the other end comes round nearly to the same point, and is fastened to a long lever, i, called the brake lever. When this lever is lifted up, the brake is lifted off from the wheel, and does not touch it on any part, and the wheel and sails can turn; but when the lever is suffered to fall down, the brake closes round the wheel, and prevents the wheel and sails from turning. The brake lever is lifted up by a rope, k, which hangs down in reach of the miller when standing on the stage, II, built round the mill for the purpose, as also for clothing or unclothing the sails. When the brake is to be held up for any length of time, while the mill is at work, the brake rope is hooked on a hook driven into one of the uprights, BB. The head of the mill can be turned round upon the thirty-six rollers, to set the sail round in the proper direction to meet the wind. The fixed kirb, D D, has a ring of cogs all round its outside, which work with a pinion on a spindle, , turning in a socket fixed by iron braces. To the moveable head of the mill, on the upper end of the spindle, 7, a crown wheel is fixed, which is turned by a small pinion on the same spindle, with a wheel, m, round which an endless rope runs, and which hangs down in reach of the miller when on the stage, I. By pulling down one side of the endless rope he turns the wheel, m, and by the pinion the crown wheel, and its pinion, which acting against the teeth in the kirb, D, turns the head round upon the thirty-six rollers, and puts the sails in any position according to the wind is a roller turned upon an iron pin fastened to the under side of the beam, b, and acting against the inside of the kirb; another similar roller is fixed to the other beam, which is parallel to b; their use is to keep the head steady upon the rollers, otherwise the head might be thrown backwards by the action of the wind upon the sails. The upper part of the head is light framing and thin boards, covered with copper just to exclude the rain. The main cog-wheel, ǹ, turns a trundle, K, on the upper end of a long vertical shaft, L L, which comes down to the ground, and turns in a socket supported on Masonry at M: p is a crown wheel of fifty-six teeth turning another wheel of seventeen teeth on horizontal, which has riggers, g, on it to turn bolting mills and dressing machines in the upper room. In the lower room a large spur-wheel, t, of seventy-two teeth, is fixed, and turns a nut on each side of it, one of twenty-eight,

the other of twenty-six teeth, on the spindles of their respective mill-stones, r and s.

The construction of the mill for grind. ing flour is well explained in the article MILL, to which we refer our readers.

WIND sails, in a ship, are made of the common sail cloth, and are usually between twenty-five and thirty feet long, according to the size of the ship, and are of the form of a cone ending obtusely: when they are made use of, they are hoisted by ropes to about two-thirds or more of their height, with their bases distended circularly hoops, and their apex hanging downwards in the hatchways of the ship; above each of these one of the common sails is so disposed, that the greatest part of the air rushing against it, is directed into the wind-sail, and conveyed as through a funnel, into the upper parts of the body of the ship.

WINDAGE of a gun, the difference between the diameter of the bore, and the diameter of the ball.

WINE. See FERMENTATION, &c. All wines contain an acid, alcohol, tartar, extract, aroma, and a colouring matter. The presence and nature of each of these principles may be ascertained in the following way. 1. Acid. All wines, even the softest and mildest, redden litmus, and therefore contain an acid. This abounds, however, chiefly in the thin wines of wet and cold climates, where the grape juice or must contains but a small portion of sugar. When wine has been boiled to extract the brandy, the liquor that remains in the still, and is thrown away as useless, is a sour nauseous fluid, with an acrid and burnt flavour. When filtered and allowed to remain at rest for a time, it deposits a good deal of extractive matter, becomes covered with mould, and then contains a notable quantity of acetous acid, which may be separated by distillation. The acid is, however, not entirely acetous, at least not till after standing a considerable time, for it precipitates and forms an insoluble salt with lime water, and with the soluble salts of silver, lead, and mercury, and appears to be the malic acid mixed with a little citric, both of which are converted into vinegar by spontaneous decomposition. The wines that contain the greatest quantity of these acids yield the worst brandy, nor is there any method yet known of se parating or neutralizing the acid without materially injuring the quality, or lessening the quantity of the ardent spirit. 2.

