While spinning, the worm moves its head continually from right to left, laying on the filament in a succession of lines somewhat resembling the shape of the figure eight. As the worm continues the work of making its cocoon, the filament expressed from its body in the manner described is deposited in nearly even layers all over the interior of the wall of the cocoon, which gradually becomes thicker and harder. The filament issuing from the spinnarets is immediately attached to that already in place by means of the gum which has been mentioned. When the store of silk in the body of the worm is exhausted, the cocoon is finished, and the worm, once more shedding its skin, becomes dormant and begins to undergo its change into a moth. It is at this point that its labors in the production of silk terminate and those of man begin. A certain number of the cocoons are set aside for reproduction.
In southern countries the reproduction of silkworms is a vast industry to which great attention is given, and which receives important and regular aid from the government. It is, however, quite distinct from the manufacturing industry with which at present we have to do. The cocoons to be used for reeling, i.e., all but those which are reserved for reproduction, are in the first place "stifled," that is to say, they are put into a steam or other oven and the insect is killed. The cocoons are then ready for reeling, but those not to be used at once are allowed to dry. In this process, which is carried on for about two months, they lose about two-thirds of their weight, representing the water in the fresh chrysalis. The standard and dried cocoons form the raw material of the reeling mills, or filatures, as they are called on the Continent. Each filature endeavors as far as possible to collect, stifle, and dry the cocoons in its own neighborhood; but dried cocoons, nevertheless, give rise to an important commerce, having its center at Marseilles. The appearance of the cocoon is probably well known to most of our readers. Industrially considered, the cocoon may be divided into three parts: (1) The floss, which consists of the remains of the filaments used for supporting the cocoon on the twigs of the brush among which it was built and the outside layer of the cocoon, together with such ends and parts of the thread forming the main part of the shell as have become broken in detaching and handling the cocoon; (2) the shell of the cocoon, which is formed, as has been described, of a long continuous filament, which it is the object of the reeler to unwind and to form up into threads of raw silk; and (3) the dried body of the chrysalis.
We shall first describe the usual practice of reeling, which is as follows: The cocoons are put into a basin of boiling water, on the surface of which they float. They are stirred about so as to be as uniformly acted upon as possible. The hot water softens the gum, and allows the floss to become partially detached. This process is called "cooking" the cocoons. When the cocoons are sufficiently cooked, they are subjected to a process called "beating," or brushing, the object of which is to remove the floss.
As heretofore carried on, this brushing is a most rudimentary and wasteful operation. It consists of passing a brush of heather or broom twigs over the floating cocoons in such manner that the ends of the brush come in contact with the softened cocoons, catch the floss, and drag it off. In practice it happens that the brush catches the sound filaments on the surface of the cocoon as well as the floss, and, as a consequence, the sound filament is broken, dragged off, and wasted. In treating some kinds of cocoons as much as a third of the silk is wasted in this manner, and even in the best reeling, as at present practiced, there is an excessive loss from this cause. At the present low price of cocoons this waste is not as important as it was some time ago, when cocoons were much dearer; but even at present it amounts to between fifteen and twenty millions of francs per annum in the silk districts of France and Italy alone. In France the cooking and brushing are usually done by the same women who reel, and in the same basins.
In Italy the brushing is usually done by girls, and often with the aid of mechanically rotated brushes, an apparatus which is of doubtful utility, as, in imitating the movement of hand brushing, the same waste is occasioned.
After the cocoons are brushed they are, in the ordinary process, cleaned by hand, which is another tedious and wasteful operation performed by the reeler, and concerning which we shall have more to say further on. Whatever may be the preparatory operations, they result in furnishing the reeler with a quantity of cocoons, each having its floss removed, and the end of the filament ready to be unwound. Each reeler is provided with a basin containing water, which may be heated either by a furnace or by steam, and a reel, upon which the silk is wound when put in motion by hand or by power. In civilized countries heating by steam and the use of motive power is nearly universal. The reeler is ordinarily seated before the reel and the basin. The reeler begins operations by assembling the cocoons in the basin, and attaching all the ends to a peg at its side. She then introduces the ends of the filaments from several cocoons into small dies of agate or porcelain, which are held over the basin by a support.
The ends so brought in contact stick together, owing to the adhesive substance they naturally contain, and form a thread. To wring out the water which is brought up with the ends, and further consolidate the thread, it is so arranged as to twist round either itself or another similar thread during its passage from the basin to the reel. This process is called "croisure," and is facilitated by guides or small pulleys. Having made the croisure, which consists of about two hundred turns, the operator attaches the end of a thread to the reel, previously passing it through a guide fixed in a bar, which moves backward and forward, so as to distribute the thread on the reel, forming a hank about three inches wide.