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An Encyclopedia of the History of Technology part 84 doc

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PART FIVE: TECHNOLOGY AND SOCIETY 812 Another type of vertical loom used in antiquity was the two-beam vertical loom. This had wooden uprights, about 2m high, standing vertically. At the top and near the bottom were two horizontal beams. One of these beams, usually the top, could be adjusted to tension the warp. To warp up this loom, the yarn was tied to a bar at the back, passed over the top beam, down the front of the loom, under the bottom beam and up to the bar, where its direction was reversed. This gave a pair of yarns at the front for forming the shed. Carpets are still knotted by hand on a similar sort of loom in eastern countries, but for weaving cloth it was limited because the shed could not be opened very wide so there was difficulty in passing the weft through. There is much uncertainty about the origins of the horizontal loom in the West. There is no mention of it in Roman literature and there are no pictorial representations earlier than the Middle Ages. It was probably used in China first and spread to Asia Minor during the third to fourth centuries AD. Its advantage lay in having plenty of space where multiple heddles or a draw-cord device could be arranged for weaving figured textiles. Yet textiles with very complex patterns can be woven on the simplest looms by the weaver himself selecting which warp threads are to be raised and which lowered. A sword stick is inserted to keep that shed open while the weft is passed through. Bedouin Arabs still weave strips of carpet in this way. Because it takes a very long time to select each pick, not only is it exceedingly painstaking, but it is almost impossible to repeat the pattern exactly. THE MIDDLE AGES Carding At some time during the Middle Ages, a preparatory process appeared for disentangling the mass of raw wool fibres. It was called carding from cardus, the Latin name for a type of thistle or teazle which has small hooks covering its seed heads. The teazle heads were mounted side by side on wooden frames. The carder had a pair, one in each hand, so that he could separate the fibres from each other by drawing one card across the other (see Figure 17.1). When the fibres had been sufficiently disentangled, they were transferred to one card from which they could all be taken off and made into a rough roll or sliver. Usually this was spun into the finished yarn, but often it was drawn out into a coarse, loose length, lightly twisted, called a roving, which was spun subsequently into the finished yarn. It is certain that by the 1730s, the natural teazle was being replaced by bent metal wires, mounted in rows on letter strips which were nailed to wooden boards (see p. 830). This gave not only a large carding area but also one that was covered more evenly with hooks or points which were stronger than the teazle heads. TEXTILES AND CLOTHING 813 Spinning wheels Winding silk may have led to the development of the charka in India some time before AD 750. A spindle was mounted horizontally on a post and the whorl converted into a pulley driven by a band passing round a very much larger wheel which was turned by hand. This type of spinning wheel seems to have reached the British Isles during the fourteenth century when it had become much stronger and was mounted on legs so the spinner stood to work it. It had various names, such as the Great wheel or Jersey wheel (see Figure 17.2). With the right hand, the spinner turned the large wheel which rotated the spindle very rapidly. The left hand held the wool and was drawn away from the spindle, paying out the fibres while the right hand turned the wheel to put in twist. The yarn was held at an angle to the spindle so that, after a few turns, the yarn wrapped itself round the spindle until it reached the end. With continued turning of the spindle, the last coil of yarn slipped over the end and twisted the fibres. When the left hand had been drawn away as far as the arm could reach, twisting continued until the necessary strength had been achieved. To wind the yarn on, the spindle had to be reversed, or backed off, to unwind the coils at the tip. Then the left hand brought the yarn to a right angle with the spindle and guided it to form a nicely shaped cop or conical ball of thread, as the right hand was turning the wheel in the original direction again. Thus spinning with the great wheel was a multi-stage process, consisting of spinning, reversing, winding on and spinning again. Flax, wool and cotton could all be spun on this wheel and, Figure 17.1: The principles of carding by hand. Drawing by Richard Hills. PART FIVE: TECHNOLOGY AND SOCIETY 814 while the art could be learnt quickly, great skill was required to produce fine yarn with the same consistency throughout its length. Another type of spinning wheel, often called the Saxony wheel, flax wheel or flyer wheel, appeared soon after AD 1400. A large wheel drove the spindle to which was attached the flyer, a crosspiece with arms (see Figure 17.3). The wool passed through a