| 1814 1824 1834 1840 1850 | . . . | Bales. 165 1,620 16,926 44,502 158,558 | 1870 1890 1901 1903 | | Bales. 673,314 1,509,666 1,602,726 1,319,365 The following statistics give an idea of the development of the colonial and foreign wool trade as gauged by the London wool sales It must not be forgotten, however, that a large quantity of S. American, W. Indian, Russian, &c., wools, along with mohair and alpaca, come through Liverpool, and consequently are not taken into account here. With reference to wools grown in the United Kingdom the truth seems to be that a fine short wool has never been produced. English wool is known the world over as being of a long and lustrous type, which was doubtless that so much in wools. YP demand in the middle ages. That it was as long and lustrous as the typical Leicester or Lincoln of to-day is doubtful, as the new Leicester breed of sheep was only fully developed by Mr Bakewell after the year 1747, and the latter day Lincoln was even a later development of a similar character. What the exact type of English wool or wools was prior to the 18th century will probably never be decided, but from the closing years of that century there is no difficulty in being fairly precise. As already remarked, the long and lustrous wools are the typical English; being grown in Lincolnshire, Yorkshire, Nottinghamshire, Devonshire, &c., in fact in all those districts where the pasturage is rich and specially fitted for carrying a heavy sheep. It is claimed that the lustre upon the wool is a direct result of the environment, and that to take a Lincoln sheep into Norfolk means the loss of the lustre. This is partially true, but it is perhaps better to take a larger view and remember that the two influencing factors are race and environment: which is the more potent it is impossible to say. Attempts were made in the 18th century to develop a fine wool breed in England, George IV. importing a number of merino sheep from Spain. The discovery was soon made that it was impossible to maintain a breed of pure merinos in Great Britain, but the final outcome was by no means unsatisfactory. By crossing with the indigenous sheep a race of fairly fine woolled sheep was developed, of which the present day representative is the Southdown - a sheep which feeds naturally on the Downs of Sussex, &c., forming a marked contrast to the artificially turnip-fed Lincoln, Leicester, &c., sheep. Following the short, curly Southdown, but rather longer, come such as the Sussex, Oxford and Hampshire Down sheep; these are followed by such as the Shropshires and Shropshire crosses, Kent and Romney Marsh, until at last the chain from the Southdown to the Lincoln is completed. Of course there are several British wools not included in this chain. Scotch or black-face wool is long and rough, but well adapted for being spun into carpet yarns. Welsh wool has the peculiarity of early attaining its limit of shrinkage when washed, and hence is specially chosen for flannels. Shetland wool is of a soft nature specially suited for knitting yarns, while Cheviot wool - said to be a cross between merino sheep saved from the wreck of the Great Armada and the native Cheviot sheep - has made the reputation of the Scottish manufacturers for tweeds. North wool - wool from an animal of the Border Leicester and Cheviot breed - Ripon, Wensleydale and Teasdale wools are also specially noted as lustre wools, Ripon and Wensleydale wools being, by many judges, considered superior so far as lustre is concerned to Lincoln and Leicester. | Weight of Breed. Average Fleece. | Breed. | Weight of Average Fleece. |
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| Merino (Australian) | 6 lb | Southdown . | 6 lb | | Merino (South | | Lincoln. . | 12 lb | | American). . | 61 lb | Shetland . | 4 th | | Merino-Lincoln | 8-to lb | Cashmere | . 4 oz. Such remarkable advances have been made in the weights of fleeces carried by sheep of particular breeds that it is difficult to say if finality has been reached. The following list gives average weights: In 1885 the average weight of wool per sheep per year was about 5 lb, while 7 to 8 lb is now the average weight. Roughly speaking the weights of Australian fleeces are to-day about double as compared with 1885. The prevailing colour of sheep's wool is white, but there are races with black, brown, fawn, yellow and grey shades of wool. For manufacturing purposes generally white wool is, Physical of course, most valuable, but for the homespuns, which character- in earlier times absorbed the bulk of wool, natural istics of colours were in many cases used with good effect. In domestic spinning, knitting, and weaving, natural colours are still largely taken advantage of, as in the cases of rough yarns, Shetland knitted shawls, Highland tweeds, &c. As has already been indicated, the distinction between wool and hair lies chiefly in the great fineness, softness, and waved delicacy of woollen fibre, combined with a highly serrated surface. These peculiarities are precisely the characters which give wool its distinctive value as a textile fibre, the most distinctive characteristic of all being the serrated structure which specially belongs to wool and markedly aids the important property of felting, upon which many of its applications depend. The serrations of wool and the wavy structure it assumes are closely connected, those wools which have the greatest number of serrations