whole was wheeled in, and thus the border was formed. It is to be observed, that during none of the turnings was the soil much broken or reduced to a fine state, or the turfy pieces and roots taken out; a matter which deserves to be particularly remarked, because many amateurs and in experienced young gardeners think that by sifting soil of its stones and roots they do a great deal for the plants, whereas in most cases they are merely bestowing on it a greater capability of becoming solid and sodden, than it would otherwise possess. Immediately after the border was filled with soil, from 6 to 8 inches of lime rubbish, that is, rubbish from old buildings, were laid over the whole of it; and during the ensuing winter the entire soil of the border, down to the stratum of litter, was turned twice and the lime rubbish thoroughly mixed with it. In the March following the trees were planted. The peaches and nectarines were chiefly full-grown trees, taken from the open walls, of approved sorts, which had already fruited there. They bore fruit the same season (1827), and ripened their wood well. The vines were plants of one year's growth, partly raised on the premises from eyes; they produced shoots from 20 to 30 ft. long, which in autumn were shortened according to their length and strength. The fig trees planted on the back walls of the vineries were full grown trees taken from the walls; they were planted in a border 3 ft. wide, and the roots kept separate from the vine border by a brick wall 41⁄2 in. wide, carried up from the bottom pavement. The soil consisted of lime and brick rubbish, with about one third of loam, without manure. They produced fruit the first year, and two good crops a year ever since. In February and March, 1828, the peaches and vines were forced moderately, both produced abundance of wood, the peaches as strong as could be desired, and the vines shoots from 20 to 40 ft. long, the wood, in some cases, 4 in. in circumference, with numerous bunches of fruit, all of which were taken off, except enough to prove the sorts. In the autumn of this year (1828), the roofs of the vineries, and the table and back trellises of the peach-houses, were covered with excellent fruit-bearing wood; in November, fires were put to the peach-houses: the weather during the three succeeding months was dark and moist, and altogether very unfavourable for forcing, but, notwithstanding, ripe peaches were gathered early in the following May, weighing from 7 to 9 ounces each, which were regularly and successfully forwarded to His Excellency's establishment, Phoenix Park, Dublin. The vines were begun to be forced on the 17th of November. From the length and strength of the shoots, it seemed doubtful whether they would break regularly at every bud; but by bending the shoots in a serpentine form (fig. 100.), and retaining them about a month in that position, every bud, from the lower part of the shoot to the summit, pushed out leaves and showed fruit. As soon as this was effected, the shoots were restored to their straight position; most of them showed two or three bunches on every young shoot, and 100 some four or five bunches; indeed, such was the abundance of the blossom, that some shoots showed 96 bunches. In the three houses, one of 40 ft. and two of 32 ft. long, and about 19 ft. wide, 1140 bunches were cut off in a green state in order not to weaken the plants. In this, the second year of their growth, between 300 and 400 bunches were brought to perfection and sent to Phoenix Park; and be it remarked that the first bunches were cut on the 19th of April, at a time when they were worth in London a guinea and a half per lb. The berries of some of the muscats measured 34 inches in circumference. The whole crop was cleared off by the end of June: the roof-sashes have since that time been removed, and the plants are now fully exposed to the weather, with their wood fully ripe, and the leaves dropping off. With respect to the six low houses for fruiting pines, forcing a variety of articles, and growing cucumbers, we can state from our own observation, and we know it to be generally acknowledged by the profession about London, that nothing ever surpassed the excellence of their produce. Last year, the family being in England, strawberries in abundance, kidneybeans, and forced flowers of extraordinary luxuriance were produced in April, May, and June, and pine-apples of as large a size as had ever been seen at so early a period of the season. Cucumbers, some of them 2 ft. long, were gathered in the early part of the spring of the present year; and ripe grapes from plants in pots were cut on the 15th of February. It may now be necessary to take some notice of the materials of which these forcing-houses, and also the range of pits behind them, are constructed. The pits are, for the greater part, of timber, with brick walls and smoke-flues. The roofs, ends, divisions, and trellises of the forcing-range, with the exception of three of the pits at the east end, are of metal; the bars of the sashes being of copper, and their styles and rails and the rafters and every thing else of cast and wrought iron. The floor of the path in the central range is also of cast-iron grating, supported on brick piers, which has the advantage over flag-stones of admitting the sun and air to the soil below. The whole length of this path is on one level, and when the doors of the five divisions of these houses are open, the view from one end through them surpasses any thing of the kind we have hitherto seen. All the houses are heated by fire-flues, built of brick and covered with tiles, each tile containing a hollow panel in its upper surface, for the purpose of holding water for evaporation. The direction of these flues in the area of the houses, and in the back wall, will be seen in the plans and sections in p. 514.; and though their success is very perfect, we consider it unnecessary to enter into the details of their construction, believing that in erecting similar ranges of forcing-houses in future, the mode of heating by hot water (as at the Duke of Bedford's, but on Weekes's principle, p. 544.) will be substituted. The mode of heating by hot water had not been sufficiently brought into notice, when Mr. Forrest formed the plan of this range, to justify its adoption. The low pits behind the range are covered at nights during the forcing season by wooden shutters; but no covering of straw mats, or of any other material, is applied at any time, for the purpose of retaining the heat, to the roofs of the forcing-range. The pine-pits in the range and the forcing-pits may be shaded in the daytime by letting down rolls of canvass, which cover the roof from end to end. The construction of these shades, invented by Mr. Forrest, deserves particular attention, not only because they are applicable to hot-houses, pits, and hot-beds of every description, but because they may be rendered available in the covering of fruit |