hole in the end of the spindle so that it was twisted as the spindle was rotated by the whorl pulley. On the shank of the spindle was a bobbin with a pulley driven by a second band from the large wheel. The arms of the flyer guided the wool from the hole in the tip of the spindle to a position at the side of the bobbin. As the bobbin and spindle rotated at different speeds, because their pulleys were of different diameters, the wool was pulled through the hole and Figure 17.2: Stages of spinning on the Great wheel. Drawing by Richard Hills Figure 17.3: Spinning with flyer and bobbin on the Saxony or flax wheel. Drawing by Richard Hills. TEXTILES AND CLOTHING 815 wound on to the bobbin. In this way, twisting and winding on were combined into a single, continuous process. Soon a crank and foot pedal were fitted to drive the large wheel, leaving both hands free to pull out and control the fibres. This wheel was more suitable for spinning the longer fibres of flax and wool. It is not known whether it was the silk or the other textile industries which pioneered the flyer. In the other industries, the yarn was twisted as it was wound on to the bobbin. In the silk industry, the reverse happened. After the initial reeling of silk from the cocoons, the necessary number of filaments to make the final thread were unreeled and wound together on a bobbin. This was placed vertically in a frame with a spindle and flyer. There was a reel above which was turned to pull the silk off the bobbin while the spindle and flyer were rotated to put in twist. The weight of the bobbin resting on its ledge was sufficient to give enough drag to prevent it rotating at the same speed as the spindle and so the silk was twisted as it was pulled off the bobbin. Waterpowered silk throwing mills had appeared in Italy by 1500; Leonardo da Vinci drew a picture of a flyer and bobbin which had an automatic traverse to distribute the yarn evenly. Weaving The Middle Ages also saw great strides in the improvement of weaving techniques. In the thirteenth century the city of Winchester in Hampshire had two guilds of weavers, one for the vertical loom and one for the horizontal. Gradually the vertical loom disappeared from Britain because weaving on it was too slow. For example, a reed could not be used on the vertical loom. A reed was made from thin vertical strips of cane, spaced with slots between them rather like a comb but bound with strips of wood along the top and bottom. Pairs of warp threads passed through the slots so that not only was the warp kept evenly spaced to the correct width but the reed could be used to beat up the weft. Weaving was speeded up and the quality of the cloth improved. Behind the reed on a horizontal loom could be placed heddle frames which controlled the lifting of the warp. The frames were raised by foot pedals, which was not feasible on the vertical loom, and this left both hands free to throw and catch the shuttle. On a horizontal loom it was possible to fit in many more heddles and still give them sufficient lift to open a reasonable shed, which made it possible to weave more complex patterns. Still finer patterns could be woven by using a draw boy system (Figure 17.4). While a complex pattern could be selected by hand, a method of repeating this across the width and along the length of the cloth had to be devised so that the same pattern would appear time and again. To repeat a pattern across the width of the cloth, the appropriate warp threads could all be joined to a vertical leash, or lingo, so that by lifting this, all the others would be lifted too. If the pattern is based on 200 ends, then the leashes of numbers 1, 201, 401, 601, etc. will be joined together. PART FIVE: TECHNOLOGY AND SOCIETY 816 To repeat the pattern along the length, the identical warp threads must to lifted at the appropriate pick. All the vertical leashes for that pick were pulled to one side and, on the draw boy loom, a piece of string looped round them. The same was done for the next pick and similarly to the end of the pattern. A boy (hence the term draw boy loom) sat above the warp in the top of the loom. When he had sorted out the vertical leashes in the first loop of string, he wrapped them round a forked piece of wood which he twisted to raise the warp threads to form the shed. While he was sorting out leashes in the next loop, the weaver threw his shuttle and beat up the weft. It was possible to combine the draw boy system with a set of heddles which made weaving a little quicker. Draw boy looms were still being used to weave the finest cloth of gold at Isfahan in Iran at least until the fall of the Shah in 1975. Fulling Woollen cloth must be washed to remove grease and dirt, and this can be done at the same time as it is fulled. The tension in the warp threads during weaving will prevent the cloth being woven very tightly so, to make it more compact Figure 17.4: Draw boy loom. The weaver is sitting on the left while, in this case, the drawboy is standing beside the loom. TEXTILES AND CLOTHING 817 and to thicken it, advantage is taken of the felting characteristic of wool. The primitive way of fulling was to