being usually most finely waved in structure. The appearance presented by wool under the microscope is shown in figs. 1-6 (Plate). Under the influence of moisture and pressure, aided by alkalis or acids, masses of wool thoroughly mat together, by the mutual interlocking of the fibres. It is thus that the shrinking and thickening of woollen textures under washing is accounted for, the capacity of wool cloth for felting or fulling being due to this condition of the fibre, possibly along with a certain shrinkage of the true fibre mass. The serrations are most numerous, acute, pointed and distinct in fine merino wools, as many as 2800 per in. being counted in specimens of the finest Saxony wools. In the Leicester wool of England, on the other hand, which is a long bright staple, the serratures are not only much fewer in number, counting about 1800, but they are also less pronounced in character, so that the fibre presents a smoother, less waved character. In some inferior wools the serrations are not so many as 500 per in. A similar difference may be noted in the fineness of the fibres. The finest wool has a diameter of from 20 o o to o 0 o o in., whilst coarse Algerian wools may rise to a maximum diameter of about 2 in. Other distinguishing qualities of good wool consist in uniformity and strength of fibre with freedom from tender or weak portions in its length, a condition which not unfrequently arises from ill health in the sheep, or is due to violent climatic changes. In ill-bred wool there may also be found intermingled " kemps or dead hairs - straight, coarse, dull fibres which show conspicuously among the wool, and become even more prominent in the manufactured and dyed goods, as they will not take dye. Wool also possesses a softness of touch and an elasticity both in the raw and manufactured condition which distinguish it from all other fibres. In length of staple it varies very much, attaining in combing wools to a length of as much as 15 to 20 in. In dealing with wool from a practical point of view it must be recognized that it is by no means a simple body, but has a somewhat complex physical structure. Its composition in the raw state may be said to be threefold. character- Thus there is the wool-yolk - what may be termed a istics of natural impurity; the wool-fat, which is not only wool. present in the yolk but also permeates the fibre and seems to give it its plastic and soft handle; and the cell structure proper of the fibre. The natural impurity or wool-yolk is truly a skin product and is a protector of the wool-fibre rather than part of the true fibre substance. The wool-fat also may be regarded as independent of the true fibrous substance, but it is well to recognize that if the wool-fibre be entirely freed from the wool-fat it loses its plastic and elastic nature and is considerably damaged. In cleansing wool the true fibre mass may be disturbed and partially destroyed not only by dry but also by " wet " heat, and may be entirely disintegrated by means of alkalies, &c., with heat. The wool-fibre will almost free itself from the natural impurities - the yolk - in the presence of tepid water. This is taken advantage of in the various steeping machines placed on the market, which partially scour the wool by means of its own yolk - principally through the potash salts present. According to Hummel the composition of the average wool-yolk is as follows: Moisture Yolk . The potash salts are usually recovered from the wash-water products and a marked economy thereby effected. | Carbon . | 50.8 | | Hydrogen . | 7.2 | | Nitrogen . | 18.5 | | Oxygen | 21 2 | | Sulphur | 2.3 | | | 100 0 The natural wool-fat - popularly known as " lanoline " - may be partially got rid of in the steeping process, but it is almost invariably necessary to free the wool still further from it by actually scouring the wool on either the " emulsion " or " solvent " method, in either case the action being largely physical. As previously pointed out, however, all the wool-fat must not be taken away from the fibre, or the fibre will lose its " nature." According to Dr Bowman, the chemical composition of the cell structure of the average wool-fibre is: - It is said to be a most complex body of which the probable formula iS C42H157N5S015. If wool is burnt, it largely resolves itself into ammonia gas - whence it derives its characteristic odour - and carbon " beads " or " remains," which serve to distinguish wool from cotton, which, upon being burnt, does not smoulder but burns with a flash and leaves no beads For further particulars on the organic nature of the woolfibre see Fibres. The bulk of the wool of commerce comes into the market in the form of fleece wool, the product of a single year's growth, cut from the body of the living animal. The first and finest clip, called lambs' wool, may be taken from the young sheep at about the age of eight months. When the animal is not shorn till it attains the age of twelve or fourteen months the wool is known as hogg or hogget, and, like lambs' wool, is fine and tapers to a point. All subsequently cut fleeces are known as wether wool, and possess relatively somewhat less value than the first clip. Fleece wool as it comes into the market is " in the grease," that is, unwashed, and with all the dirt which gathers to the surface of the greasy wool present; or it is received as " washed " wool, the washing being done as a preliminary to