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sqarge is showered in; after this a third, and so on, until the length is made up of the proper speeific gravity.

The quantity of hops seldom exceeds 4lbs. to the quarter of malt. A little honey and a few coriander seeds, or other aromaties, will assist the flavour. After the boiling, the worts are cooled down as low as 50°, and even 45°. The fermentation is carried on for a fortnight or three weeks. As small a portion of yeast is used as possible, and this is sometimes added in two separate portions; and, to prevent the fermentation from becoming slack, the tun is stirred up or roused twice a day, morning and evening, if necessary. When the fermentation has slackened, the ale is cleansed, or the top barm might re-enter the body of the liquor, and it would become yenst-bitten. When the ale is cleansed, the head, which has not been disturbed for some days, is allowed to float on the surface till the whole of the then pure ale is drawn off into casks. After this cleansing there is little or no yeast given off, as nearly the whole of the fermentation has been completed in the tun. The strength of the best Scoteh ale varies from 32 to 44 lbs. to the barrel. The ale soon becomes fine, and is seldom racked for the home market.1

Among the multitnde of recipes for domestic brewmg, on a small scale, one of the best (we speak from the experience of several years) is that given by Mr. Donovan, in the work already quoted. The great objection to domestic brewing is often the expense of the apparatus; but this writer shows how cheaply this may be procured. A common porterbarrel forms the mash-tun, for which purpose one end is to be taken out, and converted into a false bottom by letting it rest on a hoop nailed round the lower part of the barrel. This false bottom is to be perforated with a vast number of gimlet-holes, and a cock or spigot of wood is to be fixed in one of the staves, between the real and the false bottom. Another porter-barrel, with one end taken out, will serve both as underback and fermcnting-tun, and it may be placed beucath the cock of the mash-tun, so as to receive the wort when it is drawn off. A tin-plate boiler, furnished with a cock at the bottom, for placing over a common firegrate, is recommended for heating the mash liquors; but we prefer to use the laundry copper, which is provided in every house. A brewing thermometer maybe used, but can be dispensed with, as the proper heats can be determined by the admixture of cold and boiling water.

15 gallons of boiling water arc to be thrown into the mash-tun, and 5 of cold water (60°). The temperature of the mixture would be 174°, but for the cooling influence of the wooden vessel, which, however, should be well scalded immediately before. The mash-water will be about 170°. 2-J- bushels of the best ground pale malt are to be quickly shaken in, whhc a second person continually stirs with a stick, and this mashing is to be continued for half an hour, the barrel being covered over all the time with a thick

tI) Booth: Knowledge.

'Treatise on Brewing," in the Library of Useful

cloth, except in the small space wherc the stick is inserted. The tun should then be left quiet for an hour, after which the cock may be opened a little. The first flow of wort should be received into a wooden bowl: if not clear, it should be gently poured back into the mash-tun; but as soon as it begins to flow clear, the cock may be opened to the full. The malt will have soaked up the greater portion of the water, but the few gallons which flow off ought to be a full, rich, clear wort. Just when the last portions have run off, 20 gallons of water, not quite boiling, are to be lightly let over the residual grains. The wort retained by the malt will thus be washed down, and the whole quantity now in the underback will amount to 23 gallons. This is to be baled into the copper, and boiled for 20 minutes with 3|lbs of the best mild hops, after which it is to be passed through a large sieve into the fermenting-ttm; and when it has cooled nearly to blood-heat ((J8°), about a quart of good yeast is to be mixed in, and the fermentation is to be continued until completed. In cold weather the tun while working must be kept near the fire, as on this small scale the wort does not maintain the temperature adapted for working. When the fermentation shows a decided tendency to go down, the liquor is to be racked off, and put into a cask, and closely bunged up. The ale will measure 20 gallons, and will be ready for use in about a fortnight.

BEET BETA. This important plant belongs to the natural order Chenopodiacca?, which also inclndes Spinach, Orach, Mercury, Goose-foot, &c. Beet, more commonly known by its German name of mangold wurzel, is now famous as affording a new source of sugar, capable of being produced in northern countries. Common Beet (Beta vulgaris) has been extensively and successfully cultivated for this manufacture, which was commenced in the time of Napoleon, to gratify his earnest desire of rendering France independent of England, and was carried on under his constant notice and patronage, so that it is said he prondly exhibited the first specimen of beet-root sugar as one of his greatest treasures. The mode of cultivation recommended by French nat uralists, and found successful in rearing the plants, was as follows:—A low situation should be chosen, in which extremes of drought and moisture do not occur. The soil (which should be a rich loam in which wheat has been grown,) must have three good ploughings, and immediately after the third, which should take place at the end of April or beginning of May, it must be brought smooth by the harrow, and laid out for planting. This is done in France by means of a rake, whose teeth are from 9 to 12 inches apart, and arc therefore fitted to make lines along the surface, showing the distance each row of plants is to be from the other. The rake is afterwards drawn in transverse lines across these, and the ground divided into squares, measured by the distance of the rake's teeth. Into each intersecting point of these linos, one capsule containing several seeds is inserted to the depth of an inch. When the young plants begin to spring up, and six or eight leaves arc formed, the ground should be weeded, and if necessary, the plants thinned. After this the crop advances so rapidly that the outspreading leaves soon cover the ground, and thus completely prevent the growth of any more weeds. There is therefore no more trouble with the ground till the time of gathering, an important circumstance for the cultivator, who is then busy with his corn harvest. The beet does not attain its full perfection till the month of October.