soak the cloth in a solution of fuller’s earth (an alkali) and pummel it with the feet. This was the origin of the ceilidh in the Scottish Highlands and Western Isles, when the women used to sit round in a circle with the cloth on the floor in the middle. While they pummelled it with their feet, it was a convenient time for gossip. It is also the origin of the place names Wauk (or Walk) Mill in England and Pandy in Wales. A mechanized way of fulling was available from the eleventh century on the Continent. The first record of fulling mills in England was in 1185 when two are mentioned, one in the Cotswolds and one in Yorkshire. A waterwheel turned a shaft with cams or tappets on it which lifted a pair of hammers alternately. The hammer heads pounded the cloth placed in a trough. The angle and slope of the heads ensured that the cloth rotated, to treat it equally throughout its length. The fulling mill was the first application of power to any textile process. In England it caused a shift of the industry out of the towns, with their well-established and restrictive guilds, into the hilly country where streams abounded and where flocks of sheep flourished and from the lowland east to the upland west. It also gave English textile producers a competitive edge over their rivals in Flanders, so it became more profitable to spin and weave cloth locally rather than to export the raw wool. The waterpowered fulling mill helped to give rise to the famous broadcloth industry in England. Two weavers worked at the broadcloth looms because they were too wide for one person to throw the shuttle through and catch it at the other side of the cloth. This cloth was finished by fulling, drying, stretching, raising, shearing and setting. Some fulling stocks remained in use to within the last decade. However, in 1833, John Dyer of Trowbridge patented the milling machine. The cloth is sewn up into a continuous length and the selvedges may be sewn together so that it becomes a long tube. The bulk of the cloth sits in the bottom of the machine where fuller’s earth and water can be fed in. A pair of rollers pulls the cloth out of the liquid and squashes it into a tapering spout. Some air will be trapped inside the sewn-up cloth and this will form a bubble in front of the rollers so that the cloth is opened up and then squeezed in a fresh place as it passes through. Fulling made the cloth more compact at the expense of shrinking it. To bring it back to a standard size, it was stretched and dried on a tenter frame which consisted of two unequal pairs of bars, two the length and two the width of the cloth. Each bar had tenter hooks nailed regularly along it. One end bar and the upper side bar were fixed. The ends of the cloth were hooked on to the end bars and stretched out by pulling on the movable one. The top edge was hooked on to the fixed long bar and the bottom on to the lower one which could be pulled down in to a slot and pegged. In this way the cloth could be stretched out taut to its finished size as it was dried (hence the term ‘on tenter hooks’). Hanging cloth out on tenter frames would take too long for modern production. Today a stenter is used. The tenter hooks are mounted on grippers PART FIVE: TECHNOLOGY AND SOCIETY 818 which form a pair of continuous chains. The grippers close automatically on either side of the cloth as it is fed in. Guides push the two chains of grippers away from each other until they have stretched the cloth to the correct width. They then take the cloth through a drying section heated by steam pipes. At the far end, the grippers are released and pass back under the stenter while the cloth is rolled up. A blanket has a raised surface or nap on which the wool fibres have been pulled out of the weave deliberately. At first raising was done by hand by pulling teazles mounted on wooden frames across the surface of the cloth. Gig mills, in which the teazles were mounted on rollers turned by hand or by water power, had made their appearance by the fifteenth century. Although today wire hooks, similar to card clothing, are used, teazles were long preferred for the highest quality woollen cloths and were used until the 1970s in some mills. To give a smooth surface to cloth such as the old broadcloth, the nap was then sheared off. Hand-operated shears of enormous size cut the loose fibres while the cloth was laid over a curved table-top. It required great skill and delicacy to achieve a smooth finish. Various attempts were made to mechanize the process by placing several pairs of shears in a frame and operating them by cranks, but this was not successful. A rotary shearing machine was first patented in England in 1794 by the American Samuel Dore, but again it was not successful. In 1815, J.Lewis of Brimscombe near Stroud, Gloucestershire, patented a rotary shearing machine with cutters that were forerunners of the cylinder type of grass mowing machine used today. The cloth was moved underneath the blades which could be of the same width, so only one operation was needed for each side. By 1830 hand shearing was extinct. THE SEVENTEENTH AND EARLY EIGHTEENTH CENTURIES Knitting Non-woven