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papers being unrolled, they are seen to be covered its own skin head foremost ; lucubrating its body with worms.
In the colder latitudes the Chinese to assist the extrication, fixing the skin to a mulhave recourse to the heat of stoves to promote the berry-leaf by filaments of silk spun srom its mouth, hatching of the eggs.
and making its escape by slow degrees. The The apartments in which the worms are kept operation appears to be a painful one, for the little are in dry situations, in a pure atmosphere, and animals are observed to rest several times during apart from all noise, which is thought to be its progress, and to be much exhausted on its annoying to the worms, especially when they are completion. young. The rooms are made very close, but with When nature has given it a more easy-fitting adequate means of ventilation. Each chamber is coat, the busy silk.worm proceeds to eat with provided with nine or ten rows of frames placed great voracity, and increases to the length of half one above the other; on these frames rush hurdles an inch in five days. The second coat has become are placed, upon which the worms are fed and by this time too small for the wearer, and is abankept. A uniform degree of heat constantly doned in the same manner as before. In its third preserved, either by means of stoves placed in the stage the worm keeps on eating as before, increases corners of the apartments, or by chafing dishes, in five days more to three-quarters of an inch in which from time to time are carried up and down length, and then requires a third molting or the room. Flame and smoke are carefully avoided. enlargement of the skin. Another period of five The most sedulous attention is paid to the wants days elapses, a further enlargement to an inch and of the worms, which are fed during the night as a half in length takes place, a fourth sickness well as the day. On the day of their being hatched supervenes, and for the fourth time the worm, they are furnished with forty meals; thirty are finding its skin too tight for its bulky body, creeps given on the second day, and fewer on and after out of it altogether, and enjoys a freer existence. the third day. The Chinese have such a strong This is now the fifth stage of its existence as a opinion that the silk produced depends on the worm, and it proceeds to eat so voraciously (mulquantity of food eaten, that when the appetite of berry-leaves being still its favorite food), that in the worm Aags, from temperature or other causes, ten days it attains a length of two inches and a they contrive means to stimulate it artificially. half or three inches.
The quicker the worm arrives at maturity, the The time now approaches when the silk-worm, greater is the quantity of silk produced; and hence having received so much food from its attendants, every care is taken to hasten its development. yields more than an equivalent in the form of The changes which the little animal undergoes silk. The worm ceases to eat, appears restless during this time are most remarkable. In the and uneasy, seeks about for some place to spin first place, the egg from which it is produced is its silk, and forms a sort of resting-place in some about the size of a grain of mustard-seed, and the nook or corner. The body of the worm at this worm itself, when first hatched, is a little slender time contains a secretion which afterward constithread about a quarter of an inch long. During tutes silk; it is a fine yellow transparent gum, its growth it will wander about in search of food; contained in two slender vessels in the stomach. but if mulberry-leaves be supplied to it in plenty, The worm spins or expels this gum from two it will remain stationary, occupied during the small orifices in the head, uniting the two into early days of its existence almost wholly in eating. one thread by a peculiar action of the mouth, When it is about eight days old, its head enlarges and laying the silken thread thus formed in such and the worm becomes unwell; it remains three a way as to build a hollow ball, nest, or “cocoon." days without food, and in a lethargic state. In The little spinner remains within his prison-house, fact, its growth has been so enormous, that its skin building up around him a silken wall, and spreadis too tight to enclose its bulky body; and this ing and arranging the thread with his front feet sickness seems to indicate the period when the in waving lines around him. In this way each old skin or envelope is abandoned, and gives way worm spins about four hundred yards of delicate to a new one, more consonant with the increased silken filament, which is arranged into a hollow size of the animal. The process is a most extraor- egg-shaped mass, measuring about an inch and a dinary one, for the insect literally creeps out of half long by an inch in diameter.
When the cocoon is formed, the insect smears time. The cocoons are exposed to the heat either the inner surface with a peculiar kind of gum, of the mid-day sun or of an oven until the insect which is also used to make the silken thread within is stifled. This being done, the external cohere in making the cocoon. The animal has soft envelope is removed from the cocoon, the become by this time wasted and wrinkled, and former constituting floss-silk, afterward brought then throws off its caterpillar state, assuming the to the state of yarn by spinning, and the latter form of a chrysalis. It remains as a chrysalis being afterward manufactured by silk-throwing. during a period of from fifteen to thirty days, and The three or four hundred yards of filament seems during this time to be preparing itself for forming each cocoon are agglutinated together by its final stage of existence as a winged moth. a sort of gum applied to them by the insect; and When this stage is attained, the moth softens the it is necessary to soften this gum before the filagummy interior of its house, and gradually works ment can be unwound from the egg-shaped ball. for itself a hole through the cocoon, emerging at To effect this, a number of cocoons are thrown length into open day as an active but short-lived into a vessel of hot water, and there allowed to moth.
