Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/698

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658 WOOL [MANUFACTURE. by the more absorbent vegetable matter, and the high heat causes it to combine so energetically with the water left in the burrs that the vegetable matter becomes com pletely carbonized. The wool is thereupon washed in water rendered sufficiently alkaline to neutralize any free acid which may remain, and dried. The same burr- removing effect is obtained by the use of a solution of chloride of aluminium, a method said to be safer for the wool and less hurtful to the attendant workmen than is the sulphuric acid process. For mechanical removing of burrs, a machine something like the Willey in appearance is employed. The main feature of this apparatus is a large drum or swift armed with fine short spikes curved slightly in the direction in which it rotates. By a series of beaters and circular brushes the wool is carried to and fed on these short spikes, and in its rotation the burrs, owing to their weight, hang out from the swift. The swift as it travels round is met by a series of three burring rollers rotating in an opposite direction, the projecting rails of which knock the burrs off the wool. The burrs fall on a grating and are ejected, with, of course, a good deal of wool adhering to them, by another rotating cylinder. Oiling. There remains yet another preliminary operation through which wool generally has to pass previous to the spinning processes. As delivered from the drying apparatus the wool is bright and clean, but somewhat harsh and wiry to the touch owing to the removal of the yolk which is its natural lubricant. To render it properly soft and elastic, and to improve its spinning qualities, the fibre is sprinkled with a percentage of oil, comparatively small quantities by some spinners none being used for worsted wools, but a larger amount being applied in the oiling of wool for woollen manufactures. The oil further has the advantage of producing a certain adhesiveness of the fibre in the spinning process, and thus it enables the spinner to get a more level and finer yarn, and it prevents loss from the flying off of separate fibres. As the oil is a costly item, it is of consequence that it should be equally distributed and used in a thrifty manner, for which end various forms of oiling apparatus have been devised, which sprinkle the oil in a very fine spray over thinly distributed wool carried by an endless cloth under the sprinkler. Gallipoli olive oil is the best medium for oiling combing wool ; and for carding wool the liquid olein expressed from tallow and lard in the preparation of stearin is employed with advantage. Blending. The raw material is now ready for the various spinning and other processes by which it is worked into useful forms ; but pure wool of one quality alone is not gene rally used in the production of woven fabrics. For many reasons among which cheapness figures prominently wools are blended, and to no inconsiderable extent the added material consists of shoddy, mungo, or extract wools (see below). Blending with cotton is also practised, and for some purposes silk and wool are mixed. The question of colour as well as quality also determines blending opera tions, natural coloured wools being frequently intermixed to obtain particular shades for tweeds, knitting yarns, &c. The various materials to be intermixed are bedded in due proportion in separate layers over each other, and passed through a teazer, from which they issue so intimately intermixed that they present a uniform appearance. Woollen The processes hitherto described although woollen manufacture has been specially kept in "View are more or less essential to wool for all purposes to which it is applied. But from this point the manufacturing opera tions diverge into three main channels, which may be regarded as almost distinct textile industries. First and simplest we have the felt manufacture, in which cloth is made without either spinning or weaving ; second is the factures. woollen yarn and cloth manufacture, embracing the pre paration of carded yarns and of cloth which is so milled or felted as to have the appearance of felt; and, thirdly, in the worsted yarn and cloth industry combed yarn is prepared and cloth showing the yarn and pattern is woven. These definitions must be taken to be accurate only in the broad general acceptation. Felt is a kind of cloth made without spinning or weaving, but Felt, simply by the mutual adhesion of the imbricated fibres. The peculiar property is most distinctly developed in the short or carding wools, but all wool, in common with mohair, alpaca, vicugna, and camel s hair, possesses it. Felting properties are also found in the hair of other animals; the rabbit, especially, supplies the finer felts used for hat-making, while the beaver hat, which is the ancestor of the modern dress hat, was a felt of beaver hair. Felted cloth is made by the combined influence of heat, moisture, and pressure or rubbing on a uniformly spread-out mass of woollen fibres. The wool is scribbled or carded out into a uniform lap of extreme thinness, but of a length and breadth sufficient for the size of the cloth to be made. A series of these carded laps are superimposed on each other till the requisite thickness of material is attained, and gene rally the two external laps are made of material superior to the body. The lap so prepared is passed on between a series of pairs of rollers, which press against each other partly immersed in a trough of water, the upper rollers being solid and heavy while those under are hollow and heated by steam. To the upper rollers a gentle reciprocating motion is communicated, so that the material is felted as it passes on. When duly condensed, the cloth, of leathery consistence, is dyed, printed, dressed, and finished, when required, like ordinary woollen cloths. Felt has extensive appli cations, there being made from it druggets, carpets, table-covers, horse-cloths, &c. ; the coarser varieties are used for boiler-covering and other mechanical purposes. It becomes necessary here to indicate the specific distinction of Woollen woollen and worsted yarns and cloth. In a general way it may be and said that woollen yarns are those made from short wools possessed worsteds of high felting qualities, which are prepared by a process of carding, whereby the fibres are as far as possible crossed and interlocked with each other, and that these cardings, though hard spun on the mule frame, form a light fluffy yarn, which suits the material when woven into cloth for being brought into the semi-felted condition by milling which is the distinguishing characteristic of woollen cloth. On the other hand, worsted yarns are generally made from the long lustrous varieties of wool ; the fibres are so combed as to bring them as far as possible to lie parallel to each other ; the spinning is done on the throstle frame, and the yarn is spun into a compact, smooth, and level thread, which, when woven into cloth, is not milled or felted. At all points, however, woollen and worsted yarns as thus defined overlap each other, some woollens being made from longer wool than certain worsteds, and worsteds being, when made from short staple wool, also carded as well as combed ; and occasionally worsted yarn is spun on the mule frame, while nulling or felting is a process done in all degrees, woollen being sometimes not at all milled, while to some worsteds a certain nulling finish is given. The fundamental distinction between the classes rests in the crossing and interlacing of the fibres in preparing woollen yarn, an operation confined to this alone among all tex tiles, while for worsted yarn the fibres are treated, as in the case of all other textile materials, by processes designed to bring them into a smooth parallel relationship to each other. Woollen yarns, as above explained, are exclusively made by the Carding, process of carding. The simple apparatus the hand-cards with which carding was done before the introduction of machinery and factory-work consisted of square or oblong pieces of board with handles, one face of the board being covered with card leather, which was closely studded with fine elastic steel teeth, pointed in one direction and bent as in fig. 3. These teeth were strong or fine according to the nature, length, and strength of the fibre to be carded, but the finer the teeth the more closely were they studded together. A quantity of teased and oiled wool was placed on the surface of one card, which, taken in the left hand, was held teeth FIG. 3. Card Teeth, upward on the lap of the operator, while the other card, held in the right hand teeth downward, and consequently pointed in an opposite direction, was drawn from end to end over it, each card thus taking up a share of the wool which became entangled in its teeth. In this way, by drawing the one card over the other repeatedly, the whole of the wool was ultimately separated and equally distributed over the pair of cards. The wool was then stripped out of the cards by drawing the teeth of one through those of the other in the direction of their inclination. The carded wool thus lifted out was condensed into a loose but uniform round pipe or "carding" by rolling on the back of the card, and these

cardings were then ready for spinning on the wheel.