fabric can be made by taking a yarn and looping it into a series of interlocking stitches so that there is no separate warp and weft. Crocheting with a single hooked needle probably preceded knitting with a pair of pointed needles. Knitting may have been a Northern European, possibly Scandinavian, invention, but archaeological evidence has so far thrown little light on this subject. Certainly we know that knitting with needles had appeared in Britain by the fifteenth century. This looped fabric has much greater elasticity than a woven one, so that it moulds much more readily to the shape of the human body and is therefore particularly useful for closely fitting garments such as caps, socks and stockings, vests and pullovers. One inherent problem is that a dropped loop or broken thread can result in the whole garment unravelling. TEXTILES AND CLOTHING 819 The common way of hand knitting has never been mechanized. Skilled knitters can follow very complicated and beautiful patterns such as the multicoloured Fair Isle designs. Another method of knitting, peg knitting, formerly very popular, has almost died out except as a child’s toy in the form of headless nails driven into the end of a cotton reel. Loops are formed round the nails or pegs and then the yarn is wound round. The first loops are drawn over the yarn, over the tops of the pegs and then dropped into the centre hole or slot where the rest of the fabric hangs, leaving the next set of loops on the pegs. Sometimes the loops or stitches are lifted by a hooked needle. These rows of pegs may have given the Revd William Lee of Claverton, Nottinghamshire, the inspiration for the knitting machine he invented in 1589. It was a remarkably complex machine, needing at least seven or eight operations to make one row of stitches, and it is surprising that it succeeded as well as it did. A row of needles is placed horizontally and the last row of stitches is looped round their shanks with the fabric hanging below them. The needles are made from springy steel drawn out into a fine point. The point is bent back to form a hook that almost touches the shank of the needle. Normally these bearded needles are left open, but they can be closed by pressing the point into a small hollow ground in the shank. The knitter lays a shoot of yarn across the shanks of the needles in front of the first loops. Between each needle is a specially shaped piece of flat metal called a sinker. By using a foot pedal, a slurcock is drawn across the frame and causes the sinkers to push the yarn into loops over the needles. Next the sinkers push these loops forward under the points of the needles into the hooks at their heads. A presser bar is brought down to close the needle beards. The sinkers are raised so that a different part of them can be brought forward to push the first set of loops over the tops of the needle points and over the ends of the needle hooks as the presser bar is released. The arch of the sinkers draws the loops left in the needle hooks, and now part of the knitting, back on to the shanks ready for the next shoot of yarn. Finally the sinkers are raised again. Although complex, these bearded needles could be made finer than later types, so framework knitting has continued to be a commercial proposition up to the present day. Flat strips only could be knitted on these frames, but the width could be altered by casting on or off stitches. Therefore, stockings made on these frames had to be sewn up by hand. The other disadvantage of the original machine was that it could knit only plain stitch, which did not have the necessary flexibility for stockings or socks. In 1758, Jedediah Strutt of Derby developed the Derby rib frame, which could be attached to the front of an ordinary frame. On it, vertical needles could be inserted between the horizontal ones to reverse every other stitch and so create a ribbed fabric. The fortune he made with this invention helped him finance Arkwright’s spinning machine (see p. 827). The idea was extended further so that loops could be PART FIVE: TECHNOLOGY AND SOCIETY 820 moved from one needle to another, thus creating a pattern of holes in the fabric. In this way, a sort of lace could be made, or openwork shawls. Later a way was found of knitting three or four pieces side by side at the same time, and by 1800 the stocking frame had been developed to the limits of its versatility, being able to knit forty distinct types of fabric. To operate these frames was hard physical labour, so they were normally worked by men. Although very complicated, even the early ones soon achieved a speed of over 600 loops per minute, six times faster than knitting by hand, while later, silk stockings were being produced at the rate of 1500 loops per minute. Braiding On May Day, it was the custom to set up a maypole on the village green. Children were separated into two groups to dance round it in opposite directions, each child holding a ribbon attached to the top of the pole, and they wove in and out of those coming towards them. Eventually the pole was wrapped up in a braid. In commercial braiding, the children are replaced by bobbins with thread