Jacquard machine: How Punched Cards Directed the Weave
The Jacquard machine used punched cards to control textile weaving patterns. Fitted to a loom, the device simplified the production of complex designs such as brocade, damask, and matelasse. Its cards were laced together into a continuous sequence, with multiple rows of holes punched into each card. A complete card corresponded to a row of the design. Joseph Marie Jacquard patented the machine in 1804, building on earlier work by Basile Bouchon, Jean Baptiste Falcon, and Jacques Vaucanson. The holes belonged to a system for directing weaving long before punched cards became familiar tools for electronic computers. The finished pattern began with a sequence of physical instructions.
Before this mechanism, figured designs were traditionally made on a drawloom. A second operator, the draw boy, manually selected the heddles holding the warp ends that needed to be pulled up. This work was slow and labor-intensive, and practical constraints limited the pattern's complexity. Bouchon's improvement in 1725 used a perforated paper band. The continuous roll was punched by hand in sections representing a lash or tread, and its length depended on the number of shots in each pattern repeat. Jacquard later used Falcon's individual pasteboard cards and square prism, replacing Vaucanson's perforated barrel. His arrangement also increased the figuring capacity through additional rows of needles and uprights.
The Jacquard machine presented its instructions through a moving card chain. Each quarter rotation brought a new card to the head, representing a row or pick of the shuttle carrying the weft. The box pressed the card against control rods. Where a hole existed, a rod could pass through without moving; where the card had no hole, the rod was pushed to the left. Each rod acted on a hook. A pushed rod displaced its hook, while a rod that remained still left its hook in position for the next movement.
A beam then rose beneath the hooks. Hooks still in their resting positions were lifted; those displaced to the left stayed down. Each hook could carry multiple cords, with each cord passing through a guide and connecting to a heddle and return weight. The heddles raised the warp, opening the shed through which the shuttle carried the weft. A head with 400 hooks could have four threads connected to each hook, making a fabric 1600 warp ends wide with four repeats across it. Greater capacity, or multiple machines, permitted fewer repeats and larger designs across the width of the loom. The card's decisions thus reached individual groups of threads.
Using a Jacquard machine also involved commercial choices. Greater warp control generally meant greater expense, and a factory could use a dobby mechanism when its designs allowed it. Mechanical Jacquards cost more to maintain because they were complex, needed highly skilled operators, and required expensive systems for preparing designs. They could also produce more faults than dobby or cam shedding. Changing a design meant changing the continuous chain of cards, adding downtime and favoring larger production batches. Threading brought another demanding task: many looms were threaded only once, with later warps tied to the existing warp by a knotting robot that connected each new thread individually.
Electronic controls changed the practical balance. Bonas Textile Machinery NV launched the first successful electronic Jacquard at ITMA Milan in 1983. Modern capacity can extend to more than 10,000 warp ends under single-end control, removing the need for repeats and symmetrical designs. Computer-controlled equipment also reduces the downtime associated with changing punchcards, allowing smaller batches. The Jacquard machine still carries an expense tradeoff: electronic equipment may be unnecessary for a factory making large batches of smaller designs. Larger machines with single-end control are especially expensive and need substantial versatility or specialized designs to justify them. The choice depends on what the factory needs to weave.
Some woven objects show how elaborate card-directed work could become. A silk portrait of Jacquard required 24,000 punched cards in 1839; Charles Babbage owned one. A woven silk prayer book offered another striking application. Its 58 pages used black and gray thread, with elaborate borders, text, and pictures of saints. An estimated 106,000 to 500,000 punchcards encoded those pages. Designed by R. P. J. Hervier, woven by J. A. Henry, and published by A. Roux, the book was issued in Lyon in 1886 and 1887. Production took two years and almost 50 trials.
The computing connection developed through changing uses of cards. Babbage planned to store programs on cards for his Analytical Engine. Herman Hollerith later used punched cards to store information for a tabulating machine employed in the 1890 United States census. A data-processing industry followed in the first half of the twentieth century, initially dominated by IBM; its cards held data while plugboards handled programming. The 1944 Harvard Mark I received program instructions from punched paper tape. Later computers ran programs from faster memory, while cards remained a common way to load those programs. Punched cards continued in computing into the 1990s in some uses.