Feeding the silk worm.

The art of reeling, or producing raw silk, has been carried on in China for ages, and so well did the orientals guard the secret of silk culture that the nature of the fibre was unknown in Europe for more than a thousand years after silk fabrics had been introduced there. China still takes the lead in the production of raw silk; but large quantities also are obtained from Japan, India, France and Italy. Every silk article ever made or exhibited was originally in the cocoon condition, and the fibre had to be put through a great variety of processes before it was finally ready to be woven into fabrics. The idea is quite common that the silk threads or fibres as they come from the cocoon are ready for the weaving loom without further work or preparation, but the fibres, after coming from the cocoon, must be manufactured before they can become of any value.

The little bright colored silk moth deposits from 400 to 600 eggs, and then disappears and soon dies. The eggs, on being exposed to a temperature of 65 or 70 degrees, hatch rapidly, each one producing a short brown worm, which, with a ravenous appetite, feeds upon the leaves of the mulberry tree, consuming double its weight daily. In five weeks., it attains its full growth, having increased 8,000 times in weight. It is then three inches long, and as thick as a large, lead pencil.

Cocoon—end view. (enlarged)

The worm now seeks a convenient place to begin the formation of its cocoon, which is to protect it in the changes incident to caterpillar life. Having selected a site, it ejects from two small tubes near the mouth, a liquid, gummy substance which adheres to whatever may be within reach; thus anchored, the next move of the body in the opposite direction draws out the silked fibre. The worm then turns over and over toward the center of the cocoon, and pays out the silked cable as it goes, until it has spun itself almost to death, and has built around itself a cocoon of silked thread about a quarter of a mile long.

Thus imprisoned, the insect remains, if undisturbed, for about 15 days, when the end of the cocoon is moistened, and it emerges in the form of a moth. This, however, causes the fibre of the cocoon to be badly tangled and twisted, so that it is necessary to kill the insect before it comes from the cocoon. This is done about eight days after the cocoon has been finished, by exposing it to the direct rays of the sun at a temperature of 100 to 125 degrees.

Moth

The cocoons are now ready to be reeled into raw silk. This is a very important operation, as everything depends upon the reeling, and the quality of the silk will be good or bad, according to the manner in which it is done. In silk countries the making of the cocoons is carried on as a separate business, distinct from the raising of silk worms, the cocoons being sold outright to the reeling establishments, which are known as "filatures."

If the reeling has been indifferently performed, the silk may not sell for more than $4 a pound, but if well reeled it may bring $6 to $7, and even more, depending upon the demand at the time. It is also a peculiar fact, that of two reelers each reeling half a pound of cocoons of the same quality, one will be able to obtain but 6 or 6½ ounces, and another will obtain 8 ounces.

Raw silk. First process, winding.

The filaments of the cocoon are cemented together with a gum, and to dissolve this gum requires the aid of hot water. The cocoons are placed, from 6 to 10 at a time, in a basin of hot water, and sunk by the aid of a whisk broom below the surface, where they are allowed to remain from two to three minutes. This softens the gum and loosens the fibre; then, moving the whisk broom very lightly over the cocoons, the ends of the fibres will adhere to it and are easily found.

The ends of the fibres from each cocoon in the basin are then collected together to form one thread, which is passed through a guide eye and tied to one of the barbs of the reel, and the reeling begins.

The reels are usually turned by hand, although, occasionally, electric power is used. The reel must be so far away from the basin that the gum of the fibres has a chance to dry and cool before it passes onto the reel, otherwise the fibres would become firmly cemented together. It is also important that the reel should be moved at a certain uniform rate of speed. The whole operation is tedious and necessarily expensive, as five ounces of well-reeled silk represents about ten hours' labor by an expert reeler.

Dyeing silk.

The reels are usually about 70 inches in circumference and have a traverse rod which properly distributes the thread over a surface two or three inches wide. So fine are the fibres which come from the cocoons that they are almost invisible to an inexperienced eye, and the reeler does not depend upon seeing them, but gets notice of a broken subdivision by discovering one of the cocoons at rest on the water, while the others are still in motion.

This rupture must be instantly repaired if a uniform thread of raw silk is to be obtained. A supply of cocoons is kept close at hand so that as fast as the fibre in one is exhausted, another is put in its place. The ends are joined by a dexterous movement of the reeler, who carries the end of a reserve cocoon fibre to a point just below the guide eye, where the natural gummy substance found on the silk, assisted by the movement of the reel, causes adherence to the main thread.

The twisting process.

Thus no tying of knots takes place in a single fibre of the silk while reeling, although in case of a break in all of the fibres, which is not common, a fresh start must be made, and a small knot is made, hardly perceptible in the after stages which the silk passes through. The skeins of raw silk are reeled from one to several ounces, as desired, and, on being removed from the reels, are dried and neatly packed into books or bundles weighing from 5 to 10 pounds. These books are then packed and sold in bale, containing 133 1-3 pounds each, which is the way in which the raw silk reaches this country.

Weaving silk.

On reaching the factories where the manufacture of this raw silk is carried on, the skeins are soaked in tepid soapsuds for several hours to soften the gum, after which they are placed on light "swifts" and wound off onto bobbins. This makes the raw silk soft and pliable and gives a certain lustre to it. These bobbins are placed upon pins projecting from the bobbin board of a doubling frame, and from two to ten threads, or even more, are drawn off collectively onto one bobbin, which is next placed upon a rapidly revolving spinning-frame spindle. The threads, while being drawn from the bobbins to the spindle, are given the requisite amount of twist. These spindles revolve so rapidly as to appear to be motionless, a speed of 10,000 revolutions a minute not being at all unusual.

The thread is now drawn from the spindles and doubled and twisted, and for some purposes is again doubled and twisted, so that in an ordinary three-cord sewing silk it is quite possible to have 200 or even more of the original, gossamer threads which came from the cocoon, and the lightest grades of thread contain, at least, from 75 to 80 of the fibres.

The next operation is reeling the silk into hanks of skeins for dyeing, which is one of the most important of the various processes, and requires experience as well as knowledge. After being dyed the thread is wound on spools, as desired, this operation being performed with great rapidity and accuracy by automatic machinery.

The silk cocoons vary in color from a delicate white to a dark yellow, depending to a great extent on the food of the worm and the locality in which it grew.

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© 1998, 2002 by Lynn Waterman