Weaving is the result of the crossing of two kinds of threads: warp threads are longitudinal, taut, and they come from the back of the loom. They make the framework of the fabric.
The weft thread comes perpendicularly in a shuttle, which is launched from one side of the loom to the other. The way in which the threads are crossed is called a “weave”. There are three fundamental weaves: plain weave, twill and satin weave.
The weaver used a foot pedal in order to operate this loom. When he stepped on the pedal, a selection of warp threads were lifted (the warp threads are imprisoned by glass rings) thanks to the Jacquard mechanism. A space was then created between the warp threads that were lifted, and the others that didn't move. This space was used by the shuttle to pass between the warp threads. The shuttle was moved by hand, by the weaver, by pulling a cord which was in front of him. Once the weft thread had passed through the warp threads, a reed packed the weft thread against the fabric. All of these movements together were called “bistanclac” or “bistanclaque pan”:
-BIS: the weaver lifts the warp threads by putting his foot on the pedal
-TAN –CLAC: the shuttle containing the weft thread is launched between the warp threads
-PAN: the reed moves to pack the weft thread against the fabric
Each warp thread was passed through a glass ring. These needles were linked to neck cords, which were attached to hooks on the Jacquard mechanism. Each hook is itself was linked to a horizontal needle, which came in contact with a punched card:
-if the needle met the hole of the punched card, it went into the Jacquard mechanism. The hook would then move forward, and would be picked up by a bar, which was pulled up, in order to lift the selected warp threads.
-if the needle met the card, the hook didn’t move and no thread was lifted.
Each side of the card corresponded to one order, which meant the movement of the shuttle in one direction. The punched card dictated the design line by line: a whole loop of cards corresponded to a whole design. This card was placed on a circuit to be read line by line by the Jacquard mechanism. It could be endless! About 30 sides of punched card was the equivalent of one centimetre of fabric. A weaver was capable of carrying out about 100 movements per minute, so he could produce about 5 metres of fabric par day.
The Jacquard mechanism
The Jacquard mechanism takes its name from its inventor, Joseph-Marie Jacquard. In 1801, Joseph-Marie Jacquard invented this mechanism, which replaced the children's task of pulling packs of cords, which lifted the warp threads. The Jacquard mechanism works by a series of vertical metallic hooks, which lift the appropriate cords (and the appropriate warp threads) dictated by the punched card, which decides on the design.