Page:The American Cyclopædia (1879) Volume XV.djvu/49

 SILK > 290 Ibs. in 1770. The business was entirely broken up by the revolutionary war. In South Carolina silk growing was practised before the revolution by the Swiss settlers at Perrysburg, and also by the French, who wrought it up with wool into fabrics. In 1765, 630 Ibs. of cocoons were raised upon a plantation in St. Thomas parish ; but though some progress con- tinued to be made in the business, it was at ast brought to an end by the same causes that roke it up in Georgia. In Connecticut the culture of silk was also undertaken at an early period, and was encouraged by the home gov- ernment as in the other colonies. Dr. Aspin- wall succeeded in establishing the business in Mansfield, Conn., where it is still carried on, id before the revolutionary war it was already a very promising condition. In 1789 about iOO Ibs. of raw silk, worth $5 a pound, were ade at Mansfield ; it was mostly manufactured into stockings, handkerchiefs, ribbons, buttons, id sewing silk worth $1 an ounce. In 1790 about 50 families in New Haven were engaged the business, and in Norfolk about 30 fam- ilies raised and spun 1,200 " run of silk." In 1839 the product of Mansfield and its vicin- ity is reported to have been about five tons of raw silk. In Massachusetts attention was also directed to the silk culture in the latter part of the last century. The town of Ipswich was loted in the manufacture of silk and thread lace. A filature was opened in 1770 at Phila- lelphia, and 1771 from June to the middle of August it received 2,300 Ibs. of cocoons. In )me of the interior towns of Pennsylvania, Washington in the S. W. part, silk is still )roduced to a moderate extent, and not only mverted into sewing silk, but also woven. In )hio, the E. parts of Kentucky and Tennessee, .d N. Georgia, the production has proved well ted to the soil and climate, and many have iticipated for it a great success in this portion >f the country. There seem in fact to be no tural obstacles to the prosecution of the busi- less over all the middle and southern portion " the United States. Several species of mul- 3rry, quite as well adapted for feeding the rorms in the early stages of their growth as 'ie white mulberry, grow wild from Pennsyl- vania southward, and are* easily cultivated in )ther districts. The foreign species of the tree lave also been introduced, and are now almost well known as the native sorts. The total >roduct of silk raised in the United States in [840 was reported at 61,552 Ibs., worth about 50,000. In 1844, according to the report of the commissioners of the census, it was 396,790 Ibs., worth $1,400,000 ; but in 1850 it was only 14,763 Ibs. The United States census of 1870 gives no statistics of native silk culture ; neither is there any mention of American silk in the "Report of the Silk Association of America" for 1875. The growth and manufacture of silk have been successfully attempted in Cali- fornia. Just before the breaking out of the Franco-German war, French cooperation had been secured for the establishment of a silk colony in San Bernardino co. ; but the project failed, owing to the disastrous termination of that conflict. There was in San Jose in 1875 one cocoonery with about 1,000,000 silkworms, and a silk manufacturing company has been organized in San Francisco. In the same year Sonoma co. had an. association for the pro- motion of silkworm culture. SILK MANTJFAC- TUEE. The cocoons consist of the sheath of loose filaments attached to the twigs that sup- port the whole, and beneath this the external coat of soft flossy silk, within which is the compact oval ball, or cocoon proper. The thread, as laid by the worm in successive coats in his constantly diminishing tenement, is not wound regularly around the inside of the hollow ball, but is passed back and forth in one place after another in such manner that many yards may *be wound off without turning over the ball. It is produced through two orifices in the nose of the worm, and the two fibres on issuing forth are secured together by the glutinous matter which accom- panies them and forms nearly one quarter of their weight. The average size of each one of the primary fibres is about ^Vs of an inch. Raw silk consists of any number of the double filaments slightly twisted and agglutinated to- gether to form one thread, called single. This is commonly of a golden yellow color, of spe- cific gravity 1*3, and is the strongest of all fibres used for weaving, threads made of it being three times stronger than those of the same size made of flax, and twice as strong as those of hemp. Some of the best cocoons are kept for breeding ; the remainder are clas- sified, each sort being worked by itself. Be- fore the chrysalis matures and the moth can begin to eat his way out, the cocoons are ex- posed to a moderate degree of heat, either in an oven, or in a steam bath, or in water heated to about 200 F. The floss covering being opened at one end, the cocoon is slipped out, and is then ready to be unwound. The co- coons are placed about five together in each one of four compartments in a sort of trough or basin holding hot water, which is kept at the necessary temperature by a steam pipe. The gummy matters are softened by the water, and the fibre is thus released. The ends are caught up by a little sort of broom with which the cocoons are stirred, and those from each com- partment being brought together are passed through an eyelet, which strips off a portion of the gum, and still more is rubbed off by causing the threads formed by each bundle of fibres to cross and rub against each other, as they are conducted diagonally through a suc- cession of eyelets toward the reel, just pre- vious to reaching which all are united in one thread. The reel is set at some distance from the trough, to allow the gum to harden, and prevent the threads from sticking together; and it has a slight Literal motion, so that the threads are laid in spirals, and do not come in