Alcohol. The existence of this principle and mode of extraction by distillation has been fully described under the article brandy. The quantity of alcohol varies prodigiously. The strong, rich, full-bodied wines of the warmer vine countries will yield as much as a third of ardent spirit; whilst the thin light wines will often give no more than about one-sixteenth of the same strength. 3. Tartar. This substance has also been fully described in its proper place. Tartar is not altogether a product of the fermentation of wine, since it is contained in must, though in small quantity. 4. Extract. Must contains an abundance of extractive matter, which materially assists the fermentation, and is afterwards found, in part at least, in the lees, but another portion may be obtained from the wine by evaporation. It is also extract that mixes with and colours the tartar. By age the quantity of extractive matter diminishes. 5. Aroma. All wines possess a peculiar and grateful smell, which would indicate a distinct aromatic principle, but it has never been exhibited in the form of essential oil, or condensed in any smaller quantity by distillation or any other mode. To give wine all its aroma it should be fermented very slowly. 6. Colouring matter. The husk of the red grape contains a good deal of colour, which is extracted when the entire fruit is pressed, and becomes dissolved in the wine when the fermentation is complete. Many substances will separate the colour. If lime-water is added to high-coloured wine, a precipitate is formed of malat of lime that carries down with it all the colouring matter, which cannot again be separated either by water or alcohol. But if wine alone is evaporated gently to dryness, and the residue treated with alcohol, the colouring matter dissolves therein. We may add too, that the natural colour of wine is entirely and speed ily destroyed by the addition of hot well-burnt charcoal in pretty fine pow der. The colour of red wine in the state in which we receive it is not entirely that of the grape, but is given by other colouring substances, which, however, are quite innoxious.

WINGED, in botany, a term applied to such stems of plants as are furnished all their length with a sort of membranaceous leaves, as the thistle, &c. Winged leaves, are such as consist of divers little leaves, ranged in the same direction, so as to appear only as the same leaf. Such

are the leaves of agrimony, acacia, ash, &c. Winged seeds, are such as have down or hairs on them, which, by the help of the wind, are carried to a dis

tance.

WINGS, in heraldry, are borne sometimes single, sometimes in pairs; in which case they are called conjoined. When the points are downward, they are said to be inverted; when up, elevated.

WINGS, in military affairs, are the two flanks or extremes of an army, ranged in form of a battle; being the right and left sides thereof.

WINGS, in fortification, denote the longer sides of horn-works, crown-works, tenailles, and the like out-works; includ ing the ramparts and parapets, with which they are bounded on the right and left from their gorge to their front.

WINTERA, in botany, so named from Captain William Winter, who brought the bark of this tree from the Straits of Magellan, a genus of the Polyandria Tetragynia class and order. Natural order of Magnolia, Jussieu. Essential character: calyx three-lobed; 'petals six or twelve; germs club-shaped; styles none; berries four or eight, obovate. There are three species.

WIRE drawing, the art of drawing out long bars of metal, by pulling it through holes in a plate of steel, or other fit metallic compound. In order that a wire may be drawn, it is requisite that the metal should have considerable tenacity. Gold, silver, iron, steel, copper, and their compounds, are most commonly used in the arts. The process is of considerable simplicity. A number of holes, progressively smaller and smaller, are made in a plate of steel, and the pointed end of a bar of metal being passed through, one of them is forcibly drawn by strong pinchers, so as to elongate it by the pressure arising from the re-action of the greased hole: this is the wire; and it is again passed in like manner through another hole a little smaller; and, by continuing the process, the wire has its length increased, and its diameter diminished, to a very great degree. The largest wire may be nearly an inch in diameter, and the smallest we have seen was about onethousandth part of an inch; but we are assured that silver wire has been made one-fifteen-hundredth of an inch in diameter. The size of these small wires may be ascertained from the weight of a known measure of length, and the specific gravity of the metal. Or, less correct

ly, the wire may be wound round a pin, and the number of turns counted which make a given length.

Wires are drawn square, and of other figures in their sector. In particular they are drawn grooved, so that any small part will form the pinion of a clock or watch work.

As the violent action of the drawing plate renders the wires hard and brittle, it is necessary to anneal it several times during the course of drawing. Very small holes are made by hammering up the larger, and the point, in very thin wire, is made by rolling or crushing the end by a smooth burnishing tool upon a polished plate.

It is said that soft steel is as good for the wire drawer's plate as that which is hard, or as the compound material which comes from France in wire plates, and is highly esteemed. This has not been yet chemically examined.