remain till the gum is softened. The reeler, or It will thus be seen that the silk.worm goes person employed, then takes a whisk or kind of through many remarkable changes. It is first brush made of fine twigs, and presses its end confined within its egg, then it emerges as a gently on the cocoons. One filament from each worm, then casts its skin four different times, to cocoon adheres to the whisk, and is made to accommodate its increasing bulk; envelopes itself commence the process of unwinding. In this in a silken nest, then changes to a chrysalis, the manner the person reeling gets the thread of intervening stage between the worm and the several cocoons between the fingers, ten or twenty moth; and lastly assumes the usual appearance of in number, and attaches them all to the reeling a winged insect. Their increase in size, and the machine. They are grouped into parcels conquantity of food devoured by them, are quite taining three or four threads each, then these are remarkable.
again combined, then two of these larger parcels, Fifty thousand silk-worms, when just hatched, and so on until all are combined to form one weigh only an ounce; there are only four thou- thread very much thicker than the individual sand to an ounce at the period of casting the first filament, but still an exceedingly fine thread. skin; only six hundred at the time of the second | This thread is wound on a reel or hollow frame, molting; only a hundred and fifty at the time of the reeler replacing the spent cocoons by new the third; only thirty-five at the time of the ones, and having the water of such a temperature fourth; and when just ready to spin, six of them as tu soften the gum just as fast as the silk is weigh an ounce, so that in the period of five or required to be wound. When the silk, after being six weeks the silk-worm increases in weight nine wound on the reel, is removed from it, it forms a thousand-fold! Their voracity may be thus illus- skein or hank, which is fastened up in a convenient trated : the worms proceeding from one ounce of form to send to market. eggs will consume six pounds of mulberry-leaves The number of insects required to produce any before their first molting; eighteen pounds be considerable weight of silk almost exceeds belief. tween the first and second ; sixty pounds between Supposing each cocoon to yield on an average the second and third ; one hundred and eighty three hundred yards of silk, it has been estimated pounds between the third and fourth, and more that the original silk filament, as produced by the than a thousand pounds between the fourth molt-insect, would require nearly five hundred miles of ing and the period of spinning their silk, thus length to weigh one pound! Two hundred and consuming, in six weeks, twenty thousand times fifty average-sized cocoons weigh about a pound, their own weight of food !
and eleven or twelve pounds of cocoons yield one If the moth be left to itself, it will live within pound of reeled silk, the other eleven-twelfths its cocoon till a proper time, and then make for being made up of the weight of the chrysalis, itself a means of escape ; but when man chooses foss-silk, waste, dirt, etc. to appropriate the silk to his own use, he puts the An excellent authority upon this subject relittle hard-working prisoner to death before its marks : “ The quantity of silk material used in
No. of DAYS
700 to 760
750 to 800
750 to 800
England alone amounts in each year to more than (fourth best lb), $50. The amount thus to be four million of pounds weight, for the production distributed is the contribution of Messrs. Strawof which myriads upon myriads of silk-worms are bridge & Clothier, of Philadelphia, a firm comrequired. Fourteen thousand millions of arimated creatures annually live and die to supply
CHART SHOWING THE this little corner of the world with an article of
DEVELOPMENT luxury! If astonishment be excited at this fact,
OF THE SILK-WORM. let us extend our view into China, and survey the dense population of its widely-spread region, whose inhabitants, from the emperor on his throne
HATCHING. to the peasant in the lowly hut, are indebted for their clothing to the labors of the silk-worm. The imagination, fatigued with the flight, is lost and bewildered in contemplating the countless numbers which every successive year spin their slender threads for the service of man."
As we have already observed, few persons rear the silk-worm and manufacture the silk; the breeder sells the cocoons, and the manufacturer superintends the future processes. The industry in the United States is, therefore, at present sim
Ist Day ply confined to the rearing of silk-worms and the culture of the cocoon. As the market is near and the demand great, this industry alone offers the most tempting inducements for persons to engage therein. It is especially adapted to women,
who may desire to employ their leisure monients, with a view of adding a suitable competence to their usual income, and is, moreover, a pleasant and agreeable occupation, requiring little more labor than mere attention to the little workers.