the sheep-shearing, or, in some few cases, it is scoured and is consequently stated as " scoured. " Skin wool is that which is obtained from sheep which either die or are killed. Typical skin wool is that which has been removed by a sweating process. The worst type of skin wool - technically known as " slipe "--is removed from the skins by lime, which naturally affects the handle of the wool and renders it difficult to bring into a workable condition later. Mazamet in France is the great continental centre for skin wools. Where there is abundance of water and other conveniences it is the practice to wash or half-wash sheep previous to shearing, and Sheep such wool comes into the market as washed or half- washing. washed fleece. The surface of a fleece has usually a thick coating of dirt, and in the case of merino breeds the fleece surface is firmly caked together into solid masses, from the adhesion of dirt to the wool constantly moist with the exudation from the skin of the greasy yolk or " suint," so that in an unwashed very greasy fleece 30% of weight may represent dirt, and about 40% the greasy suint which lubricates the wool, while the pure wool is not more than one-third part of the whole. Where running streams exist, the sheep are penned by the side of the water, and taken one by one and held in the stream while they are washed, one man holding and the other washing. The operation is objectionable in many ways, as it pollutes the stream, and it dissipates no mean amount of potash salts, valuable for manure or for other chemical purposes. Sheep washing appliances are now largely employed, the arrangement consisting of a pen into which the sheep are driven and subjected to a strong spray of water either hot or cold, which soaks the fleece and softens the dirt. This done, they are caused to swim along a tank which narrows towards the exit, and just as they pass out of the pen they are caught and subjected to a strong douche of pure water. They should then be kept on grass land free from straw, sand, &c., so that the wool may be sheared free from vegetable matter, &c. After a few days the wool of a washed sheep is sufficiently dry for shearing or clipping. The relative advantages of shipping wool in the greasy or washed state have been fiercely debated. Although there are naturally exceptions, the superiority of greasy wool is now generally recognized. This is not only because the wool more fully retains its nature, but because it is more readily judged for " yield " and its spinning qualities are, perhaps, more readily estimated. | 75% clean wool. Type of Wool. Yield per cent of Clean Wool. |
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| Australian Merino.. . | 50% | | Cape | 48% | | South American Merino . | 45% | | New Zealand Cross-bred . | 75% | | South American Cross-bred | 75% | | English Southdown . | 80 | | Shropshire . | 80% | | „ Lincoln | 75% | | Mohair. ... . | 85% | | Alpaca | 85% The following list gives an idea of the yield in clean wool of the chief commercial varieties, from which it will be noted that roughly merino greasy wool yields about 50% clean wool and English about A skilful shearer will clip the fleece from a sheep in one unbroken continuous sheet, retaining the form and relative positions of the mass almost as if the creature had been skinned. In this Sheep unbroken condition each fleece is rolled up by itself and shearing. tied with its own wool, which greatly facilitates the sorting or stapling which all wool undergoes for the separation of the several qualities which make up the fleece. Mechanical shears have almost revolutionized the shearing industry, a good shearer shearing from 100 to 200 sheep per day. On the great Australian sheep stations wool classing is one of the most important operations, largely taking the place of sorting in the English wool trade. This is no doubt due to the wonderful Wool success which has attended the efforts of the Australian classing. sheep breeders to breed a sheep of uniform staple throughout. Thus the fleeces as taken from the sheep are skirted and trimmed on one table and then passed on to the classer, who places them in the 56's, 60's, 64's, 70's, 80's or 90's class according to their fineness, these numbers approximately indicating the worsted counts to which it is supposed they will spin. The shorter Australian wools not coming under any of these heads are classed as super-clothing, ordinary clothing, &c., being more suitable for the woollen industry. The art of sheep shearing, skirting, classing, packing and transporting has been brought up to a wonderful state of perfection in Australia, and the " get up " of the wool is usually much superior to the " get up " of the " home-clip." Of late there has been an outcry against the prevalence of vegetable matter in colonial wools, but it seems probable that with the adoption of a suitable woolpack, and the exercising of a little more care in sorting at the home end, this difficulty will be satisfactorily surmounted. Sorting or stapling was formerly a distinct industry, and to some extent it is so still, though frequently the work is done on the premises of the comber or spinner. Carding wools are Wool separated and classed differently from combing wools, and in dealing with fleeces from different breeds, the classification of the sorter varies. In the woollen trade short-staple wool is separated into qualities, known, in