In the country bricks arc always burned in kilns, whereby much waste is prevented, less fuel consumed, and the bricks are more expeditiously burned. A kiln is usually thirteen feet long, by ten feet six inches wide, about twelve feet in height, and will burn :20,000 bricks at a time. The walls are about one foot two inches thick, and incline inward towards the top, so that the area of the upper part is not more than 11.1 square feet. The bricks are set on flat arches, having holes left between them resembling lattice-work. The bricks being set in the kiln, and covered with pieces of broken bricks or tiles, some wood is put in and kindled, to dry them gra dually ; this is continued till the bricks are pretty dry, which is known by the smoke turning from a darkish to a trans- parent colour. The burning then takes place, and is effected by putting in brushwood, furze, heath, fagots, &e., but before these are put in, the mouths of the kiln arc stopped with pieces of brick, called shinlog, piled one upon another, and closed over with wet brick earth. This shinlog is carried just high enough to leave room sufficient to thrust in a ingot at a time ; the tire is then made lip, and continued till the arches assume a whitish appearance. and the flames appear through the top of the kiln; upon which the tire is slackened, and the kiln cools by degrees. This process is continued, alter nately heating and slackening. till the bricks are thoroughly burned, which is generally in the space of forty-eight hours.
The practice of steeping bricks in water after they have been once burned, and then burning them again, renders them more than doubly durable.—Go/dhaam.
Many attempts have been made to introduce machinery in the practice of but with little :meccas, as is evi dent from the old practice continuing so general in use.
The most usual varieties of bricks consist of marls. storks, and place-bricks. but there is very little difference in the manutimeture. Ma•is are prepared and tempered with the greatest care; but the construction of the clamp for burning them is similar to that fur other bricks. though more caution is required not to overheat them, and to see that the tire burn equally and diffusively throughout the clamp or kiln. The finest marls, called are selected as cutting bricks, for arches of doorways, windows, and quoins; for which purpose they are rubbed to their proper dimensions and The next best, termed seconds, are used for principal fronts. The cleanly pale yellow colour of marls, added to their smooth texture and superior durability, give them a pre-eminenee above other sorts of bricks. are somewhat like the seconds, but of an inferior quality. some times called peckings, sandal, or are such as, from being outside in a kiln or clamp, have not been thoroughly burned, and are consequently soft, of a more uneven texture, and a red odour. There are also burrs, or such as front being too violently acted upon by the fire, have vitrified in the kiln, and sometimes several are found run together.
are made in the country, and burned in kilns. They owe their colour to the nature of the clay of which they are fia•ned, which is always used tolerably pure. The beat sort are used as cutting bricks, and are called red rubbe•s. in old buildings they are frequently to be seen, ground to a fine smooth surface, and set in putty, instead of mortar, as ornaments over arches, windows, doorways, &e. Though many very beautiful specimens of red brickwork are to be met with, yet these bricks can seldom be judiciously used for the front.walls of buildings. The colour is much too heavy, and in summer conveys an unpleasant idea of heat to the mind ; to which may be added, that as in the fronts of most buildings of any consequence, more or less of stone work is introduced, there is something harsh in the contrast between the red bricks and the cold colour of the stones ; and even where no stone is employed, there is always some wood used, which being painted white, by no means lessens the objection. Gray-stocks match so much better with the colour both of stone and paint. that they have obtained a universal preference in London and its immediate vicinity.
At liedgerly, a village near Windsor, red bricks, about one inch and a halt' thick, of a very firm texture, are made ; they will stand the greatest violence of fire, and are called bricks, and sometimes Bricks for paving are of the same dimensions with Windsor bricks, viz., nine inches long, four inches and a half broad, and one inch and a half thick. Besides these, there are what are called which are made of stronger clay. of a red colour. The largest are about twelve inches square, and one inch and a half thick ; the next size, though called ten-inch tiles, are about nine inches square, and one inch and a quarter thick. See TILES.
Besides the foregoing varieties, the following are worth notice, though some of them are not much in use : 1. The ordinary Paris brick is eight inches long, four inches broad, and two inches thick, French measure, which makes them rather larger than ours. 2. Buttress, or plaster bricks, made with a notch at one end, half the length of the brick ; used for binding work built with great. bricks. 3. Capping bricks, used for the purpose which their name denotes. 4. Great bricks, used in fence walls, are twelve inches long, six inches broad, and three thick. 5. Cogging bricks, for making the indented works under the capping of walls built with great bricks. 6. Compass bricks, of a circular form, for steyning wells. 7. Concave. or hollow bricks, made flat on one side, like an ordinary brick, and hollowed on the other side; used for drains and water-eourses. 8. Dutch, or Flemish bricks, used in paving yards, stables, &e., also for lining soap-boilers, cisterns, and vaults. 9. Feather-edged bricks, made of the same size with the ordinary statute bricks, but thinner on one edge than on the other ; they are used for pinning up brick panels in timber buildings.