CONSERVATORY (from the Latin. conserro, to keep) may lie defined generally as a place for preserving anything in it state desired, as from loss, decay or injury ; in this sense, granaries for keeping corn, ice-houses, may be called conservatories.
In gardening. the word conservatory is so frequently eon fmnaded with GREEN-IlorsE, and the terms are applied with so little precision to buildings used fin- preserving plants in an artificial climate, that it is difficult to define what is prop erly a conservatory. " The term," says a writer in the • Penny C yeloprn1;«, " which, as its meaning shows, was originally intended for buildings in which plants were pre during winter. has come to be used, firstly, finr glass houses in which plants are cultivated by growing then in the open border, and subsequently for all such glazed build ings whatsoever. A conservatory, properly so called, is a brick building heated by artificial means, having its whole southern part closed by large glazed sashes, which may be opened or shut at pleasure. Its floor is generally of stone, and a part of it is occupied by a stage on which plants in pots call be placed. Such a conservatory was intended to preserve during the winter, orange-trees, myrtles, American aloes, and similar plants, which during the summer will flourish in the open air, but which require during the winter to be protected." The modern or popular meaning of the word, is now almost the opposite of the original one, and a conservatory is said to differ from a green-house principally in this, that in the latter the plants and trees stand in pots, placed upon stages; and in the former are regularly planted in beds of the finest composts, on being removed from the green-house, and taken out of the tubs or pots. By introducing stages, instead of beds, however, one may serve for the other.
The construction of a conservatory is similar to that of a green-house; but it should be more spacious, elevated, and finished in a superior style. The sides, ends, and roofs should he of glass, in order to admit light freelv, and to protect the plants. It should likewise lie so situated as to be quite dry, receiving as much of the heat of the sun as possible during the day, and provided with lbws to communicate heat when found necessary, and valves and other conveniences for the introduction of fresh air, when required, for the pur pose of ventilation. In summer-time, the glass roofs are sometimes taken oll; and the plants exposed to the open air, but on the approach of the autumnal frosts, they must be restored.
There is much diversity of opinion amongst practical men as to the comparative merits of wood and iron in the con struction of conservatories. Mr. J. Thompson, a man of great experience, in his " Practical Treatise," gives the pre ference to wood, although acknowledging the advantages of iron in lightness of appearance. " Any persons," he observes, " having a knowledge of the expansion and contraction of metals, may' form some idea of the expansion of a large iron roof on a hot day during the months of July and August, and of the contraction on a severe frosty night ; so great have I witnessed the action of the sun's rays in expanding the iron rafters and lights upon a hot day, that it has required two or three men to draw down the sliding-lights; and in an equal proportion have I seen the contraction during the intensity of winter, so much so, that large apertures have appeared between the rafters and lights, which admitted the external air to such an extent, that it required the strength of two fires, and the flues heated to the greatest excess, before the house could be raised three degrees of heat, and this in a house of not very large dimensions." This gentleman also objects
to the iron-roofed houses, that they require double the quan tity of fuel that is necessary in houses otherwise constructed. Notwithstanding some admitted disadvantages, the great convenience of iron, the readiness with which it is manufac tured, and the extreme lightness and elegance of its appear ance. will always give it a great advantage. Some of the most imigniticent conservatories in this country, have been constructed of iron, amongst which we may especially notice that in the Botanic Garden, Regent's Park.
This building was erected under the direction of Mr. Deeimus I'mrb n, and forms the half of the centre part of the proposed " Winter Garden," in which, when completed, the subscribers to these beautiful gardens will he able to enjoy the luxury of the parterre at all seasons of the year.
It is constructed of' iron, principally wrought, the pillars and glittering only being east. The water from the roof is conducted by the internal pillars, to large tanks under ground, from whence it is pumped up for the supply of the house. The building is heated by warm water conveyed through pipes arranged beneath the surface, in brick channels, having large outlets for the hot air, with air-ducts at intervals to create a current, and give increased action to the hot air in the drains. The boiler-house is beneath the ground, at some distance from the building.
The structure is ventilated by sliding-lights in the roof, acted on by a simple contrivance, which opens and shuts the whole simultaneously, and is glazed with sheet-glass in long lengths.
The whole building contains above eleven thousand super ficial feet. It was erected by Mr. Turner, of the Hammer smith Ironworks, Dublin, at a cost of about £6,000.
The conservatories at Sion House, the Duke of Northum berland's, Alton Towers, the Earl of Shrewsbury's, and the Duke of Devonshire's at Chatsworth, are on the most mag nificent scale, and are especially worthy the study of the young architect who may be called on for designs for a build ing of this description. Ile will also find much valuable practical information in Mr. .1. \V. Thompson's work on the Contruction /tr Stoves, and other horticultural Buildings." The conveniences which may be attached to conservatories, consist of retiring-rooms, seed-rooms, aviaries, &c. If there be no sheds behind, the walls should not be less than three bricks thick.