SILK

the fiber derived from the cocoon of the silkworm and woven into the most beautiful of fabrics. The common silkworm is a native of the northern provinces of China or of Bengal. It is an insect of about an inch in length and its natural food is the leaf of the white mulberry. Its silk-producing organs are two large glands, containing a viscid substance, which extend along most of the body and terminate in two spinnerets in the mouth. The cocoon it spins is the envelope in which it is enclosed in the chrysalis or pupa stage. Its larvea Bp this envelope, which is composed of silk. For the culture of the worms silk producers plant mulberry trees. Silkworm eggs are carefully collected and preserved, and, after being hatched by incubator or natural heat, are placed with mulberry leaves, and begin to thrive, then moult, then eat voraciously and finally begin to spin and lay eggs. One ounce of their larvee—each a pin’s point—contains about 40,000 eggs. The silkworm is graded according to the size, color and quality of the cocoon and has many commercial varieties, After sorting, the fibrous covering of the cocoon is removed and wound, and, unlike other textile fibers, forms a continuous thread and requir es no spinning. Reeling produces the primar y material of the silk manufacturer, commercially known as raw silk. The proce thereafter does not differ from the wea; of other textiles except for the finer grades produced in Europe.: Silk originally came to Europe, then to America, from China, where the industry has flourished for 4,000 years. The world production of raw silk in the 1921-22 season was estimated at 59,437,000 pounds, of which Asia exported 48,740,000 pounds. In_ the previous season the world’s output was 44,817,006 pounds. Of this amount Europe produced 8,025,000 pounds, most of it by Italy, with 7,330,000 pounds, while France cultivated 551,000 pounds and Spain 144,000. The Levant is a producer of raw silk, with an output of 1,654,000 pounds in 1920-21. Asia, as usual, contributed the lion’s share in that season with 35,138,000 pounds of raw silk, of which Shanghai (China) produced 6,518,000 pounds and Canton (China) 4,210,000; Japan (which has ousted China of late years as the chief producer) 24,300,000 pounds; and India 110,000 pounds. ‘The figures for Asia represent raw silk exports only. Both China and Japan produce much more than they export. The silk industry in the United States, in addition to importing in 1922, 48,178,964 pounds of raw silk worth $300,445,363, spun or waste silk worth $4,435,942, and silk manufactures worth $40,337,844, is producing considerable artificial silk. ‘This material is evolved from the cellulose fiber of cotton or wood pulp which acquires all the characteristics of true silk by the application of proce es whereby it can be spun an dyed like natural silk thread. It is used for dre trimmings, hosiery, cheap ribbons, sweaters, scarfs, ties, knit dre fabrics, goods woven in combination with wool, cotton or real silk, upholsteries, electric wire insulation in the manufacture of incandescent mantles. In 1922 the American production of artificial silk was 24,406,00 0 pounds, twice as much as was manufacin 1921 and three times the output tured 1920. Artificial silk fibre and the of made from it have now an fabrics established and legitim at e place among textile products. According to census figures, 1369 establishments engaged in the Americ an industry in 1919 had a capital of sil $688,469,523 and used 25,890,728 worth pounds of raw sill.