Our friend, the weaver

Sign for the Foundazione Lisio

Nancy and Dan visited us in Florence for a few days and led us to an interesting experience on a topic we knew very little about. Nancy is a weaver with looms in her home near our home in Syracuse. Her machines are made of wood and are impressively sturdy and large. While she was in Florence, Nancy’s interest was to visit the Foundation Lisio on the outskirts of the city where the ancient art of hand weaving has been kept alive using traditional Jacquard looms.

A Jacquard loom

The organization is properly called the Foundazione Arte della Seta or the Foundation for the Art of Silk Making. The organization is headquartered in the hills south of the Florence where, on the morning of our visit, the flowering trees were in blossom and the sun was warm. In their building they manufacture brocades and velvets made from silk, all woven by hand on commission. The Foundation also holds classes in the facility for weavers from around the world and maintains the Jacquard looms as fascinating objects of the history of technology. The tour included the four of us and was led by Eva Basile, the Lisio School Director.

Strings above control
shuttle cock threads

Florence has a long association with textiles. Textiles made from wool were a thriving industry in Florence and Tuscany in the early years of the second millennium. Eventually Florence became a leader in banking, originally in support the trade in fabrics. With the great success of banking, Florence became a power in central Italy and eventually home to the Renaissance, the stupendous flowering of thought and art between 1200 and 1600 that was made possible, in part, by the wealth of the city.

Silk came to Florence from the Orient early in the Renaissance. Silk worms and the techniques for harvesting silk and turning the threads into rich fabrics became as important an industry as woolen fabrics.

The Jacquard looms used at Foundation Lisio were invented in France in the early 1800s. These looms were very complex mechanically and multiplied the productivity of a worker many, many times and, consequently, enlarged the market for fabrics made from silk.

How plush velvet is made

A Jacquard loom has two sources of threads for the ground, the basic fabric. A shuttle cock flies through these threads and then the positions of the two sets of ground threads are switched, holding the shuttle cock thread in place. At the heart of a Jacquard loom is a mechanism above that controls which threads in the ground fabric are lifted so that the shuttle cock thread can come to the surface and be seen.

Punch cards control the design

Yes, yes, this sounds pretty complicated but it’s probably more complicated than one might imagine. At the Foundation silk fabrics are woven at densities of 250 threads per inch. That is incredibly dense considering the image on a high resolution computer display is 72 dots per inch. An ordinary television is 30 dots per inch.

In a Jacquard loom hundreds and hundreds of individual strings hang down, held in place by tiny weights. The strings lift up (or fail to lift up) the threads in the ground fabric. When an individual string lifts up, color from the shuttle cock thread peeks out from the silk background color.

Shuttle cocks with metallic threads

The very high “resolution” of the silk produced is not the only connection with modern computers. The individual strings that lift (or fail to lift) the individual threads are controlled by punch cards. Holes in the punch cards allow a string to be pulled up, the lack of a hole prevents the string from being lifted up. There isn’t much difference between Jacquard punch cards and the old IBM punch cards that some of us may have used (if one is over a certain age.) Fabric designers “programmed” their Jacquard looms to produce particular designs with a particular set of cards. A new set of cards would produce another design. The Jacquard was a special purpose computer elegantly designed for one purpose, that is, to weave beautiful fabrics.

A sample of velvet made on
a Jacquard loom

The tour leader showed us a tool in two halves, made of cast iron and quite heavy, that was used to make the punched cards. The metal had holes in every position where a hole might be punched in a card and a card fit nearly inside between the two halves. The user took a cylinder of metal and punched holes in a card with a little hammer to make the cards and to program the loom. This process of “programming” must have taken forever. Dan wondered aloud how these “programs” would be “debugged”. You’d have to be pretty far into weaving to see mistakes erupt and we understand that such mistakes could not be fixed easily.

Spools of satin thread

Eva Basile said that she had learned this primitive method for punching cards when she was 15 years old and that it was reasonable for a 15 year old to be tied to such painstaking process and such a primitive tools. It helped to focus the mind. There were machines in the workshop for punching holes in the cards much more quickly.

The Jacquard loom has relatives such as the player piano and the music box, other single purpose computers. The invention of the modern electronic computer dates to World War II when scientists in Britain built single purpose computers to break the famous German Enigma codes.

The looms are noisy. The video clip gives a sense for what one loom sounds like. A factory full of these machines all making fabrics would very noisy.

The tour was fascinating especially for someone who is also interested in computers and the history of computers. Because the loom is controlled by a "program" stored on punch cards, a Jacquard loom is in the center of the computer exhibits at the Ontario Science Center near Toronto as an example of an early programmable device, that is, an early computer.

For the report of a group of weavers who spent some weeks studying at the Foundation Lisio, see New World Technology Meets Old World Weaving,