CONSERVATORY. In horticulture, a glazed structure, in which exotic trees and shrubs are grown in a bed or floor of soil. Technically, it is distinguished from a greenhouse by the plants being planted in the free soil, and thus growing up from the floor, while in the greenhouse the , plants are grown in pots placed on shelves, or on a stage or series of shelves rising one above another. They are exclusively employed for the preservation of plants which are in a growing state during the winter. There are many forms of conservatories and greenhouses, including what are called propagating houses, or pits, cheap structures used by professional florists for growing plants and flowers for sale. These are made to face the south, when built as a lean-to to another building, or they may be made as shown in the cut below, separate, and about fourteen feet wide, when the roof slants both ways, the north slope being usually not more than half the length of the south slope. The propagating-bed is of brick, single width, and nine courses high; size, three feet by ten. Com mon slate is laid on the top, supported by brick, laid up for the purpose from the top of the flue. A space of half an inch may be left between the slates. On the side, a few openings should be left for ventilation, so arranged as to be closed at pleasure. Make a frame the size of the top of the bed, of plank, ten inches wide by one and a quarter thick; set this on the top of the bed, and run an iron through the center to prevent the sides from spreading. In this frame, and on
top of the slates, place three inches of pebbles about the size of hickory nuts; then one inch of fine gravel; then, filling the bed with fine sand, it is ready for use. Charcoal may be substituted for pebbles. The house should front south or southeast. The front glazing should be lower than the back; and may be within eighteen inches of the ground. An evaporator, or large pan of zinc or boiler-iron, should be placed upon the flue to render the air moist. Hanging shelves may be introduced if needed; they are very con venient for bringing plants near the glass. If it be heated by flues direct from the fire, they should be of brick, and run around the house, returning to the same end from which they started, or may be carried directly under the propagating bed. By such means a small house may serve a family and furnish all the plants and flowers during winter, and the females of the household will derive much pleasure in attend ing to it. When the house is only to be a small one, we should advise that it be a lean-to, com municating directly with the house,