Last Friday I visited a silkworm farm with my sewing teacher and her interns. It's not a modern, working silkworm farm, but rather a kind of living museum that demonstrates silk production in France from the 19th and early 20th centuries. The museum is called Le Jardin du Tisserand.
It's a one-man production and he gave us a lovely tour, starting out in the magnanerie, where the worms eat, grow, eat some more and make their cocoons. You can see the latin for 'eat' in the world magnanerie. :) It takes approximately 30 days - depending on the weather and other conditions - before the silkworms decide to make their cocoons.
When they are ready to make their cocoons, they basically climb out of the box and head for high ground. They try to find the highest position possible. Then they make the silk threads to cocoon themselves and they are suspended like that, as if in mid-air, with no part of their body touching the wood. These worms are in a Japanese-style system, in wood. The worms like wood; they hate plastic.
The silk is not really differently colored, but the sticky stuff that holds the cocoon together is and it can come in white, off-white, yellow, and even green. The sticky stuff does slightly color the silk thread, so commercial silk farms use only the silkworms that produce white colored ones so as to have a neutral starting place for dyeing.
If we want the silk, we have to kill the silkworms while they are still in the cocoon, just before they are ready to emerge. Apparently they have to be killed in a very quick, specific way so as not to damage the threads. Some are allowed to live in order to reproduce.
Here's some photos of the traditional ways to process the threads, starting with the first step in the upper left-hand corner and going clock-wise.
I'm skipping lots of steps, and I'm not an expert, but here's what I remember from his explanation of the process.
First, there's some fuzzy stuff (don't remember the name!) that is removed from the cocoons, then the cocoons are heated in water and the silk threads come off quite easily. They must be unwound from the cocoon, until nearly the end. Half a dozen or more cocoons' threads are all intertwined together for strength during the unwinding process. When the cocoon becomes clear and you can see the chrysalis, you remove that particular cocoon from the batch and add another one. You don't want the thread to break off and weaken the batch.
The strands that are unwound during the removal process end up looking like real hanks of thread by the end of it. The threads then have to be further manipulated and twisted around to turn the hanks are turned into bobbins. The rate of twisting that the threads do as they are put onto the bobbins determines the quality of silk that results. For example, to get a crepe de chine, the bobbins are wound at a certain speed with a certain number of twists. I don't remember the math, sorry!
And then the bobbins are set up and the warp is created. Of course, after that you can set up the loom and weave!
The example of an industrial machine that he had on the premises dates to the early 20th century. He had it set up to weave a jacquard. The design is controlled through the little holes in those long sheets.
The photos go clockwise, with the oldest machine being on the upper left-hand corner. The exception is the photo of the date, which goes with the last (computer-like) machine.
The other looms and machines on the premises include a manual loom that takes at least two people to work it. There is also a machine that people would use to create the first part of a jacquard pattern, by placing cords in such a way to indicate where the colors ended up. The arranged ropes would then be transferred to another machine, which read the rope pattern and punched holes in the jacquard cards. It's essentially an early computer! The machine he has is from the 19th century.
There was also a passementerie loom, or a special loom that is designed specifically to make ribbons and trims. Apparently, these looms tended to be more decorated and carved than other looms.
Finally, here's a look at the mulberry trees outside the complex. The only thing that his silkworms eat are mulberry leaves, so he has to grow a steady supply himself! In fact, the latin name for the worms is Bombyx mori, with mori indicating the mulberry tree.
The cost of silk production is colossal! Frankly, after he described all the steps that are required to produce a bolt of silk cloth (and he left out a lot of them to save time), I'm surprised silk doesn't cost even more than it does. I have a new appreciation for it.
I'm sure I have given a very incomplete overview of silk production, but I wanted to share some highlights from the tour. You can probably find more complete information on Wikipedia or something; I haven't looked!
Our field trip didn't end there, however, so in my next post I might show you what we did next. Hint: it involves old wedding dresses!