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Virginia. Its food is the elm, the willow, and other trees. The cocoon is of loose texture and coarse silk.
THE MANUFACTURE OF SILK.
To transfer cocoons into the raw silk of commerce a basin and reel only are used; the former containing warm water to soften the gum of the envelope, so that the silken layers of the cocoon may be set free. In reeling, a certain number of threads of the cocoons, in proportion to the standard of raw silk intended to be produced, are united by pressure and twisting. This union of raw threads is known as grége or raw silk. Great care must be taken to prevent the threads, issuing wet and gummy from the basin, from adhering together; a sufficient distance between the basin and the reel, to permit a partial drying must be allowed, and a guide-thread be so arranged as to secure a zigzag movement, which prevents the threads from crossing one another. The following suggestions in regard to this branch of the work are given : The degree of previous preparation should vary with the durability of the silky couches, having regard to the age, breed, and origin of the cocoons. If prepared too much, the result would be that more silky matter would be yielded by the first layers than there should be. This superfluous matter would be only waste, and would possess a value much inferior to that of fine silk. If the cocoons are, on the contrary, insufficiently prepared, they .present a resistance to the winding off, which causes the breaking of the thread, and leads to a new source of waste. The workmen ought . to possess great skill in joining a new thread to thread in work. He should be competent to select the most opportune moment to assure the regularity of the product, so that the trace of these successive connections may be imperceptible to the eye, and thus avoid knots, coarseness, curls, or dots. Nor will rare skill in these particulars produce the effect desired unless the wheel revolves with a fixed and steady velocity of at least five hundred meters per minute. Without this, the thread, instead of being smooth and brilliant, would be rough and dull. Atoo slow movement would not dress the thread sufficiently, clasped as it is very tightly by its peculiar position, and fixed under the form of a figure 8 in the layers of the cocoon. A movement too slow causes those undulations which give the dull appearance; while the development of the thread in the straight line by the more rapid movement permits the reflection of the light in those perfect and determined conditions which give brilliancy to the finest silk.
At the Paris Exposition almost every European nation was represented by different mechanisms employed in the manufacture of silk. Vír. Cowdin is careful to name the uses, and particularly describe the best of these.
A very ingenious apparatus, invented by G. Honpeger, of Switzerland, for the sorting of silk threads was exhibited. This machine receives on the one part a series of silk skeins, to each of which correspond a num. ber of bobbins or reels, equal to that of the varied bulk, supposed to be contained in the skein.Each bobbin will receive the portion of the thread of the titre for which it shall have been designated. For this purpose, the thread which is rendered from the skein to the bobbins is guided automatically by a mechanism for gauging, extremely sensitive, and so arranged that the grége or raw silk in passing acts upon a lever which directs the silk upon the proper bobbin. The variation in the bulk of the product is the point of departure in the variation of the gnide lever, which directs the thread to the reel proper to receive it.
By the employment of this machine, it is thought, the cheap silk of the East may find more extensive applications, and contribute to a new development in silk industry.
Professor Alcan exhibited an apparatus for testing the tenacity and elasticity of filaments and threads, and determining the degree of ten. sion most suitable to be employed on any given thread. The instrument is described as one of rare precision, very simple, and not expensive.
The throwing of silk is intended to give a peculiar appearance to the threads, which partly determines what is called the grain of the stuff. It requires accurate knowledge and rare skill. The machines exhibited at the Exposition, used in this branch of silk industry, were those employed in the best factories, especially those of Switzerland. These consisted of, 1st, a series of tavelles to wind, clean, and equalize the threads during their automatic winding off ; 2d, an apparatus to unite and double the threads, with a mechanism for instantly stopping the machine whenever a thread breaks; 3d, a machine to give the first twist to the double threads in the direction determined for the production of the tram or woof; 4th, a second machine to retwist together two threads already twisted separately, thus producing organzine. The object of these machines, which are simple in their construction, is to obtain constantly an evenly twisted product.
The attempt to unite in a single operation the winding off of cocoons and the throwing of silk has not been successful. Commissioner Cowdin refers to the mechanism exhibited by the Italians and French, and claimed as solutions of the problem, as possessing minor interest, and affording little encouragement. It is his opinion that the desired process, which is enticing in appearance as a great saving of time, labor, and money, is deceptive, demanding an expense much greater than that of the separate operations, and that it would yield inferior products of inconsiderable value. Simultaneous twisting and throwing, however, may be employed with a certain success when the cocoons are of an inferior quality and difficult to wind off, such as double cocoons, so that the operator in twisting them directly can, at the best, obtain silk of a very inferior grade, fit only for working common cordonnet, (braid, bind. ing, twist, lace, &c.)
