Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/701

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MANUFACTURE.] W O O L 661 rollers, which thus deliver four continuous slivers of top, and leave the noil to be otherwise lifted out of the teeth. The sliver as delivered from the combing machine is made up into a ball by a balling gill-box, behind the back rollers of which instead of a can there is a large bobbin for receiving the sliver, which is wound on it in a diagonal manner from the oscillating rotation given to the bobbin. Such balls of sliver then undergo the operation of drawing, the purpose of which is still further to equalize the strand of iibre, and to bring it into a sufficiently attenuated form for spinning. The principle of drawing or draughting consists in presenting the sliver to a pair of receiving rollers which pass it on to a pair of delivery rollers, which rotate proportionately faster than the receivers, and to that extent draw out and attenuate the .sliver. Supposing the wool to pass through six such drawing frames, six slivers may be fed into the first and drawn out to the dimensions of one ; the same may be repeated in the second, five slivers may be reduced to one in the third, four to one in the fourth and fifth frames ; and in the roving frame, in which a little twist is given to the sliver before it is wound on a bobbin, two slivers may be elongated into one. Thus we have any length of sliver drawn out 6x6x5x4x4x2 = 5760 times its original extension, and with increase of frames this extension multiplies enormously. Treating the slivers in nine drawing frames, we may have 8x6x 5x5x5x4x3x2x2 = 288,000 of extension. Short and medium staple wools are carded before being gilled and combed. The preliminary operations differ in no way from those employed for woollen yarns. After carding the wool is generally washed, previous to gilling in a back washer. The machine consists of two sud bowls or vats provided with immersers and squeezing rollers through which the cardings are passed ; then they are carried round two copper cylinders internally heated by steam, from which they are passed on and delivered by the fallers of a gilling apparatus. The bobbins of elongated and slightly twisted rovings are now ready for spinning on the throstle spinning-frame, on which it is simultaneously drawn out to its ultimate tenuity, twisted, and wound on a bobbin. The drawing out is done practically by the same device as the drafting of sliver in the drawing-frame. The bobbins of rove are placed on pegs on the frame slightly canted forward, so that the roving as drawn off comes away at right angles from the bobbin. The rovings pass first between a pair of rollers, and are carried on and supported by small carrier rollers till they reach a front pair of rollers, the upper of which is covered with leather and the lower grooved or furrowed. The space between the back and front pairs of rollers, termed the ratch, is that in which the final drawing is effected, and the amount of attenuation effected is dependent on the relatively faster rate at which the front rollers rotate as compared with the back pair. Immediately the slender cord has passed the front pair of rollers, twist is imparted to it by the spindle working either on the old flyer principle, on the cup principle, or with the more recent ring and traveller. See also YARN. The doubling and subsequent treatment of worsted singles are the same as in the case of woollen yarn singles from, the mule frame. The term shoddy was formerly one of some opprobrium in con nexion with woollen manufactures, but the substance is now frankly recognized as a material of great utility for many purposes when body and warmth are more essential than toughness or elasticity. Shoddy consists of rags and shreds of stockings, flannels, and other softworsted fabrics torn and reduced to such fragments of the original fibre as can be made by the operation. Mungo is a similar pre paration made from rags, and from shreds and clippings of milled woollen cloths, being divided into new mungo made from tailor s waste, and old mungo from rags of all degrees of degradation. Extract wool is that which is recovered from rags of various cloths in which cotton and wool are variously woven together. The wool is freed from the cotton by the same chemical or carboning process which is employed in freeing dirty wool from burrs, viz. , by treating the union fabric with a solution of sulphuric acid and heating it in n stove, when the acid energetically attacks and chars the vegetable fibre, leaving the wool unharmed. Shoddy and mungo arc prepared by dusting the rags and fragments, classifying them according to colour ami quality, picking out seams, oiling the material, and then passing it into a machine significantly called the "devil," which literally rends the rags, &c. , to fragments, which look more like dust than fibres, by the exceedingly rapid rotation of a swift or large cylinder armed with powerful iron spikes, with equally strong toothed rollers revolving in an opposite direction. Into the same category with these come the flocks formed in the various pro cesses of finishing cloth, which are, of course, even shorter than the others. Indeed the shoddy manufacturers hold that "anything long enough to have two ends " is sufficient for manufacturing purposes. The shoddy trade was begun in Batley, Yorkshire, by Mr Benjamin Law in 1813, and, notwithstanding the disfavour with which it was long viewed, it prospered and developed till the shoddy district of Batley, Dewsbury, and their surroundings became the centre of a great and prosperous branch of the