descending series from the finest to the most worthless, as picklock, prime, choice, super, head, seconds, abb and breech, and the proportions in which the higher and lower qualities are present are determined by the " class " of the fleece. In the worsted trade the classification goes, also in descending series, from fine, blue, neat, brown, breech, downright, seconds, to abb for English wools. The last three are short and not commonly used in the worsted trade. The greater proportion of good English long wool will be classified as blue, neat and brown; it is only in exceptional cases that more than from 5 to 8% is " fine " on the one hand, or of lower quality than breech on the other. Generally speaking, the best portion of a fleece is from the shoulders and side of the animal. The quality decreases towards the tail end of the sheep, the " britch " being frequently long, strong and irregular. The belly wool is short, worn and dirty, as is also the front of the throat, while on the head and shins the product is short, stiff and straight, more like hair than wool and is liable to contain grey hairs. The colonial wools come " classed," and consequently are only as a rule sorted into three or four qualities. Thus a 60's fleece may be sorted into 56's, ordinary 60's, super 60's and skirtings. | | PLATE. | | | The sorter works at a table or frame covered with wire netting through which dust and dirt fall as he handles the wool. Fleeces which have been hard packed in bales, especially if unwashed, go into, dense hard masses, which may be heated till the softening of the yolk and the swelling of the fibres make them pliable and easily opened up. When the fleece is spread out the stapler first divides it into two equal sides; then he picks away all straws, large burrs, and tarry fragments which are visible; and then with marvellous precision and certainty he picks out his separate qualities, throwing each lot into 4t024%Dirt. 3t024%. 12 ,,47% I Wool-fibre... 15 „ 7 2% Lamb, Hogg and Wether wool. FIG. I. - Mohair (X320). FIG. 2. - Leicester Wool (X320). FIG. 4. - Alpaca Wool Hair (X320). FIG. 5. - Down Wool (X320). Missing image Woolworstedandwoollenmanufactures-1.jpg FIG. 3. - NEW Zealand Cross-Bred Wool (X320). FIG. 6. - Australian Merino Wool (X320). Photomicrographs of the most representative hairs and wools used in the textile industries. XXVIII. 808. - .
its allotted receptacle. Sorting is very far removed from being a mere mechanical process of selecting and separating the wool from certain parts of the fleece, because in each individual fleece qualities and proportions differ, and it is only by long experience that a stapler is enabled, almost as it were by instinct, rightly to divide up his lots, so as to produce even qualities of raw material. Cleanliness is most essential if the wool sorter is to keep his health and not succumb to the dread disease known as " anthrax " or " wool-sorters' disease." Certain wools such as Persian, Van mohair, &c., are known to be very liable to carry the anthrax bacilli, and must be sorted under the conditions imposed by government for " dangerous wools." Ordinary or non-dangerous wools are perfectly harmless from this point of view. The washing which a fleece may have received on the live sheep is not sufficient for the ordinary purposes of the manufacturer. On the careful and complete manner in which scouring is effected much depends. The qualities of the fibre may be seriously injured by injudicious treatment, while, if the wool is imperfectly cleansed, it will dye unevenly, and the manufacturing operations will be more or less unsatisfactory. The water used for scouring should be soft and pure, both to save soap and still more because the insoluble lime soap formed in dissolving soap in hard water is deposited on the wool fibres and becomes so fixed that its removal is a matter of extreme difficulty. In former times stale urine was a favourite medium in which to scour wool; but that is now a thing of the past, and a specially prepared potash s soap is the detergent prin 36 cipally relied on. Excess of alkali has to be guarded against, since uncombined caustic acts energetically on the wool fibre - especially in the presence of heat - and is indeed a solvent of it. A soap solution of too great strength leaves the wool harsh and brittle, and the same detrimental result arises when the soapy solution is applied too hot. In former days, when the method of hand-scouring prevailed, the wool to be washed was placed with hot soap-sud in a large scouring " bowl " or vat, and two men with long poles kept stirring it gently about till the detergent loosened and separated the dirt and dissociated the grease. The wool was then lifted out and drained, after which it was rinsed in a current of clean water to remove the " scour " and then dried. These operations are now performed in scouring machines. Many firms now steep the wool previous to the true scouring operation, the object being to scour the wool with its own potash salts, to obtain wash-waters so fully charged with the potash salts that these salts, &c., may be readily extracted and put to some good use, and lastly to save the artificial scouring agent employed in the true scouring operation. The scouring of wool has passed through many vicissitudes during the past fifty years, but to-day the principle upon which all scouring machines are based is that wool naturally opens out