The best seed is that obtained from beet which has not been transplanted, and which has produced thin spindle-formed roots. Among the varieties which produce this kind of root, one has a pale red rind, and is internally quite white. This is a valuable variety to the manufacturer, yielding much sugar and an agreeably sweet syrup; others have a deeper red rind, and reddish circles or stripes within. These have a less agreeable syrup, retaining a taste of the root, which cannot be removed without expensive chemical processes. Other varieties are white on the outside and yellow within. These yield much crystallizable sugar, but arc not fit for moist or raw sugar on account of the disagreeable taste of the syrup.

Various experiments have been tried with beet, to ascertain the effect of light on the development of the saccharine principle, and it seems to be fully proved that as in the case of asparagus, endive, etc., fhe part protected from the light becomes sweet, while the other parts remain bitter, so with beet-root, the saccharine principle is greatest in those roots whicn arc the most effectually protected from the light. Thus the natural growth of these plants, by which the leaves form a thick and umbrageous covering to the whole of the ground, should by no means be interfered with, and the practice occasionally followed of removing all the large leaves, is one which must necessarily deprive the root of a portion of its most valuable properties. The only leaves which it is safe to remove arc those which have begun to droop or decay; but to pluck the large succulent leaves, however convenient they may be as food for cattle, is very unwise in those who grow beet for making sugar. For a description of the process by which the sugar is obtained from beet-root, see Sugar,

BELL. [See Casting.]

BELL-METAL. An alloy of copper and tin. "'See Bronze. Casting.]

BELLOWS and BLOWING MACHINES. The common bellows is a very ancient instrument for assisting the combustion of a fire, by injecting into it a larger portion of air than would be supplied without such aid. The first form of this machine resembles that of the lungs, and was doubtless suggested by the common practice of blowing the fire by means of the mouth. It consists of two flat boards of an oval or triangular shape, each furnished with a projecting handle, and between the boards two or more hoops arc bent to suit their figure. To the edges of the boards is nailed a piece of leather,

broad in the middle, so as partly to enfold the hoops, and narrow at the two ends, thus forming a sort of enclosed chamber, capable of being enlarged or contracted by raising the upper board while the lower one remains stationary. To the lower board is fastened a metal pipe, and a hole is also made in the centre of this board, which is covered on the inside with a leathern flap or valve opening inwards. On raising the upper board the enclosed air is of course rarefied, and air from without rushes in by lifting np the valve. Then on pressing down the top board, the air is compressed, and driven forward along the pipe with a velocity depending on the amount of force with which the two boards are pressed together. The blast is not continuous, but in puffs,1 an interval of time being required for the air to enter the bellows through the valve, the blowing interval being to the filling interval as the areas of the apertures. In the oldest smelting houses this irregular blast was remedied by employing two bellows which blew al ternately, the one blowing while the other was filling. To supersede the necessity of frequent repairs, they were made entirely of wood, except the pipe or twyere. This invention is ascribed by Bectmann to one Lewis Pfannenschmid, of Thuringia, who settled at Ostfeld, near Goslar, in 1621, where he excited the jealousy of the bellows-makers of the place by the superiority of his machines. It is stated, however, that bellows entirely of wood for smelting houses and for organs, were constructed at Nuremberg as early as 1550. Beckmann describes these machines in the following terms:—"The whole machine consists of two boxes placed the one upon the other, the uppermost of which can be moved up and down upon the lower one, in the same manner as the lid of a snuff box which has a hinge moves up and down when it is opened or shut, but the sides of the uppermost box are so broad as to contain the lowermost one between them, when it is raised to its utmost extent. Both boxes are bound together at the smallest end where the pipe is, by a strong iron bolt. It may be readily comprehended, that when both boxes fit each other exactly, and the upper one is raised over the under one, which is in a state of rest, the space contained by both will be increased; and consequently more air will rush in through the valve in the bottom of the lower one: and when the upper box is again forced down, this air will be expelled through the pipe. The only difficulty is to prevent the air which forces its way in from escaping anywhere else than through the pipe; for it is not to be expected that the boxes will fit each other so closely as to prevent entirely the air from making its way between them. This difficulty, however, is obviated by the following simple and ingenious method:—On the inner sides of the uppermost box

