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Worsted

finish, wool, nap, cloth, machine, rollers, woolen, thread, weaving and fulling

WORSTED tlANIFACTtRE. In making a worsted thread, if a comparatively short or medium staple fibre is used, the wool is first carded as in woolen manufacture. But if a very long staple wool is used. having a fibre five inches or more long, the wool is not carded at all, because the fibre would be broken by the cylinder engaging it before it was released from the preceding cylinder. There is still a third class of worsted yarns, such as are required for carpet-weaving, where a soft open thread is desired, which are not combed at all, but are carded, drawn, and spun. With the exception of this third class of worsted ':urns, the first distinctive operation, af ter the wool has received the preliminary treat ment already described, is gilling. The object of gilling is to level the fibres and make them parallel. The machine by which this is aeeom 'dished consists of a pair of rollers which catch the wool, and of a second pair of rollers, which draw it forward over heavy steel bars, called (oilers, covered with projecting steel pins. The machines are generally used in sets, each succes sive machine having the pins on the rollers finer and more closely set than the preceding. The wool is fed to the rollers; it is caught by the rows of steel pins which rise in close and con stant succession and penetrate the wool pre sented to them, traveling forward with it to the second pair of rollers, which in their turn catch the fibre and draw it away. The Milers are so called because when they accomplish their jour ney, they, by the aid of the agency of an endless screw mechanism, fall down, and by the action of other endless screws are returned to their original position. There is thus a continuous lice of falters traveling between the feed-rollers and the back-rollers. and there is a steady and constant drawing of wool away from the front rollers and through the teeth of the falters. Five or six of these machines usually constitute a set. They are all constructed on the same principle, but with the pins finer and more closely studded as the fibre travels onward. In the first three machines it is usual to have the wool delivered in the form of a broad lap, but in the later ma chines, or gill-ba.res, as they are called, the prod uct is condensed into a slicer and is received in large cylindrical cans. Six of these cans are brought to the front of the next gilling machine, and the six slivers are fed in, and passing through are drawn into and delivered as one. The operation is repeated three or four times, and the fibres are brought even with each other and a very level and uniform thread produced.

After the worsted has been gilled and combed it is put through drawing machines, much like those used in cotton-spinning. It is then spun, the worsted thread being twisted much harder in spinning than woolen thread. The spun yarn is now reeled, warped, beamed, sized, and other wise prepared for weaving.

For the process of weaving, the articles on WEAVING and Looms should be consulted. The woven fabric requires several supplementary operations. The character and appearance of woolen fabrics is more altered by these finishing operations than any other material. Indeed, dif ferent fabrics may owe their distinctive pe euliarities wholly to their finish, the process of manipulation up to this point being exactly iden tical. In woolen goods, owing to the nap and its felting power, patterning is much less effective than in the weaving of worsted, hut a greater variety of effects due to the character of the finish is possible. Among the principal varieties of finish of woolen goods are the dress-faced or doeskin finish, the velvet or erect pile finish. the

Scotch or AleIton finish, and the bare-faced finish. In the dress-fare finish the nap is raised and spread in one direction over the face of the cloth so as to hide completely the warp and weft threads. To this class belong broadcloths, bea vers, and the other woolen fabrics having a nap. The velvet finish is another form of finish with a heavy nap. In overcoatings and similar ma terials the nap is formed in little curls on the outer surface of the goods. In other goods it is left standing out like velvet. In the bare face finish the nap is sheared off completely. While the process of finishing the woven fabric differs according to the character of the desired finish, the general method is the same. The first step is known as fulling or milling. The opera tion of fulling, or milling, is to saturate the cloth with hot soap and water, when it is worked either by the fulling stocks or the fulling ma chine, or pressed and rubbed between rollers in the more modern milling machine. The more the cloth is soaked and beaten, the more it will shrink. and the operation can be carried on till the cloth is reduced to half its original length and breadth. The degree of fulling is a distinc tive feature of many varieties of goods. In broadcloths, and all kinds of nap-finished goods, the milling is carried on until the fibres become densely matted, and the appearance of weaving is entirely obliterated. Venetian cloths and di agonals, to which no pile-finish is given, are fulled or milled only enough to give them solidity and strength. Tweeds have still less. The proper stage of beating o• rolling having been reached, the soapsuds is gradually supplanted with pure water, tepid at first, but each new supply being cooler, until the fabric is finally worked in thor oughly pure and cold water.

On being taken from the machine the cloth Is stretched uniformly in all directions by hooks on a frame, that it may dry without wrinkle o• curl. At this stage the operation of teasling is entered upon. This is the raising of the pile or nap by the agency of the cone-like spike-head of the teasel, a plant of the genus Dipsacus. The head is covered with imbricated scales w•hieh end in sharp reeurved hooks of great elasticity, hut stiff enough to do the work required. The work was formerly done by hand manipulation, bit is now accomplished by the gigging machine, or gig mill, where the teasels are arranged on the face of revolving cylinders before which the fabric is made to pass. By this operation the loose ends of the wool are drawn to the surface, thereby forming the nap. Wire teasels are sometimes used, but nature's creation of the vegetable teasel is regarded as having never been improved upon.

The pile is now trimmed to produee uniform surface. Formerly the work was done by humid with huge shears, but now a machine containing a cylinder armed with a series of helical knives, and made to revolve with great rapidity, is em ployed. The machine was invented by Leonardo da Vinci, lint not brought into practical use until 400 years later.

The final process is the brushing of the cloth, winding it tightly around a huge drum, and hn thersing it in hot water. It remains in that condition for three o• form• hours, whirr it is un wound, the ends reversed and rewound, and again the cloth is subjected to the hot-water process. The closing act in its manufacture is the pressing in a hydraulic press, during which time steam is forced through it, this last proceeding adding to the solidity and smoothness of the cloth, and developing the lustre characteristic of a well finiihed fabric.