SILK:—CATERPILLAR, COCOON, CHRYSALIS, MOTH
Organize and Tram
At the mill the raw silk goes to the "throwster" who twists the silk threads ready for the loom. These threads are of two kinds—"organize" or warp and "tram" or filling. The warp runs the long way of woven fabric or parallel with the selvage and it must be strong, elastic, and not easily parted by rubbing. To prepare the warp, two threads of raw silk are slightly twisted. Twist is always put into yarn of any kind to increase its strength. These threads are united and twisted together and this makes a strong thread capable of withstanding any reasonable strain in the loom and it will not roughen. For the woof or tram which is carried across the woven cloth on the shuttle, the thread should be as loose and fluffy as possible. Several threads are put together, subjected to only a very slight twist—just enough to hold the threads together so they will lie evenly in the finished fabric.
Boiling Off
After the yarn leaves the spinners it is again run off on reels to be taken to the dye house. First the yarn is boiled off in soapy water to remove the remaining gum. Now the silk takes on its luster. Before it was dull like cotton. The silk is now finer and harder and is known as "souple."
Loading Silk
The silk fiber has a remarkable property of absorbing certain metallic salts, still retaining much of its luster. This process is known as "loading" or "weighting," and gives increased body and weight to the silk. Silk without weighting is known as "pure dye," of which there is little made, as such goods take too much silk.