(1) A very convenient form of domestic bellows was introduced a few years ago, producing a constant blast. A vaned wheel was enclosed in a tinned-iron box communicating with a tube. The supply of air was obtained by means of holes in the side of the vessel, so that by turning a small multiplying wheel at the sidethe vane was set spinning, and, drawing the air in, projected it out a!oi:s the tube.

there are placed movable slips of wood, which by means of metal springs are pressed to the sides of the other box, and fill up the space between them. As these long slips of wood might not be sufficiently pliable to suffer themselves to be pressed close enough, and as, though planed perfectly straight at first, they would in time become warped in various directions, incisions arc made in them across through their whole length, at the distance of from 15 to 18 inches from each olher, so as to leave only a small space in their thickness, by which means they acquire sufficient pliability to be everywhere pressed close enough to the sides." These bellows are made of clean fir-wood without knots. They are represented in Fig. 117, in which A E B F is the upper chest. B r the line of hinges, H the handle, and p the blast pipe,

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which is sometimes furnished with a valve opening outwards, to prevent the burning coals from being sucked into the bellows when the upper box is drawn up. The lower box, with one of the valves v, is shown separately in Fig. 118. The slips of wood at the sides are apt to become damaged, but they can be easily repaired, and every 3 or 4 months the outer sides of the inner box and the bolt which keeps the boxes together must be smeared with oil.

These bellows are of very large size; they arc 16 feet long by 5 feet, and the circular end is also 5 feet. The rise is 3 or 3j feet, expelling at each stroke about 90 cubic feet of air, and making eight strokes per minute.

The great objection to bellows of this kind, is the want of a continuous blast. This was first remedied by the addition to the single bellows first described, of a third board of the same shape as the other two, and connected with the lower board by means of a piece of leather, thus making two exactly similar cavitics or chambers, separated by the lower board of the single bellows, which now becomes the middle board of the double bellows. Each of these two boards is furnished with a valve, and the blast-pipe is connected with the upper part of the middle board. The lower board is held down by a weight, and a weight is also placed on the top board, by which means the air is forced out of the upper cavity through the pipe. In blowing, the middle board is raised, by which means air rushes into the lower cavity, and in its descent forces air into the upper cavity, the valves preventing its return, and the weight on the upper board forces it out through the

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pipe in a continuous blast. Thus it will be seen, that the ascent of the middle board fills the lower cavity while the descent fills the upper cavity, and the weight of the top board drives the air out in a blast; thus the irregular puffing action of the single bellows is here confined to the lower board, which supplies air to the upper cavity. The blast, although continuous, is not, however, quite regular, for when the air is forced into the upper cavity, an excess of pressure is communicated to the air contained therein, but this is of no consequence in a smith's forge.

This construction will be understood by reference to the bellows in Halley's portable forge, Fig. 119, in which a a is a square frame of iron passing round the whole; b b, pillars supporting the platform or hearth Fis- HB.

for the forge fire; d, the bellows made fast by the middle flap to the frame a, and worked by the handle e, inserted in a socket at the top of the lever f; this lever and a corresponding arm on the opposite side, swinging upon pivots mounted on the sides of the frame a, and connected by a rod g, which passes across the machine under the bellows. By depressing the handle e, the levers / liit the rods and the bottom flap of the bellows, and on lowering the handle this flap falls by its own weight, thus producing the blast for working the forge. The flaps are covered with iron plates to increase the effect, and * arc nearly square to afford greater space. The collapsing of the upper flap forces the blast up the pipe h to the fire. To make this furnace portable, the parts arc taken asunder, and the bellows and frame arc placed on the hearth e, the pipe h and the legs b are packed on the top and sides of the bellows, and the whole is shut up in a box, formed by the hearth of the forge with its side plates; the cover is then turned down by its hingejoints upon the box, and secured by a hasp and padlock.

The smith's bellows is worked by means of a rocker, with a string or chain fastened to it. By drawing down the handle of the rocker the movable board rises. The smith's bellows is sometimes made circular, the boards being in a horizontal position, parallel to each other, as in Fig. 121, in which A is the blast-pipe, B the movable lower board, c the fixed board with the pipe inserted, D the upper moveable board loaded with a weight. Motion is given

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will be 113.19 inches, and the upper board would require a weight of 66.5 lbs. for a blast equivalent to a pressure of Jlb. on the square inch, or a velocity of 207 feet per second, a blast well adapted to a smith's forge. The force of the blast can be varied by altering the diameter of the pipe, for which a special contrivance is sometimes made. In portable forges, the boards are brought together by means of helical springs instead of weights.