in water. The mechanical arrangements of the machines are such as to ensure the passage of the wool without undue lifting and " stringing," to obviate the mixing of wool grease, sand, dirt, &c., once taken out of the wool with that wool again, to give time for the thorough action of the scouring agents, so that neither too strong a solution nor too great a heat be employed, and to allow of the ready cleansing of the machines so that there is no unnecessary waste of time. In England the recognized type of merino wool-washing machine is the fork-frame bowl. Three to five of these machines are employed. The " scour " is strongest and hottest in the first bowl (unless this is used as a " steeper ") as the wool at first is protected from the caustic by the wool-fat, &c., present. The last bowl is simply a rinsing bowl. With modern " nip rollers " botany wool is sufficiently dry to be passed on directly - say by pneumatic conveyers - to the carding. This the worsted spinner does, thereby saving time and money. The woollen spinner, however, may require the wool for blending, and so may require it dry and in a fit state for oiling. He, therefore, will employ one or other of the drying processes to be immediately described. For English and cross-bred wools more agitation in the scouring bath may be desirable. If so, the eccentric fork action machine is employed, in which the agitation of the bath is satisfactorily controlled by the setting of the forks which propel the wool forward. An average wool will be in the XXVIII. 26 a scouring liquor about eight minutes, the temperature will vary from 120 0 F. to 110 0 F., and the length of bath through which it will have passed will be from 48 to 60 ft. It is interesting to note that the " emulsion " method of wool scouring as described above is practically universal in England. In the United States of America the " solvent " method is largely in use, for the two points aimed at are quantity of production and cheapness. Quality is sacrificed to quantity and cheapness results from the ease with which the agent employed - say carbon disulphide - is recovered by volatilizing and condensing, thus being used over and over again. Botany wools should leave the wool-washing machine in a fit condition to be fed immediately on to the carder, provided that the first cylinders are clothed with galvanized wire. Cross-bred and English wool, however, require artificially drying. The more gently and uniformly the drying can be effected the better is the result attained; over-drying of wool has to be specially guarded against. By some manufacturers the wool from Wool the squeezing rollers is whizzed in a hydro-extractor, drying. which drives out so much of the moisture that the further drying is easily effected. The commonest way, however, of drying is to spread the wool as uniformly as possible over a framework of wire netting, under or over which is a range of steam-heated pipes. A fan blast blows air over these hot pipes, and the heated air passes up and is forced upwards through the layer of wool which rests on the netting or downwards, as the case may be. In this case, unless the wool is spread with great evenness, it gets unequally dried, and at points where the hot air escapes freely it may be much over-dried. A more rapid and uniform result may be obtained by the use of the mechanical wool drier, a close chamber divided into horizontal compartments, the floors of which have alternate fixed and movable bars. Under the chamber is a tubular heating apparatus, and a fan by which a powerful current of heated air is blown up the side of the chamber, and through all the shelves or compartments successively, either following or opposing the wool in its passage through the machine. The wool is introduced by a continuous feed at one side of the chamber; the strength of the blast carries it up and deposits it on the upper shelf, and by the action of the movable bars, which are worked by cranks, it is carried forward to the opposite end, whence it drops to the next lower shelf, and so on it travels till at the extremity of the lower shelf it passes out by the delivery lattice well and equally dried. Another drying machine in extensive use is what is known as the " Jumbo Dryer." This consists of a large revolving cylinder or churn which turns over the wool - as a churn turns butter - and owing to its inclination passes it from one end to the other. A hot air blast follows the wool through the machine. In this and in all drying machines it is more important to get the moisture laden air away from the wool than to develop a great heat. The dried wool may be in a partially matted condition. If so, it must be opened out and the whole material brought into a uniformly free and loose condition. This is effected in the Willey, T which consists of a large drum and three small cylinders mounted in an enclosed frame. The drum is armed with ranges of powerful hooked teeth or spikes, and is geared to rotate with great rapidity, making about 500 revolutions per minute. The smaller cylinders, called workers, are also provided with strong spikes; they are mounted over the drum and revolve more slowly in a direction contrary to the drum, the spikes of which just clear those of the workers. The wool is fed into the drum, which carries it round with great velocity; but, as it passes on, the locks are caught by the spikes of the workers, and in the contest for