1st Day The industry, we are pleased to state, is rapidly increasing, and much interest is being paid to its full and proper development. The liberality and enterprise of many of our leading silk merchants and manufacturers are enlisted in the industry, through the proper dissemination of correct modes of treatment in the rearing of the silk-worm, and to stimulate healthy competition very handsome 1st Day Creampie cash premiums are being offered for the display of the best cocoons. The “Women's Silk Culture Association of the United States,” the most prominent factor thus far in the promotion of this industry, has just announced the holding of a fair in the city of Philadelphia, during the third week in October next, for the best displays of silk cocoons. The cash premiums offered are four in number, and for the best four grades of silk cocoons, to wit: First premium (best th), $200. Second premium (second best th), $150. Third premium (third best 1b)), $100. Fourth premium
10 4th "
21 6th "
posed of liberal and enterprising gentlemen, and worms have come through the net or paper, who have at all times manifested a very deep remove, and place a second paper with leaves for interest in the subject of silk-rearing in this coun- the remainder; in the same way the space may try.
be trebled by removing one-third at a time. The The indications are that the silk-rearers of the leaves should be spread evenly, so that the worms United States will be well represented at this may get the same amount of food and keep exhibition, and the displays of cocoons be both together in their growth, as it is important to have creditable and excellent. The Association is them molt together. actively engaged in the work of disseminating The leaves must be red fresh and dry, never wet information on the subject, and has had prepared or wilted; leaves wet with dew are espec ally under its auspices a chart containing general in- injurious. Gather the leaves in the evening, for structions for the benefit of silk-rearers throughout the next morning's meal, and when rain threatens, the United States. For the benefit of the readers gather a day ahead and keep in an airy, cool of the MONTHLY we quote them in brief:
place, stirring occasionally to prevent heating and
fermentation, which will ruin them. If only wet DIRECTIONS FOR THE MANAGEMENT OF A COCOON- leaves can be had, dry them by shaking up before
a fire, or in a breezy place. When food is scarce, Hatching.–The eggs are usually kept at the lower the temperature of the room, and the worms temperature of ice until hatching time. When will eat less. removed from the ice, put in a cool place two or For young worms, gather only the small leaves. three days, so that they may be brought gradually After the second age, small twigs or branches to the temperature of the air. As soon as the may be cut with the leaves.
For this purpose use mulberry leaves have begun to open, spread the a knife, or better, clip with pruning-shears. eggs on clean white paper; an ounce will require Gather in a basket, or better, in a bag tied about a square foot of surface. The temperature should the waist. be about 70°, and may be gradually increased 1° The or 2° a day, to 75° or 80°. They will hatch rapidly. The worms are said to consume their usually in five days, but the higher the tempera- own weight of leaves daily. The worms from an ture the sooner the hatching. The worms will ounce of eggs will require about one pound of commonly hatch out in the morning, for three or leaves the first day, two pounds the second, three four successive days. When the hatching begins, or four the third ; after that the quantity diminspread over them musquito-netting or perforated ishes as the time of molting approaches. paper, and when the morning's hatch has crawled After the second or third age, the net (or paper) through, remove to the frame or platform, mark- and frame may be discarded, and the leafy twigs ing, and keeping each day's hatch separate. or branches with the worms may be placed on Better use the net for the first age, and the paper the platforms directly. The successive feedings afterward.
of twigs are spread evenly on the old ones until Feeding.–The worms should be fed as soon as the mass is piled up four or five inches to the next hatched and removed, by sprinkling young and tier of pins or nails, then lay a new set of five tender leaves over the net or paper; repeat the bars or sticks, with the food, on these, and when feeding every two or three hours during the first the worms have ascended, drop out the lower tier age, and afterward every three or four hours. In with its litter and remove. general, give the first feed at 5 o'clock in the In using a second or third tier over the first, as morning and the last at 10 or 11 at night. Before C, C, C, C, Fig. 1, it is necessary to place each feeding, spread a net or paper over the worms beneath, on a couple of bars, B, B, B, B, cloth and place the leaves on it. About every two days, or boards to catch the leaves and litter from lift the net with the worms to a new frame and above. remove the litter. The space must be increased The utmost cleanliness being necessary, the as the worms grow, so as to avoid crowding. litter should be removed often, especially during They will need double space the second day. To the last three ages, as well as all dead and sick accomplish this, in feeding, when about half the
The consumption of food is enormous