In some of the native furnaces for smelting iron ore in Hindostan two bellows made of skin are used; a pipe projects from the bottom of each, and is

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of the furnace is an ingenious contrivance for preventing the twyere from rising when the bellows is draw n up. It consists of a bar, the bottom of which presses on the end of the twyere, while its tip hitehes into a loop of iron placed between two lateraal stnds or staples. The dotted line shows the form of the hearth, and the direction of the flue.

A very simple form of bellows, perhaps the simplest, is that used by the Chinese smiths. It consists of a square pipe of wood, Fig. 123, with a square board B exactly fitting it, which is moved to

Fty. 123.

and fro by means of a handle h. At the further end is the blast-pipe p, and in each side is a valve (shown by the dotted line) opening inwards.

A very ingenious and powerful blowing machine, founded on the principle of the Chinese bellows, was constructed some years ago by Mr. Vaughan, and is described in the Encyelopaedia Britannica. It consists of two square boxes placed side by side. A piston, r i', Fig. 124, filting each, is

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drawn backwards and forwards by means of the rod it, working horizontally on wheels w w, by means of the spear s, which communicates with the crank of a wheel at some distance off. The body of the piston is a cast-iron plate with a socket in the middle to receive the rod; the diameter of the piston is about i of an inch less than that of the box, and it is made tight by the following ingenious arrangement. Two pieces of wood, w, are cut diagonally to receive pieces of leather, / /, between them, and both the leather and the wood are firmly bolted to the plate of the piston i. The leathers extend about two inches beyond the wood, and their slight elasticity keeps them in contact with the metallic surface, so t hat when the piston is in motion the leather ou one side claps close to the surface, rendering it air-tight, while the leather on the other side is loose.

The projecting curved pipes, I i', communicate between the box where the piston works and the airchest c. When the piston moves from A to B, the valves 1, 3 open, whde 2, 4 remain shut. The air contained in the box is foreed through the valve C, into the chest c, and thence along the blast-pipe B P. In the return stroke, which is the whole length of the box, the valves 1,3 arc shut, while 2, 4 are open, and the air is forced through 5 and then along B p.

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Two of these machines work at the same time by two cranks, so that one is in full blast while the other is returning the stroke; hence there are 4 puffs produced by 2 double strokes, and these occurring alternately at almost equal intervals, a steady blast is produced. Mr. Vaughan recommends that four of these boxes be at work at once, so as to produce 8 puffs in one double stroke, which if divided by equal intervals, produce a sufficiently uniform blast for any purpose. The machine makes 70 strokes per minute; the nose-pipe, where the blast enters the furnace, is 2} inches in diameter, and discharges 1,200 cubic feet per minute.

A uniform blast is also produced by the arrangement shown in Fig. 126, in which two cylinders are

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connected with each other and with the discharge pipe, p is the working piston, which is worked by a rod connected by double chains with the arched head of a working beam moving round a gndgeon. By the descent of this piston, the air is compressed and forced through the valve v, while the loaded piston L is raised to its highest point. The piston p now ascends, and its cylinder is filled with air through the valve v', during whioh time the loaded piston gradually descends. The valve v is closed by the pressure and the air is forced out through the discharge pipe d. Before all the air in the cylinder L is discharged, it receives a fresh supply by the descent of r, and thus while the engine is in motion the blast is rendered continuous.

The trompe, or water-blowing engine, Fig. 127, is an ingenious and economical method of obtaining a blast. It is used in Savoy, Carniola, and in America. It is formed of two pipes or funnels, one of which is at b, set upright, and terminating above in a cistern of water <?, and bflow is a tub or drum e. The conical part p, just below the cistern, is called the etranguillon, and prevents the water discharged into the trompe from filling the pipe in falling, but divides it into many streamlets. Below this narrow part a number of holes q q are perforated obliquely, through which air is admitted and carried by the water in its descent. The air parts with the water by dashing upon a castiron slab d within the drum. At the bottom of the drum is Rn aperture / for the escape of the water,

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but to prevent the air from escaping with it, the water as it issues is received into a chest l m n o, divided into two parts by a vertical slide-plate between

m n. By raising or lowering this plate the water may be maintained at any required level within the drum, so as to give the inclnded air a greater or less pressure. The water finally drains off by the hole o. To the upper part of the drum is fitted the air pipe e f, divided at the point f into three tubes, the principal of which is for the cupellation furnace, and the other two at g for the smelting furnaces. Each of these tubes ends in a leather socket and an iron nose-pipe k adjusted in the twyere of the 11 furnace. A flood-gate fitted in

"| JL the upper cistern a regulates

the admission of water. The usual height of this apparatus is about 26 feet to the upper level of the water cistern. Its total length is 36£ feet, and its width 2 feet to give room for the drums.

One of the most powerful and perfect blowing machines in the kingdom is that at Woolwich dockyard, which is used for supplying air to forty forge fires, amongst which are several fires for forging

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