dry, or promotes this effect by moderate fires in the furnaces. Sometimes by increasing the heat within, and at others, by suitable applications of fire externally, he converts the whole into one entire mass of bricks. By occasional closing or opening of the furnaces at top, or any of the other apertures, in various parts, the intelligent operator will easily understand how to regulate the progress, communication, and effect of the heat, that the conversion into brick may be uniform through the entire mass.
5. The dimensions of the furnaces, the positions and relative distances of the pipes of communication and lateral apertures, and the thickness of the layers of the prepared material, are each susceptible of great variations, according to the nature of this preparation, the activity of the fuel, the proposed solidity or figure of the work, &c.
6. He then forms the remaining parts of the wall, or edifice, by applying additional portions of the prepared material in contact with that already baked; while he also avails himself of proper and suitable external and internal moulds, supports, frames, and other occasional contrivances, well known to builders, for sustaining works, or forming arches, or determining the figure and positions of soft plastic substances.
7. The ground-floor is likewise formed of the prepared material, leaving hollow spaces between the supports beneath, for making fires, ventilated by side apertures, which are provided with numerous holes. When the floor is of considerable thickness, it will require the construction of furnaces, in every respect similar to those before described.
8. The first above the ground floor is made upon suitable temporary framing, in such a manner that the upper surface shall be plane, and the lower concave, so that it may, when baked, support itself, upon the principle of a low arch.
9, and 10. The patentee constructs, bakes, or burns other floors above the first, and also the roof, &c. he closes the apertures, fills up the furnaces, amends the deficiencies, adorns the walls, floors, ceilings, or other parts, with his prepared material, according to the taste and direction of the proprietor.
Various plans have lately been devised for securing buildings, and ships, against fire. We shall, however, mention only that of David Hartley, Esq. who, in April, 1773, obtained a patent for his invention of applying plates of metal and wire, varnished or unvarnished, to the several parts of buildings of ships, so as to prevent the access of fire, and the current of air; securing the several joints by doubling in, over-lapping, soldering, rivetting, or in any other manner closing them up; nailing, screwing, sewing, or otherwise fastening, the said plates of metal in, to, and about, the several parts of buildings, and ships, as the case may require.—Convinced that this method would be too expensive for common buildings, and that it does not afford sufficient security against violent flames, when the contiguous buildings are actually burning, we shall suggest other, and more effectual means of protection, under the article Fire.
BULB, in botany, a kind of large subterraneous bud, though sometimes appearing above ground, upon
