Long before computers, a French loom was already reading programs on punched cards.
In 1804 Joseph Marie Jacquard patented a loom attachment that wove complex patterns by reading a chain of punched cards. Change the cards and you changed the design. That idea, a machine following swappable instructions, led through Charles Babbage to the punched cards that fed computers until the 1980s.
Before Jacquard, weaving a figured fabric such as damask or brocade on a drawloom needed a second worker, the draw boy, to lift the right warp threads by hand for every pass of the shuttle. It was slow, and the complexity of a pattern was limited by what people could manage. Several French inventors had tried to automate this. In 1725 Basile Bouchon used a roll of punched paper; Jean-Baptiste Falcon switched to individual cards; Jacques Vaucanson built a mechanism around a perforated drum.
Jacquard combined and improved those ideas. Cards laced into a continuous chain passed over a square box, one card per row of the design. Where a card had a hole, a rod slid through and its hook was lifted, raising the linked warp threads; where there was no hole, the hook stayed down. The weaver no longer needed an assistant, and any pattern that could be punched could be woven.
The most astonishing product may be a prayer book woven entirely in silk in Lyon in 1886 and 1887, with 58 pages of text and illustrations at 160 threads per centimetre. One book historian estimates it required between 106,000 and 500,000 punched cards. It took two years and almost 50 trials to get right, and only about 50 or 60 copies were made.
The wider legacy was the idea itself. Charles Babbage knew Jacquard's looms and planned to feed programs to his Analytical Engine on punched cards. Herman Hollerith built a punched-card tabulating machine for the 1890 US census, and a whole data-processing industry, dominated at first by IBM, grew from it. Cards remained a standard way to load programs and data into computers until the mid-1980s. Today's Jacquard looms are computer-controlled, but they still bear his name.
Source: Wikipedia — Jacquard machine · Text summarised from Wikipedia (CC BY-SA 4.0)