wound on them. The maypole can be replaced by a rope or by the centre core of an electric cable which is covered with a smooth outer sheathing of braid. A shoelace may be a type of braid with no centre core. Sometimes the bobbins do not make a complete circle but are turned back at one point. This gives a flat braid for ribbons and red tape or candle wicks. The Japanese developed the technique of braiding to a fine art for making multicoloured ceremonial cords. In 1748, a ‘maypole’ braiding machine was developed in Manchester. The tracks of the bobbins were pairs of semicircles and the bobbins had to be directed on their proper courses by deflectors. These machines could be turned by hand or by power. On later versions the tracks were lozenge-shaped and the bobbins were mounted on elongated slippers which could pass across the acute junction crossovers without any deflectors. Braid is still made on this type of machine today. Early mechanized weaving A loom on which more than one ribbon could be woven at once may have been invented by Anton Moller in Danzig in 1586. There was great opposition to it, both there and a little later in Holland when it appeared in that country. It arrived in England from the Low Countries, hence the name Dutch loom, and was being used in London by 1616 and Lancashire by 1680. At first only four to six ribbons could be woven at the same time, but this was improved to twenty by 1621 and eventually fifty and more. The shuttles were longer than TEXTILES AND CLOTHING 821 the width of the ribbon and on the early looms they were knocked through the shed by pegs fitted on to a sliding bar. Later the shuttles incorporated a rack, and pinions on the shuttle race, or slay, drove the shuttles through their sheds. In Switzerland, in 1730, means were devised for driving these looms by power, which was prohibited. An attempt to set up a waterpowered manufactory in Manchester in 1765 by a Mr Gartside also failed because one person was still needed to tend each loom in case any threads broke and to change the shuttle when the weft ran out. In 1787, Thomas Gorton ordered a 10.5kw (14hp) steam engine from Boulton and Watt (see Chapter 5) to drive his smallware factory at Cuckney, Nottinghamshire, which had 56 weaving frames as well as a room full of spinning machinery. In 1791, Richard Gorton patented a power loom which was weaving fabrics of fairly narrow width. Narrow fabric looms on these principles are still used today, particularly when fitted with a Jacquard harness (see p. 823) for weaving nametapes or labels. Ribbons with a simple pattern are being produced on looms where the shuttles have been replaced by needles. The needle pokes the weft through the warp and another catches the loop to complete the stitch, doubling the weft. The speed of production is of course very many times faster than on the old looms. The flying shuttle It is quite possible that John Kay of Bury, Lancashire, saw narrow fabric looms at work and from them derived his idea of the flying shuttle which he patented in 1733. Before this invention, the weaver had to pass the shuttle through the shed by hand, so the width of the cloth was limited to the distance he could reach. When he had passed the shuttle through, he had to change the position of his hands to beat up the weft with the reed. For broadcloth, two men were necessary to throw the shuttle to each other. The reed was mounted in a frame called the slay. Kay’s shuttle ran along a ledge or race on the slay in front of the reed into a box at either end. It had wheels to lessen the friction. The weaver’s right hand held a stick, the picking peg, to which were attached cords to pickers sliding inside the boxes. A jerk of the picking peg flicked the shuttle out of one box and sent it across the loom into the one on the other side. The left hand held the centre of the slay and beat up the weft with the reed once the shuttle had passed through. Not only did the weaver not have to change the position of his hands after each pick, which increased the speed of weaving, but also one person could weave much wider pieces. At first the flying shuttle was unpopular because workers were afraid that they would lose their jobs since it speeded up production. Also, it probably needed many minor modifications to make it work satisfactorily. For example, the race must be set at a slight acute angle to the reed or the shuttle will fall off, and the shuttle must be shaped to that angle. The wheels are positioned so that the shuttle . inside the boxes. A jerk of the picking peg flicked the shuttle out of one box and sent it across the loom into the one on the other side. The left hand held the centre of the slay and beat up the. to push the first set of loops over the tops of the needle points and over the ends of the needle hooks as the presser bar is released. The arch of the sinkers draws the loops left in the needle. by the whorl pulley. On the shank of the spindle was a bobbin with a pulley driven by a second band from the large wheel. The arms of the flyer guided the wool from the hole in the tip of the

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