woollen trade entirely dependent on these disintegrated materials. It is said that as much as 125,000,000 K> of shoddy material is now yearly worked up into cloth in England alone. Shoddy, &c. , cannot bo used without a due proportion of natural-length wool, visually one-third of pure wool being employed in spinning shoddy yarn ; but sometimes as much as 80 per cent, of the finished cloth consists of shoddy. It finds its way into a very large proportion of woollen goods, but its use is detrimental where tenacity and wear are required. For linings, rugs, wraps, and heavy friezes, pilots, druggets, blankets, &c., in which bulk and warmth more than wear-resisting qualities are required, it is suitable, and it also makes into good light milled cloth for ladies jackets. Shoddy is practically a new source of textile material ; its employment is a utilization of waste, and fur nishes cheap serviceable textures. For the dyeing and weaving of woollen and worsted fabrics the Cloth reader is referred to the separate articles relating to these processes, finishing:. But a piece of cloth woollen cloth especially as it comes from the loom is very far from being a finished product. Indeed the most characteristic operations in woollen-cloth manufacture are subsequent to the weaving stage. Woollen cloth from the loom, called "roughers," has an irregular, slack aspect, very different from the same web when it comes to be sold as, say, broad-cloth. The web as it leaves the loom is still saturated with the oil with which it was sprinkled before spinning, and impregnated with the size applied to the yarn to give it tenacity and consistency in weav ing. To remove these it is scoured with hot soap-sud in a trough having a convex bottom, and fitted with wooden mallets which are made to fall obliquely against the cloth. After being scoured in this way, it is stretched in a frame for burling or perching, an operation which consists in going carefully over the whole web, picking out all burrs and knots in the texture, and darning up holes and open spots which it may show. Fulling is the one process which is specially distinctive of woollen Fulling, textures, its results being shown in the highest degree in broad cloths, doeskins, and other like goods. Every one knows how flannels, blankets, and hosiery tend to contract with frequent washing, gaining in thickness and solidity what they lose in exten sion and elasticity ; such shrinking is greatly accelerated when woollen articles are much rubbed in very hot water. This shrink ing or fulling is, as already explained, the result of the serrated wavy structure of wool. The operation of fulling or milling is performed in the fulling stocks, or in the more modern milling- machine ; but, by whatever agency carried out, the effect is always the same. The old method of fulling by the stocks is wasteful of power, and the blows the stocks give tend sometimes _to tear the cloth, drawbacks from which the milling-machine is comparatively free. The cloth to be fulled is well saturated with hot soap and water, and either worked under the falling weight of the stocks or pressed and rubbed between rollers in the milling-machine while so heated and soaped. The more prolonged the operation the more does the material shrink up and thicken, and a piece of cloth may even be milled till it is reduced to half its original length and breadth. The degree of fulling is a distinctive feature of many different varieties of cloth. In the treatment of broad-cloth, doe skins, meltons, and all nap-finished cloth, the milling is carried so far that the fibres become densely matted, obliterating the appear ance of weave, and giving the piece more the aspect of felt than of cloth. Fabrics such as Venetian cloths, and diagonals, &c., to which no pile-finish is given, are milled only to the extent of solidifying and increasing the substance and strength of the texture, and tweeds are only very slightly felted to give them a dressed surface. On the conclusion of the fulling operation the goods are scoured to free them from soap, which is very simply done by gradually supplanting the soap-sud with pure water, which is tepid at first but is gradually cooled by additions till in the end the cloth is being worked in pure cold water. The cloth that is taken from the falling-machine must immedi- Teasling. ately be stretched uniformly in all directions by hooks on a frame, so that it may dry evenly without wrinkle or curl. The frame may be placed in a hot-air chamber to hasten the drying, or the cloth may be allowed to dry under ordinary atmospheric conditions. In this operation a pile or nap is raised on the surface of milled cloth. The raising of the pile is effected by the agency of the flower-head of the teasle (Dipsacusfullonum), which forms a cone- like spike covered with imbricated scales. These scales end in sharp, recurved hooks, possessed of high elasticity, combined with just sufficient stiffness for the work they have to do. The use of these hooked teasles is to scratch the surface of the milled cloths, and getting entangled with minute surface fibres break these or pull out their ends, and so raise over the whole surface a fine but un equal nap. Formerly the teasles were set together in a flat frame, and by hand the workmen brushed them in a uniform manner over the whole surface of the tightly stretched cloth. But this labori ous handicraft has long been superseded by the use of the gig-mill or dressing-machine. This apparatus consists of a cylinder made to rotate at a high rate of speed. The surface of the cloth to be

raised is, in a state of uniform tension, brought in contact with the