Jacquard Looms:
A Quick Look at the First Computer

Sadie Plant’s book, Zeros + Ones: digital women + the new technoculture (1997), reassesses women’s historical contributions to computer technology and connectivity culture. And weaving is where it all begins. The Analytical Engine, a calculating machine that used punched cards to store information in the form of a binary code, is thought to be the first computer. But why use large punched cards demanding the physical interaction of so many mechanical parts? Because the idea was developed for a different purpose altogether: to program and speed up the weaving of complexly decorated cloth.

In order to weave anything more complicated than a small repeat-pattern, a loom must lift a huge number of different combinations of threads (see fig. 2). The ancient Sassanians, Chinese, Peruvians, and others achieved marvelous effects by the use of drawlooms, but that process is slow and subject to human error. On any mechanical loom, each of the (sometimes thousands) of warp threads stretched onto the beam is threaded through a heddle. A heddle is a loop of thread or wire that can be used to lift its associated warp thread. The heddles are then grouped into different combinations on harnesses and lifted in a specific order to create a pattern. When this number of combinations reaches the hundreds or thousands… Well, the industrials wanted a faster method.

Enter the Jacquard loom. A huge stack of punched cards does the job of dictating which threads will be lifted at every single pass of the weft (transverse thread drawn through the warp). The absence or presence of a punched hole on the card either does or does not allow a hooked heddle to pass through it and be lifted. Jacquard looms also ingeniously incorporated a system of “backing,” which “meant that ‘patterns which should possess symmetry, and following regular laws of any extent, might be woven by means of comparatively few cards’.”[10] This is Plant quoting Ada Lovelace, the first computer programmer, who worked with Charles Babbage on his Analytical Engine. She also dabbled in pattern design “by programming a Jacquard loom to weave pure algebra.”[11] 

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10. Plant, Zeros + Ones, 23.
11. Ibid.

Figure 2. Weave-draft in Pointcarré Weaving Software. Each horizontal line represents which threads will be lifted for one pass of the weft. See weaving here.