WIRE of Lapland. The inhabitants of Lapland have a sort of shining slender substance in use among them on several occasions, which is much of the thickness and appearance of our silver wire, and is therefore called, by those who do not examine its structure or substance, Lapland wire. It is made of the sinews of the rein-deer, which being carefully separated in the eating, are by the women, after soaking in water, and beating, spun into a sort of thread, of admirable fineness, and strength, when wrought to the smallest filaments; but when larger, is very strong, and fit for the purposes of strength and force. Their wire, as it is called, is made of the finest of these threads, covered with tin. The women do this business, and the way they take is to melt a piece of tin, and placing at the edge of it a horn with a hole through it, they draw these sinewey threads, covered with the tin, through the hole, which prevents their coming out too thick covered. This drawing is performed with their teeth and there is a small piece of bone placed at the top of the hole, where the wire is made flat, so that we always find it rounded on all sides but one, where it is flat. This wire they use in embroidering their clothes as we do gold and silver; they often sell it to strangers, under the notion of its having certain magi. cal virtues.

WIT, a faculty of the mind, consisting, according to Mr. Locke, in the assembling and putting together of those ideas, with quickness and variety, in which any re

semblance or congruity can be found, in order to form pleasant pictures and agreeable visions to the fancy. This faculty, the same author observes, is just the contrary of judgment, which consists in the separating carefully from one another, such ideas wherein can be found the least difference, thereby to avoid being misled by similitude and affinity, to take one thing for another. It is the metaphor and allusion, wherein, for the most part, lies the entertainment and pleasantry of wit, which strikes so lively on the fancy, and is therefore so acceptable to all people, because its beauty appears at first sight, and there is required no labour of thought to examine what truth or reason there is in it. The mind without looking any further, rests satisfied with the agreeableness of the picture, and the gaiety of the imagination; and it is a kind of affront to go about to examine it by the severe rules of truth or reason. Wit is also an appellation given to the person possessed of this faculty; and here the true wit must have a quick succession of pertinent ideas, and the ability of arranging and expressing them in a lively and entertaining manner; he must at the same time have a great deal of energy and delicacy in his sentiments; his imagination must be sprightly and agreeable, without any thing of parade or vanity in his discourse but it is not, however, essential to the character of a wit, to be ever hunting after the brilliant, studying sprightly turns, and affecting to say nothing but what may strike and surprise.

WITENA-mot, or WITENA gemot, among our Saxon ancestors, was a term which literally signified the assembly of the wise men, and was applied to the great council of the nation, of latter days called the parliament.

WITHERINGIA, in botany, so named in honour of William Withering, M. D. F. R. S. a genus of the Tetrandria Monogynia class and order. Natural order of Luridæ. Solaneæ, Jussieu. Essential character: corolla subcampanulate, with four bumps in the tube; calyx very small, indistinctly four-toothed; pericarpium two-celled. There is only one species; viz. W. solanacea, a native of South America.

WITHERITE, in mineralogy, a species of the genus Barytes: it is commonly of a light yellowish grey colour, usually massive, but sometimes crystallized: specific gravity about 4.3. It melts without addition before the blow-pipe into a white

It occurs in veins, heavy spar, lead glance, blende, and calamine, and is found in Lancashire. It is a very active poison, but com. bined with muriatic acid, it may be used with great caution in cases of scrophula.

WITNESS, in law, one who is sworn to give evidence in a cause. If a man be sub. pænæd as a witness upon a trial, he must appear in court on pain of 1007. to be forfeited to the king, and 107. together with damages equivalent to the loss sustained by the want of his evidence to the party aggrieved. But witnesses ought to have a reasonable time, that their attend ance upon the court may be of as little prejudice to themselves as possible; and the Court of King's Bench held, that notice at two in the afternoon to attend the sitting that evening at Westminster, was too short a time.

Where a witness cannot be present at a trial, he may, by consent of the plaintiff and defendant, or by rule of court be examined upon interrogatories at the judge's chambers. No witness is bound to ap pear to give evidence in a cause, unless his reasonable expense be tendered him; and if he appear, till such charge is actually paid him, except he both resides and is summoned to give evidence within the bills of mortality. See ARREST, EVIDENCE, PRIVILEGE.

WITSENIA, in botany, a genus of the Triandria Monogynia class and order. Na tural order of Ensatæ. Irides, Jussieu. Essential character: corolla one-petalled, cylindrical, six-parted; stigma emargi nate: capsule superior. There is only one species; viz. W. maura, a native of the Cape of Good Hope, WOAD. See ISATIS. VOL. VI.

It occurs in primitive mountains, and in the oldest formations. It is usually accompanied with tin, and distinguished from tin-stone by its streak, which is reddish brown, whereas that of tin-stone is grey. See TIN.

