Jacquard Loom

The Problem Jacquard Solved

Figured weaving — brocade, damask and other cloth where a pattern is built into the weave itself — was once among the most labor-intensive work in textiles. On a drawloom, producing one row of pattern required a second worker, the drawboy, to lift the correct combination of warp threads by pulling cords in sequence, while the weaver threw the shuttle. The work was slow, the errors were costly, and the pattern lived in a tangle of cords that only specialists could set up. Joseph Marie Jacquard's invention of 1801 attacked exactly that bottleneck: a head mounted on the loom that reads instructions mechanically, lifts the threads itself, and lets one weaver produce figured cloth that had previously required two skilled people and far more time.

The reading mechanism is a chain of pasteboard cards, each punched with holes and laced to the next in sequence. As the loom works, each card in turn is pressed against a bank of spring-loaded rods and hooks. Where a hole is punched, a rod passes through and its hook lifts the corresponding warp threads; where the card is solid, the rod is pushed back and those threads stay down. One card governs one pass of the weft, so a design of any length is simply a longer chain of cards, and changing the pattern means changing the chain. The pattern is thus stored outside the loom, in durable, copyable, sellable form — a library of designs could be kept as card chains and mounted as orders required.

Cards, Cloth and Computing

The consequences ran in two directions. In textiles, the Jacquard head spread through the silk mills of Lyon and then the world's weaving industry, attaching to hand looms first and power looms later, and it made richly figured fabrics dramatically cheaper and more consistent. The word jacquard passed from the machine to the cloth itself: a jacquard fabric is one whose pattern is woven in under individual warp-thread control, as opposed to a pattern printed on the surface, and modern jacquard looms, now driven electronically rather than by cards, still work on Jacquard's principle of selecting each warp end for each pick.

Beyond textiles, the punched card became one of the ancestors of the stored program. A pattern existed as holes or no-holes — information a machine could read and act on — and nineteenth-century inventors of calculating engines adopted punched cards for data and instructions, a lineage that ran through tabulating machines into twentieth-century computing. Weavers' card cutters, who punched designs square by square from a drawn pattern much as a programmer encodes instructions, are often described as among the first people to write machine code for a living. The Jacquard loom entry therefore belongs in a fashion dictionary twice over: for the figured fabrics it still produces, and for the idea, first proven at a loom, that a chain of punched cards can tell a machine how to make something beautiful.