Jacquard's Loom

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Jacquard's Loom

Punched cards, used today to provide data and instructions to computers, were invented in the late eighteenth century by French inventor Joseph-Marie Jacquard (17521834) and were used to automate the weaving industry in France.

Jacquard was born on July 7, 1752 in a small village near Lyon. Both his parents worked in the weaving trade. At the age of ten, he went to work as a drawboy with his father. Drawboys had the tedious job of maneuvering by hand the weighted cords that controlled the pattern in the weaving of silk fabrics. Jacquard later invented a mechanical device to replace the drawboys. He started working on it in 1790, but his efforts were interrupted by the French Revolution. He finally succeeded in presenting a new silk drawloom at the Paris Exhibition in 1801. He completed an automated loom with punched cards controlling the weaving of very complicated patterns in 1805.

How are threads woven into a piece of cloth? Some, the warp, run lengthwise; others, the woof, run crosswise. In the loom, each thread of the warp can be lifted by a hook connected to a rod. At each weaving step, a thread of the woof is carried crosswise. A pattern in the fabric is created by lifting the warp threads, changing the choice of threads to lift from step to step. The choice, originally made by hand, is obtained by touching the tips of all the rods to a card in which holes have been previously punched according to a program. If a rod finds a hole, the thread is lifted. At the next step, the card is changed. The holes may or may not be in the same order as before. If not, the weaving occurs in a different way. Jacquard butted the cards one after the other in a very long loop and put the loop on a drum rotating in tempo with the advance of the fabric, so that the preprogrammed pattern could be repeated at every cycle of the loop.

Jacquard's loom was not welcomed by the silk weavers, who were afraid of being replaced by this new machine. The weavers of Lyon expressed their anger by burning the new looms and even attacking Jacquard. Ultimately, the loom proved its usefulness and became generally accepted. By 1812 there were 11,000 in use in France.

The Jacquard loom was a technological breakthrough that earned its inventor a pension from French Emperor Napoleon Bonaparte as well as a gold medal and the Cross of the Legion of Honour. By 1834 there were 30,000 looms in use in Lyon alone, and they were widely used throughout Europe and England. Jacquard died on August 7, 1834, at the age of 82.

see also Babbage, Charles; Hollerith, Herman.

Ida M. Flynn

Bibliography

Spencer, Donald D. Great Men and Women of Computing. Oakmont Beach, FL: Camelot Publishing, 1996.