Looms
The weaving of thread into cloth has been practiced for many thousands of years. As it is today, woven fabric was created by criss-crossing threads over and over again to form a tight mesh. Fairly early on, devices were constructed to make the task of weaving easier. One of the most primitive was called a peg loom or ground loom, and was used around 5,OOO b.c..
The ground loom consisted of two pegs driven into the ground, between which wooden bars were mounted. Long threads were hung over the wooden bars. The weaver sat in a shallow pit, weaving the cross-thread through the long threads. Later ground looms allowed the weaver to operate mechanisms by foot. Though this system was very crude, the quality of the fabric ultimately depended upon the skill of the weaver: an experienced weaver could produce beautiful tapestries on even the simplest of looms.
Since the creation of these first devices, the loom has evolved into one of the most complex machines in the world. Still, every loom, no matter how intricately constructed, is based on the same fundamental design. In woven fabric, there are two kinds of thread: the strong vertical warp thread and the weaker horizontal weft thread. In order for the fabric to mesh, the weft thread must be passed through the warp in an over-and-under fashion. Originally this was done by hand, but as loom technology improved mechanisms were built to lift every other warp thread, creating an opening called a shed through which the weft thread passed. First the even-numbered threads were lifted and the weft was passed through the shed. Then the even-numbered threads were lowered, the odd-numbered threads lifted, and the weft was passed through the other way. As each weft passage was completed the thread would be pushed, or beaten, against the cloth with a comb, creating a tightly woven fabric.
The first true frame looms were probably inspired by the silk weaving machines of China and India. These machines were equipped with foot pedals to lift the warp threads, leaving both of the weaver's hands free to pass and beat the weft thread. From this design came the vertical loom, a tall pair of vertical bars over which the warp threads were hung and kept taught by weights. This apparatus was soon found to be more efficient when laid flat, thus creating the horizontal loom, used as far back as ancient Egypt.
The horizontal loom was further improved by the addition of two devices: the heddle and the shuttle. The heddle was a foot-controlled bar that could lift an entire row of warp threads, creating a shed that extended from one side of the cloth to the other. The shuttle was a thin wooden slat upon which the weft thread was mounted. To weave the fabric, the shuttle was thrown through the shed and caught at the other side; the weaver would then beat down the weft, lift the other half of the warp threads, and throw the shuttle back through the shed. Later shuttles had spindles or bobbins built in, so that the weft would unwind behind it.
The heddle and shuttle were elegantly combined in the warping frame loom, invented by Frenchman Claude Dangon in 16O6. By the early l7OOs devices were added that could lift individual warp threads, allowing for the weaving of complex patterns and textures into the cloth. In 1728 another Frenchman, Falcon, suggested the use of perforated cards to "store" the cloth patterns; this idea would not be full explored for another seventy-five years.
The advancement of loom technology was not universally welcomed; on the contrary, each new invention was commonly received with fear and hostility, particularly on the part of the hand-weavers who saw themselves becoming rapidly obsolete. Often, the increasing use of weaving machines throughout the eighteenth and nineteenth centuries is identified with the beginnings of social unrest-particularly between the lower and upper classes. This is because weaving machines were the first mechanical devices to effectively replace large numbers of skilled workers. The word "sabotage" probably originates from these conflicts, for workers had been accused of throwing heavy shoes called sabots into the workings of the machines, destroying them.
The reaction to John Kay's (1704-1764) invention of the flying shuttle typifies the reception of loom technology by the hand-weavers. Kay had noticed that the primary drawback to the hand-thrown shuttle was that the width of the cloth could not be greater than the weaver's reach[frac34]for wider cloth, two weavers had to be employed to throw the shuttle back and forth. Kay designed a wheeled shuttle that ran along a ledge called the slay. To propel the flying shuttle through the shed, the weaver simply had to pull a cord. This system allowed a single man to weave broadcloth and still keep one hand free to manipulate the thread. Though Kay's invention effectively began the British Industrial Revolution by dramatically speeding the production of woven fabrics, he was the target of violence by local workers. He fled to France in 1747, where he died in poverty.
Often, the increasing use of weaving machines throughout the eighteenth and nineteenth centuries is identified with the beginnings of social unrest-particularly between the lower and upper classes. This is because weaving machines were the first mechanical devices to effectively replace large numbers of skilled workers. The word "sabotage" probably originates from these conflicts, for workers had been accused of throwing heavy shoes called sabots into the workings of the machines, destroying them.
The next step in the evolution of the loom came in 1706 when Edmund Cartwright constructed the first mechanical loom. This device is reputed to have been inspired by the mechanical water frame spinning machines of Richard Arkwright, which Cartwright had observed some years earlier. The mechanical loom almost completely automated the weaving process; now the only manual task was feeding thread into the machine. In 1791 Cartwright's mill was burned to the ground. His patents disputed in court by handweavers, Cartwright, too, died penniless.
In l8Ol, the French inventor Joseph-Marie Jacquard completed his patterning loom. This was a direct descendant of Falcon's design, using punched cards to control the lifting of certain warp threads. He received a gold medal and a pension of several thousand francs for his invention. In addition, the punched-card method for storing patterns was copied by the English scientist Charles Babbage, who planned to use similar cards in his steam-powered adding machine. Though Babbage's "analytical engine" was never constructed, it became the model for early computers-- most of which also used punched cards as a storage medium.
Inventors across Western Europe were busy designing looms that could be powered by water or steam. In 1822, Englishman Richard Roberts succeeded in developing a completely automatic loom; though, at first, it was able to weave only plain cloth, improvements were soon made that allowed for the weaving of complicated patterns. By the late 1800s, English-born mechanic J. H. Northrop constructed a power loom that did not need to be refilled when the weft ran out. Not only did this speed the weaving process, it also eliminated a lung affliction suffered by many loom workers who, as they sucked the weft thread through the shuttle, would inhale fabric dust. American, Erastus Bigelow, developed a power loom for the weaving of carpets, paving the way for wall-to-wall home and office carpets.
Most modern factory looms are based upon the inventions of Northrop and Bigelow. Today's looms only vaguely resemble those used even one hundred years ago. The use of a shuttle has been virtually eliminated; instead, weaving machines use pairs of gripping rapiers to push and pull the weft through. Other systems use spring-guns to fire the thread through the shed. More modern designs use jets of air or water; such machines can thread more than 1,500 wefts each minute.
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