possessing the wool the matted locks are torn asunder till the whole wool is delivered in a light, free and disentangled condition. It is a debatable point as to whether willowing should precede scouring. Some scourers always willow prior to scouring, while others never subject the wool to this opera. tion, which is advantageous in some cases and not in others. For certain classes of wool, notably Buenos Aires, still another preparing operation is essential at this stage - that is, the removal of burrs or small persistently adherent seeds and other fragments of vegetable matter which remain in the wool. Two methods of effecting this - one chemical, the other mechanical - may be pursued. The chemical treatment consists in steeping the wool in a dilute solution of sulphuric acid (or other carbonizing agent), draining off the dilute acid by means of the hydro extractor, and then heat-drying in a temperature of about 250 0 F. The acid leaves the wool practically uninjured, but is concentrated on the more absorbent vegetable matter, and the high heat causes it to act so that the vegetable matter becomes completely carbonized. The burrs are then crushed and the wool 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 Scouring. Tail 7. - Qualities of Wool in a Lincoln Fleece. The numbers indicate the quality of wool taken from the respective sections of the fleece. Thus the finest quality - 44' s - is found on the shoulders, while the coarsest " britch " is found on the hind-quarters of the sheep. Missing image Woolworstedandwoollenmanufactures-2.jpg FIG. Missing image Woolworstedandwoollenmanufactures-3.jpg 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 a certain amount of wool adhering to them, by another rotating cylinder. With wools not too burry the worsted spinner largely depends upon burring rollers placed upon the first cylinder of the " carder," and possibly to one or other of the patent pulverizing processes applied further on in the card. In the latter process a complete pulverizing of the burrs is aimed at, this being effected by the introduction of specially constructed pulverizing rollers between the first doffer and the last swift of the carding engine. The processes hitherto described are common to merino, cross-bred or botany wools be they intended for woollen or worsted yarns. From this point, however, differentiation starts. Wool may now be manipulated with the idea of converting it into felt (q.v.), woollen or worsted fabrics. In a general way it may be said that woollen yarns are those made from short wools possessed of high felting qualities, which are prepared by the process of carding; whereby the fibres are as far as possible crossed and interlaced with each other, and that the carded-slivers, though perhaps hard spun on the mule frame, form a light fluffy yarn, which suits the conditions 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 parallel to each other; the spinning is usually effected on the frame, and the yarn is spun into a compact, smooth and level thread, which, when woven into cloth, is not necessarily 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 some worsteds made from short staple wool, carded as well as combed. Worsted yarn is now largely spun on the mule frame, while milling or felting is a process done in all degrees - woollen being sometimes not at all milled, while to some worsteds a certain milled finish is given. The fundamental distinction between the two rests in the crossing and interlacing of the fibres in preparing woollen yarn - an operation confined to this alone among all textiles, 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. To obtain a sliver which can be satisfactorily spun into a typical woollen thread woollen the following operations are yam necessary: willowing, oiling and blending, teasing, carding (two or three operations), condensing and roving. Spinning . upon the woollen mule completes the series of operations all of which are designed to lead up to the desired result. Of the foregoing operations the carding is perhaps the most important as it is certainly one of the most interesting. At the same time it must be fully realized that deficiencies in any one of these operations will result in bad work at every subsequent process. For example, let an unsatisfactory combination of materials be blended together and there will be trouble in both carding and spinning. The roving operation included above is not always necessary. In the old days, if a really fine thread were required, roving was absolutely necessary, as the carder could not turn off a sliver fine enough to be spun at one operation. To-day, however, with the " tape " condensers, such fine slivers can be turned off the condenser that there is no difficulty in spinning directly to the required count. In some few cases, however, it may be cheaper to rove than to condense fine; again, certain physical characteristics appertain to the roved thread, as distinct from the condensed thread, which may occasionally be of use to the cloth constructor. At the beginning of the 19th century woollen cloths were made of wool - some of them of the very finest wool obtainable. To-day woollen cloths are made from any and every kind of material, of which the following are the most important: noils (botany, cross-bred, English, alpaca and mohair), mungo, shoddy, extract, flocks, fud (short mill waste), cotton sweeping, silk