The "wasto" occasioned by the various manipulations of silk until it becomes stuff, has long been utilized, and also, more recently, since silk became very high, the chiffons, or rags of that material. In the show-cases of the Exposition, France and Switzerland displayed threads made from waste, which rivaled in beauty of appearance the most lustrous silks, and at one-half the price. The result is obtained by attention to details in the manufacture. When the threads from waste have been produced with the greatest care, well purified, well combed, perfectly prepared and spun, a thin layer of warm gelatine or isinglass is applied to them when stretched and in motion. Sweepings of threads, formerly thrown away because the workmen could not unravel them, are now made valuable by the use of ingenious and effective machines. These machines take the rag or piece of silk at their entrance, and re. store it at the exit in the form of filaments, classed in lengths and fine. ness proper to be submitted to the machines for decomposing the chiffon or rag. These machines were not exhibited at the Exposition by the inventors, from fear of imitation by countries where inventions are not protected by patents.
Referring to the dyeing of silk, Mr. Cowdin says:
“ The invention of those colors derived from coal has principally contributed to or caused a revolution in the art of dyeing. The new materials have permitted dyers to obtain colors of unprecedented splenaor, combining shades of marvellous variety with extreme delicacy. Looking through the Exhibition we might almost say, in the presence of results obtained in this direction, there is now nothing impossible. Still, close by the side of products so admirable in respect to dyeing, we saw, on the contrary, much still left to be accomplished. We refer to the attempts made for some time to gild and silver threads of silk. Some specimens of silk of this kind exhibited denote processes still in a crude state, which do not yet supply any product capable of being used to advantage."
The plain silks of France, Switzerland, and Northern Germany attracted great attention on account of their thorough finish and general excellence. They were exhibited with the special notice that the wearing was done by motive power. The improvements in the looms of these nations secures cleanness, purity, and brilliancy. French apparatus has been introduced to polish plain stuffs automatically. This machine possesses all the advantages of hand-polishing, acting with only a little polish and in parts. Automatic looms for the manufacture of velvet stuffs are of two kinds, one for working two pieces at a time, and the other a piece singly. By the former, various articles in silk, and the most beautiful plushes for hats are made. For the manufacture of striped and plaid silks the Scotch looms excel all others. In the silks for toilette, especially in façonnés, or figured goods, a fineness and neatness that seemed almost impossible has been attained by French industry alone. Ingenuity has been tasked to simplify the Jacquard loom and render it capable of producing still more extensive results.
At the Exposition, products of the silk-ribbon loom were exhibited by the manufacturers of Saint Etienne, Basle, Prussia, Alsace, and other sections. Saint Etienne contains 90,000 inhabitants, and gives employment to 23,622 persons, of which the greater part are women and girls. It has 15,000 looms. The value of its productions in 1866 was $12,000,000, five-sixths of which were sold to the United States, England, and to the city of Paris. Basle, with a population of 65,000, has 6,000'looms. At Alsace steam was first employed in the manufacture of ribbons. Some of the ribbon factories run 200 looms by a steam-engine of thirty horsepower, and employ 600 persons.
In the opinion of the commissioner, four of the seven industrial branches employed in the transformations of silk can from this period develop themselves in America without any difficulty, and soon take the high position already attained by cotton industry, namely:
1. The throwing of silk, consisting in the employment of apparatus more simple and also less difficult to direct than the greater part of the machines in the factories of the United States. It is as easy for the United States as for England to obtain immediately a supply of raw silk in China, Japan, and even in the Levant and India. It is not improbable that New York may become as important a depot for Asiatic silks as London now is. This may be accomplished through the medium of the Pacific railroad. The raw material having thus reached New York, will be distributed not only among our own manufacturers, but portions, doubtless, will be exported to foreign countries. Let England be taken as an example in this industry. In less than fifty years the silk manufacture of Great Britain, which does not upon her own soil produce a single pound of raw material, has arrived at such a degree of development as to give employment to a large amount of capital and to about 110,000 looms, and direct occupation to some 200,000 persons, not includ. ing those engaged in the ribbon and silk hosiery manufacture.
2. The dyeing of silk, already an established branch of American indus. try, needs only the encouragement to be derived from the establishment of co-operative branches to compete successfully with European skill.
3. As to the regeneration and spinning of silky waste of all kinds, the United States find themselves in as good a position as most other coun. tries to undertake a work of this sort, inasmuch as they possess equal facilities for procuring the waste and raw silk. This branch of industry in France gives employment to more than 30,000 workmen, and the annual production exceeds $20,000,000.
4. With regard to the automatic weaving of plain stuffs, the United States already compete successfully with the more experienced nations of Europe. Looms exhibited by American constructors at the Paris Exposition were highly appreciated for their ingenious contrivances and remarkablą improvements.
Three specialties remain, therefore, to excel in which time and effort only are necessary, viz: The rearing of silk-worms, the reeling of the cocoons into raw silk, and the weaving of figured goods. As has already been shown in this article, the culture of the mulberry in many portions of this country has proved very successful-in some eminently so. The cocoons of California are equal to any in the world. Native silk once supplied in sufficient quantities to enlist the inventive genius and mechanical aptitude of our people, will speedily solye the problems presented in the remaining specialties just cited. The country which produces the most skillful and careful spinners of wool and cotton manafactures will not despair of arriving eventually at the successful production of the many kinds of silk goods within its province.
