To prevent the fire burning too furiously, the mouths of the flues are stopped with old bricks, and the outside of the whole clamp plastered with clay; and against any side particularly exposed to the rain, etc. screens are laid, made of reeds worked into frames about six feet high, and of a width to admit of being moved about with ease. This is the mode of manufacturing the ordinary descriptions of bricks; but the superior sort, termed washed malms or marls, are tempered with greater care and attention. For this purpose a circular recess is built about four feet high, and from ten to twelve feet diameter, paved at bottom, with a horse wheel placed in its centre, from which a beam extends to the outside for the horse to turn it by. The earth is then raised to a level with the top of the recess, and forms a platform for the horse to walk upon. Contiguous to the recess a well is formed for supplying the recess with water, which is raised by a pump worked by the horse wheel. A harrow made to fit the interior of the recess, thick set with long iron teeth, and well loaded, is chained to the beam of the wheel to which the horse is harnessed.

The soil prepared in the heap in the usual manner is brought in barrows, and distributed regularly round the recess, and a quantity of chalk is added, and a certain portion of water; and the horse being set in motion, drags the harrow, which forces its way into the soil, admits the water into it, and by tearing and separating the particles, not only mixes the ingredients, but also affords an opportunity for stones and other heavy matters to fall to the bottom. Fresh clay, chalk, and water, continue to be added until the recess is full. On one side of the recess, and as near, it as possible, several hollow square pits are prepared about 18 inches or 2 feet deep. The soil, reduced to a kind of liquid paste, is discharged from the recess by a sluice, and conveyed by wooden troughs to this pit. In these pits the fluid soil diffuses itself, settling of an equal thickness, and remains until wanted for use, the superfluous moisture being drained or evaporated away by exposure to the atmosphere. The remainder of the process is the same as for the common sort of bricks. In the country, bricks are always burned in kilns, whereby much waste is prevented, less fuel is consumed, and the bricks are more expeditiously burned.

A kiln is usually 13 feet long by 10 feet 6 inches wide, about 12 feet in height, and will burn 20,000 bricks at a time. The walls are about 14 inches square, and incline inwards towards the top. 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 gradually; this is continued till the bricks are pretty dry, which is known by the smoke turning from a darkish to a transparent colour. The burning then takes place, and is effected by putting in brush-wood, furze, heath, faggots, etc.; but before these are put in, the mouths of the kiln are 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 faggot at a time; the fire is then made up, and continued till the arches assume a whitish appearance, and the flames appear through the top of the kiln, upon which the fire is slackened, and the kiln cooled by degrees. This process is continued, alternately heating and slackening, till the bricks are thoroughly burned, which is usually in the space of forty-eight hours.

Many attempts have been made of late years to supersede, by the aid of machinery, a portion of the manual labour now employed in the manufacture of bricks; and although only the most recent of the machines invented for this purpose have been found to answer in practice, several of them are worthy of notice. The engraving on the following page represents Messrs. Choice and Gibson's brickmaking machine, a a a a is an upright frame, with cross beams at top and bottom; b c are two vertical shafts, carrying two horizontal spur wheels d and e, the teeth of which take into one another; these are put in motion by the horse shaft f, or any other convenient power. Near the bottom of the shaft b is fixed a large cast iron collar g, having three deep mortices; into each of these the end of an iron arm h is fitted, with a bolt passing through them to form a centre, as in a hinge joint. To the other extremity of each of the arms h is firmly fixed, by screw-bolts, a cast-iron mould box i, having three divisions for three bricks, in which work three stocks or false bottoms, having upright bolts passing through holes in the top.

By the revolution of the shaft, these mould boxes, with their arms, are successively carried up and over the risers k k k, which form circular curves in the plan, and appear so in the perspective, but are in reality inclined planes. At f, near the bottom of the shaft, is a small bevelled wheel, which actuates a pinion fixed on the spindle of the drum wheel m that passes under the floor of the machine; an endless strap passing round the drum m, and another placed at the required distance, continually carries the bricks forward to their destination as fast as they are made, and deposited upon it. o is a crank or lever, attached by a joint to the framing, as shown, at the upper end of which is fixed a roller; by the revolution of the wheel above the three circular bars or cams r r r, attached to the wheel, successively act upon the roller, and depress the crank o, which first raises the rod and weight q, and afterwards- as soon as the crank is relieved of the pressure, allows it to drop and strike the mould boxes, by which the bricks are discharged out of them, s is a box of cast iron, containing water, into which the mould boxes dip; t is a cushion, upon which they next fall in succession, by which the superfluous water is taken off; and j is a box of dry sand, into which the mould boxes afterwards fall, their surfaces becoming in consequence slightly coated with sand previous to becoming charged with clay.