WOOD. See TIMBER. The wood of vegetables consists of fibres, impregnated with a variety of the natural juices of the plant, as mucilage, resin, colouring matter, extract, essential oil, sugar, &c. All of these may be obtained from one or other kind of wood, by applying those menstrua which dissolve these substances in their natural state. If a piece of wood be boiled in a great quantity of water, till it no longer gives out taste or smell, and if it be afterwards digested in alcohol, the substance which remains is the woody fibre. It is either in a fibrous, lamellated, or pulverulent form. This substance, which is more or less coloured, has neither taste nor smell; is not altered by exposure to the air; and is insoluble in water and alcohol. When it is heated in contact with air, it blackens, exhales dense, acrid pungent fumes, and leaves behind a coaly matter, which does not change its form. By reduc ing it to ashes, it is found to contain a little potash, sulphate of potash and lime, and 4 E

phosphate of lime. When it is distilled in a retort it yields water, acetic acid contaminated with oil, a thick oily matter, carbonated hydrogen, and carbonic acid gases, and a portion of ammonia, combined with acetic acid. The pure ligneous fibre is decomposed by being heated with strong nitric acid, and yields a very considerable quantity of oxalic and malic acid. The surface of wood is readily stained by a variety of substances; and if these are allowed to remain in contact with it, they sink into the substance of the wood, which often produces a very agree able effect in cabinet work.

WOOD, cutting in, is used for various purposes; as for initial and figured letters, head and tail pieces of books; and even for schemes, mathematical and other figures, to save the expense of engraving on copper and for prints and stamps for papers, calicoes, linens, &c. The invention of cutting in wood, as well as that in copper, is ascribed to a goldsmith of Florence but Albert Durer and Lucas brought both these arts to perfection. About two hundred years ago, the art of cutting in wood was carried to a very great pitch, and might even vie, for beauty and justness, with that of engraving on copper: at present it is much neglected, the application of artists being wholly employed on copper, as the more easy and promising province: not but that wooden cuts have the advantage of those in cop. per in many respects; chiefly for figures and devices in books; as being printed at the same time, and in the same press with the letters: whereas, for the other, there is required a particular and separate impression. The cutters in wood begin with preparing a plank or block of the size and thickness required, and very even and smooth on the side to be cut: for this they usually take pear tree, or box; but the latter is best, as being closest, and least liable to be worm eaten. On this block they draw their design with a pen or pencil, exactly as they would have it printed; or they fasten the design drawn on paper upon the block with paste and a little vinegar, the strokes or lines turned towards the wood. When the paper is dry, they wash it gently with a sponge dipped in water, and then take it off by little and little, rubbing it first with the tip of the finger, till nothing is left on the black but the strokes of ink that form the design, which mark out what part of the block is to be spared or left standing. The rest they cut off very carefully with the points of very sharp knives, chissels,

WOOF, among manufacturers, the threads which the weavers shoot_across with an instrument called the shuttle.

WOOL, the covering of sheep. Each fleece consists of wool of several quali ties and degrees of fineness, which the dealers therein take care to separate.

The fineness and plenty of our wool is owing, in a great measure, to the short sweet grass in many of our pastures and downs; though the advantage of our sheep feeding on this grass all the year, without being obliged to be shut up under cover during the winter, or to secure them from wolves at other times, contributes not a little to it.

This substance, the material of such important manufactures, possesses some curious chemical properties, none of which however are much illustrated by the various operations performed on it in manufacture, almost all (that of dyeing excepted) being purely mechanical processes. Some of the simple chemical properties of wool have been examined by M Achard, and compared with the corresponding properties of the hair of different animals, The copious generation of oxalic acid by treatment of wool with nitric acid, has been particularly described and explained by M. Bertholet in his beautiful researches on animal matter; and the great solvent power of the caustic fixed alkalies, has been happily applied to some use by M. Chaptal, as a saponaceous compound.

Wool, in the state in which it is taken from the sheep, is always mixed with a great deal of dirt and foulness of different kinds, and in particular is strongly imbued with a natural strong smelling grease. These impurities are got rid of by washing, fulling, and combing, by which the wool is rendered remarkably white, soft, clean, light, and springy under the hand. When boiled in water for several hours in a common vessel, wool is not in any way altered in weight or texture, nor does the water acquire any sensible im pregnation.

The action of the nitric acid on wool is very curious. When cold, this acid only disengages a large quantity of azotic gas; but when warmed, much nitrous gas is given out, and at least two new acids are formed, viz. the malic and the oxalic, the