MANUFACTURING IN THE UNITED STATES.
The present processes in American silk manufacture are thus described in the New York Tribune, with a reference to the localities and personnel of the business at the present time:
“ The first process is to sort the raw silk into sizes, great care being required in every stage that the threads be equal in size, as inequality would produce a manufacture of uneven and unmanageable twist. It is then soaked in soapy water to dissolve the gum and render the thread pliable and elastic. The skeins are slipped upon octagonal, wicker
swift' reels, a dozen or more of which revolve on an axis fastened on the legs of each table. A thread from each reel-skein passes upward over a smooth metal or glass rod, fixed on the lateral edge of the table to its revolving bobbin, upon which it is wound. After this process the thread is guided between the contiguous edge of two sharp steel knives, resem. bling scissors, which cleans it of gummy lumps and clinging waste, to another bobbin. This process occasions considerable waste. The tiner and more regular threads are now taken for making organzines, which are the warps of woven goods. Coarser threads are taken for trams or woofs. The most inferior are used for the manufacture of sewing-siiks. Loose and broken ends are corded like cotton and spun into tloss for embroidery. The twisting or throwing' process is done by passing the thread of raw silk froin an upright bottom through the eye of a craned wire flyer, which rapidly spins with the top of the bobbin revolr. ing above. This thread is called a "single,' and for organzines receives from twelve to nineteen twists to the inch. Organzines or trams are made by twisting together two of these twisted threads in an opposite direction to the former single twist, at the rate of from ten to seventeen turns to the inch; the two threads having previously been wound parallel upon one bobbin. Organzines receive tight twisting, to induce strength and elasticity. A swing of two twists to the inch sometimes saves five cents to the pound in the cost of labor, but may occasion greater loss in weaving. Two or three threads of raw silk twisted loosely two or four times to the inch is tram, shute, or woof. In weaving, the woof has little or no strain upon it, and it fills up the warp better by being soft and loose. The twist in silk threads is set by dampening and drying. Skein sewing-silk is made of three to ten threads twisted together, and two of these latter doubled. Sewing-machine silk is trebly twisted. Button-hole twist is the same, with a tighter twist. Twists in the single threads of sewing-silks are ten to fifteen to the inch; and the doubled, eight to twelve. The organzines are reeled into skeins of one or two thousand yards each, care being taken to make them of the exact length, as that compared with their weight determines the quality of the goods to be woven. The American sew. ing-silk machine is a great improvement over the old-fashioned one. By the aid of a few girls, the former at once doubles and twists the silk, and reels it into skeins of equal length; and it turns out one hundred and twenty-five pounds a week. The cost of throwing raw silk into organzines is four to five dollars per pound, a great proportion of that going to labor. Trams cost less. After weighing, the threads go to the dyer, who is charged with the weight; also with the number of skeins. As the manufacturer knows how much of each color should be returned, little fraud or error can happen. Up to the time the silk goes to the dyer, there is a loss of three to nine per cent. from cleaning, breaking, &c. It loses eighteen to twenty-five per cent. of the weight in dyeing by the boiling off of the worm gum, which is made up greatly by sur. charging with sugar or dye. In the dye-house the silk skeins are tied to prevent tangling, and boiled for four or five hours in coarse linen bags, by which the hempy colors attain a luster. Yellowish colors are coun: teracted' to pure white by the use of a little blue dye. This white dyeing costs sixty cents a pound-less than any other color. Of white colors the manufacturer receives back from the dyer twelve ounces for every pound. The aniline or bright colors cost $1 50 to $3 50 a pound to dye. The bright greens are the most expensive. They also return twelve ounces to the pound. High colors are cheapened in the weight by the addition of three ounces of sugar to twelve of silk. Drabs and slate are dyed with sumac at a cost of a dollar a pound, and return fourteen ounces. Blacks are dyed with nitrate of iron and cutch, and also logwood, a bluish shade, especially for velvets, being desirable. Blue-blacks return fourteen ounces; plain blacks the full complement, losses being compensated by surcharging. Surcharging can be carried to the extent of trebling the weight of the silk. After dyeing, the skeins are dried on bars in a close-steamed room, and then lustered by passing over hot cylinders. Sewing-silk is softened by wringing, and tied into skeins for sale. Trams and organzines are then rowound upon bobbins, and again rewound to give a proper tension to the thread before weaving.
PRESENT CONDITION AND PROSPECTS.
"Such is the extent to which the American trade las usually been carried, though pongees and foulards were woven in Connecticut, and ribbons in Baltimore, twenty years ago. During the last ten years the manufacture of ribbons has increased rapidly. The Cheney Brothers, of Hartford, are making great quantities of parasol coverings; the Dole Company,at Paterson, N. J., are making tailors' trimmings, scarfs, and braids,