waste, &c., &c.; in fact it is said that anything which has two ends to it can be incorporated into a woollen thread and cloth. It does not follow, however, that all woollen cloth is cheap and nasty. On the contrary the west of England still produces the finest woollen fabrics of really marvellous texture and beauty, and Batley, Dewsbury, &c., produce many fabrics which are certainly cheap and yet anything but nasty. The first essential for blending is that the materials to be blended should be fairly finely divided. This is effected by passing each material, if necessary, through the willow or through the " fearnaught " - a machine coming between the willow and card - prior to beginning the " blend-stack." Sometimes it may be that a blending of different colours of wools to obtain a definite " colour mixture " is necessary, more often it will be a blending of various materials, such as noils, mungo, cotton, &c., to obtain a cheap blend which may be spun into a satisfactory warp or weft yarn. The blender proceeds as follows: first a layer of No. material - say wool - is spread over the required area on the floor; it is then lightly oiled. A layer of No. 2 material - say noils - is now added to the first layer; then another layer of wool with rather more oiling; then No. 2, then No. i with still more oil until all the material is built up into layers in the stack. The stack is now beaten down sideways with sticks, and then the more or less mixed mass is passed through the willow and fearnaught still further to mix it prior to carding, where the true and really fine mixing takes place. After passing through the fearnaught the material is sheeted and left to " mellow," this no doubt consisting in the oil applied distributing itself throughout the material. If wool and cotton are blended together the wool must be oiled first, or the blend will not work to the greatest advantage. The oil may be best Gallipoli olive oil - which should not turn rancid - but there are many good oils - and unfortunately many bad oils - placed on the market at a reasonable rate which the really skilled judge may use to advantage. The percentage of oil varies from 2% to Io % - this remark applies both to the woollen and worsted trades - and there is no guide as to the amount required, saving and excepting experience, observation and common sense. Automatic oiling arrangements have been applied in the woollen trade with only a moderate amount of success, the sprinkling of the oil by means of a watering-can on the stack, made as described above, still being most in favour. The oil serves to lubricate the fibres, and to render them more plastic and consequently more workable, and to bind the fibrous mass together and thus prevent " fly " during the passage through the cards. Carding was originally effected by hand, two flat boards with con FIG. 8. - Sectional View of Carder; illustrating the principles of carding. Missing image Woolworstedandwoollenmanufactures-4.jpg Missing image Woolworstedandwoollenmanufactures-5.jpg Missing image Woolworstedandwoollenmanufactures-6.jpg venient handles, covered with teeth or card clothing, serving as a means of teasing out lock by lock, fibre by fibre, reversing root to tip and tip to root, so that a perfect mixing of the fibres re- Carding. sulted. It was but natural that, when an attempt was made to render the carding operation more mechanical, the operation should be converted into a continuous one through the adoption of rollers in place of flats. Flats combined with rollers still maintain their position in cotton carding, but in wool carding the pure roller card is employed. The factors of carding are size of rollers, speeds of rollers, inclination of teeth and density of card clothing. Probably no operation in the textile industries is so little understood as carding. Thus the long wool carder would think a man an idiot who suggested the running of the teeth of the various cylinders actually into one another, while the short mungo carder regularly carries out this idea, and so on. The underlying principle of carding, however, is shown in fig. 8, in which a sectional drawing of part of a card is given. The wool is carried into the machine on a travelling lattice and delivered to the feed rollers A, A', A" of which A and A" in turn are stripped by the licker-in B working at a greater speed point to smooth side. This in turn is stripped by the angle stripper C again working at a greater speed point to smooth side, which in its turn is stripped by the swift D - the " carrying-forward " and swiftest carding cylinder in the machine. The swift carries the wool forward past the stripper E - which as a matter of fact is stripped by the swift still working point to smooth side - into the slowly retreating teeth of the first worker F, which, being set a fair distance from the swift, just allows well laid-down wool to pass, but catches any projecting and uncarded staples. The worker in its turn is stripped by the stripper E', which in turn is stripped by the swift as already described. The passage of the wool forward through the 'machine depends upon its being carried past each worker in turn. Thus from beginning to end of a machine the workers are set closer and closer to the swift, so that the last worker only allows completely carded wool to pass it. Immediately on passing the last worker F' the wool is brushed up on the surface of the swift by the " fancy " G - as a rule the only cylinder whose teeth actually work into the teeth of the swift and the only cylinder with a greater surface speed than the swift. The swift then throws its brushed-up coating of wool into the slowly retreating teeth of the doffer H. which carries it forward until angle stripper C' strips the doffer, to be in its turn stripped by swift D' and so on. The speeds of the cylinders are in the first place obviously dependent upon the principle of carding adopted, the greater speed always stripping (save in the case of the fancy). As to whether the speed shall be obtained by actual revolutions or by a larger diameter of cylinder depends upon the nature of the wool to be carded (long or short), the part which each cylinder has to play in the card, and upon the question of wear of clothing and power consumed. As a rule the strippers are all driven from a smaller circumference of the swift to obtain conveniently the necessary reduction in speed, and the slowly revolving workers are chain driven from the doffer, which indirectly receives its motion from the swift. The principles involved in the relative inclinations of teeth are very apparent, but the principles involved in the relative densities of teeth on the respective cylinders are again much involved and little understood. A complete scribbler or first card engine consists of a breast, or small swift, and two swifts with the accompanying workers, strippers, fancies, doffers, &c. The wool is stripped from this card as a thin film by means of the doffing comb. This is usually weighed on to the next machine - whether intermediate or condenser - a given weight giving a definite count of condensed sliver. Should an intermediate be employed, there must be an automatic feed, taking the wool, as stripped from the last doffer of the intermediate, and feeding it perfectly evenly on to the feed sheet of the condenser. The condenser is usually a one-swifted card, the only difference in principle being that, whereas the sliver comes out of the scribbler or intermediate in one broad film, it is broken up into a number of small continuous slivers or films, each one of which will ultimately be drafted or drawn out and twisted into a more or less perfect thread. These slivers - which are delicate and pith-like in substance - are wound on to light bobbins, and these bobbins are placed on the mule for the final roving and spinning operations. There are many forms of condensing mechanisms such as the single-doffer, the doubledoffer and the tape-condensers, but their construction is too complex to be described here. Whatever the type may be, the result is that noted above, but it should be noted that the tape enables a much finer sliver to be taken from the card than is possible with either the singleor double-doffer condenser. The principles involved in mule spinning are comparatively simple, but the necessary machinery is very complex; indeed it is question able if a more ingenious machine than the mule exists. The pith-like slivers received from the card-loom must be attenuated until the correct count of yarn is obtained; they must be twisted while this attenuation or drafting is in process, otherwise they would at once break; and after being attenuated to the required fineness the requisite number of turns must be inserted. Great stress must be laid on the effects of what is termed the " drafting-twist " noted above; it is probably this simultaneous drafting and twisting which develops the most pronounced characteristics of the woollen yarn and cloth, and differentiates it entirely from the strengthens them and thus from beginning to end equalizes the thread. Upon the completion of drafting the spindles are thrown on to " double speed " to complete the twisting of the 72" of yarn just spun as rapidly as possible, the carriage being allowed to run inwards for a few inches, to allow for the take-up due to twisting. The mule now stops dead, backs-off the turns of yarn from the bottom of the spindle to the top, the faller H wire falls into position to guide the thread on to the spindle to form the required cop G, and the counterfaller I wire rises to maintain a nice tension on the yarn. The carriage now runs in, the spindles being revolved to wind up the yarn, and, in. conjunction with the guiding on of the faller wire, builds up a firm cop or spool, as the case may be. Woollen mules are made with several hundred spindles and of varying pitch to suit particular requirements. Thus if the mules are to follow a set of say three carders with a tape condenser, and are required to spin fine counts, the pitch of the spindles may be much finer than ordinary, but a greater number will be required to work up the sliver delivered by the set of machines. There are many other details which require careful consideration; the inclination of the spindles, for example, must be suited to the material to be spun. And when all the mechanical arrangements are perfect there is still the necessity of correct judgment as to the qualities of the blend in hand, for in this case perhaps more than in Copyright Statement
These files are public domain. Bibliography Information
Chisholm, Hugh, General Editor. Entry for 'Wool, Worsted and Woollen Manufactures'. 1911 Encyclopedia Britanica. https://www.studylight.org/encyclopedias/eng/bri/w/wool-worsted-and-woollen-manufactures.html. 1910.
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