The most common form and arrangement of the best greenhouses Beats By Dr Dre which are built against walls, is that of the annexed figure, and these answerevery purpose of cultivation. The arrangement of such a house is this: the roof is composed of two lights, and is supported by castiron uprights, a, placed under every second rafter, and the intermediate rafter is supported by means of a semicircular iron bar, which, Dr Dre Headphones springing fromthe upright bar on each side, passes close under it, Beats By Dre and indeed is screwed to it, by which means the whole roof is tied together, and scope afforded for the training of climbing plants to the bars. The stage, b, is in the middle of the house, allowing a footpath all round, and the heat is communicated by means of the flues c, which pass down the front and return along the back. Shelves are fixed against the back wall, d, for holding plants in a state of rest, that they may be kept dry, and a small shelf, e, is also placed in front, immediately under the bottom of the rafters, for the reception of small, young, or delicate plants, particularly during winter. Over the front flue is a trellistable, also for small plants, and such as require abundance of air and light.Many fantastic and badlyarranged greenhouses have been erected, and, as it would appear, for no other purpose than that of creating forms that imagination only can approve of, and to have a house different from all others, and too often contrary to both reason and good taste. Nicol, a gardenarchitect of some pretensions, appears to have understood the rationale of building greenhouses upon very judicious principles. He agrees with us that a house to stand detached from other buildings should be of glass on all sides. " It may be a circular, oval, hexagonal, octagonal, or with two straight sides, and circular ends, which is," he thinks, " the best form of any: the next best an octagon, whose sides are not equal, but with two opposite longer sides, and six shorter sides. In either of these lastmentioned forms, the stages and plants may," at least in his mind, " be more tastefully arranged than in any other. Granting either of these cases, the house should be about thirtysix or forty feet long, eighteen or twenty feet wide, and ten, or at most twelve, feet high, above a level line for its floor.