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on the tenth day it shall have reached eighty-two degrees, which point must not be exceeded. The degree of warmth required for hatching the eggs of silkworms depends very much, however, upon the temperature to which they have been exposed during the preceding winter. It is, therefore, important that this point should be considered, so as to avoid premature hatching on the one hand, and too great a retarding on the other, which would follow if the eggs had been exposed to any severity of cold.

When the eggs assume a whitish color, it is a sign that they are about to be hatched; and now, by the aid of a magnifying glass, the worms may be seen formed within the shells. Sheets of white paper, abundantly pierced with holes, or otherwise pieces of clear muslin, should now be placed over the eggs, covering them entirely; when, as the worms come forth, they will climb through to the upper surface of the paper or muslin.

To collect the worms for the purpose of conveying them to the rearing-house, small twigs of mulberry, with very few leaves, are placed on the paper. On these leaves the newlyhatched worms immediately fix, and fresh twigs being constantly supplied to meet the wants of the continually increasing number of worms, the whole may be readily collected. When their removal to any considerable distance is necessary, this is easily and safely performed by placing the sheets of paper and mulberry twigs in boxes or well-lined baskets, using every precaution to exclude the external air from the now delicate brood. The worms should be removed only in fine weather, and during the warmest part of the day, and they should be supplied with leaves for their consumption while on the road.

The apartment wherein the newly-hatched worms are placed must be dry and warm, with its windows opening on opposite sides, that perfect ventilation may be obtained when desirable. The room should be furnished with a stove, and thermometers must be provided, that the temperature may be precisely regulated. Wicker shelves are usually placed around at convenient distances, and are lined with paper: on these the worms are placed. The greatest precautions must be taken to prevent the intrusion of rats and mice, as well as many of the insect tribe, as these are more or less destructive to silkworms. Smoke, and bad smells, are likewise considered prejudicial, and must be avoided.

All writers on the treatment of these insects agree in recommending, that worms which are not hatched at the same

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The upper slide a is of paper, and designed to receive the newly-hatched worms. The two slides, b b, are formed of catgut, the threads of which are about one tenth of an inch apart: these are for the insects in their second and third ages. The five slides c c are of wicker-work or netting, and are appropriated to the insects in their more forward stages. Beneath each of the drawers, with the exception of that marked a, other slides of paper are inserted to receive the litter of the worms, which, by this means, may be frequently removed without occasioning any disturbance to the insects. These must not be retained in the upper drawers bb after they have become so large that their litter will not fall through the catgut bottoms: at this time they must be transferred to the wicker or netting slides, which, the inventor imagined would, from their greater number, offer space enough for the accommodation of as many full-grown caterpillars as the upper drawer would contain of those newly hatched. Under this arrangement the litter may be removed as often as the worms are fed.

It has been computed, that three square feet of surface afford ample space for the worms proceeding from an ounce of eggs, until the period of their first sickness is passed; and that this space should be multiplied thrice at each succeeding age. Count Dandolo considered that silkworms would be injuriously crowded in these dimensions, and recommended, that eight square feet should be allotted to the worms during their first age; fifteen feet for the second age; thirty-five feet for the third; eighty-two and a half feet for the fourth; and about two hundred feet for the fifth age. According to these proportions Mr. Swayne's apparatus is very imperfect, but this defect may easily be remedied in practice.

The mulberry leaves given to the newly-hatched brood should be young and tender, and chopped into minute portions. These should be strewed evenly over the whole space of the shelves, that there may not be any unnecessary crowding of the insects in one spot. It is indeed advisable, when as they sometimes will the worms get heaped upon one another, that a leaf should be presented over them; to this some will quickly attach themselves, and may then be removed to a less crowded situation.

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The worms proceeding from one ounce of eggs will consume six pounds of chopped leaves before their first moulting. Their second age is of shorter duration, but the greater size of the worms requires a more abundant supply of food; and eighteen pounds of leaves, chopped less finely than be

fore, must be given, during its continuance, to the same number. In the third age, sixty pounds of leaves, still a little chopped, must be given; one hundred and eighty pounds will be consumed during their fourth age; and in their fifth and longest age, one thousand and ninety-eight pounds of leaves are devoured by these insects, which, when hatched a few weeks before, weighed less than an ounce.

These quantities are stated on the supposition that the worms are uniformly healthy. If many of them should die in the intermediate time, the weights mentioned will be in excess. On the other hand, if the season should be wet, the leaves will not contain the usual nourishment, with reference to their weight, and more must be given; whereas, if the season should prove more dry than ordinary, the nutriment in the leaves will be greater, and the quantity given may be diminished with advantage. The skill of the cultivator is shown by the weight of silk obtained in proportion to the leaves consumed; and his judgment is tasked to apportion these according to their nutritive properties. There will be no real economy in keeping the consumption of food too low: this, however, is not a common fault, and evils occur much more frequently from over-feeding and waste of leaves.

The worms should be fed with regularity four times a day; and intermediate repasts may be occasionally given, where their appetites appear to be increased in voraciousness. The advantage of chopping the leaves for young worms consists in the economy it introduces. Many thousand insects may, by this means, feed simultaneously upon a few ounces of leaves; whose fresh-cut edges seem better adapted to their powers when newly hatched. If the leaves were given to them whole, a much greater number must be supplied than would be consumed while their freshness lasted, and great waste would be the consequence. The worms will always quit stale leaves for those which are newly gathered. Availing themselves of this fact, some persons provide wire-bottomed frames, which they cover with fresh leaves, and lower them within reach of the worms. These instantly make their way through the reticulations of the wire, and fixing upon the leaves above, the frame may be raised and the litter removed without touching the worms, which might be injured by even the gentlest handling. This plan, as it occasions more trouble, does not appear so eligible as that of Mr. Swayne.

When the silkworms give indications that they are about to spin, little bushes must be provided for the purpose. These

may be of broom, heath, clean bean-stalks, or, in short, any bush or brushwood that is tender and flexible. These should be arranged upright in rows between the shelves, with intervals of fifteen inches between the rows. The bushes should be so high as to be bent by the shelf immediately above into the form of an arch. They should be so spread out, that a supply of air should freely reach every part, and ample space should be afforded for the worms to fix themselves and spin; otherwise, there is great hazard of their forming double cocoons, in which two worms assist in the preparation of one dwelling for both the silk in these is so much less adapted to the purposes of the reeler, that a double cocoon is worth only one half the price of a single one. Inattention to this point is very common, and occasions constant losses. When the twigs already erected appear to be adequately furnished Fig. 6.

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with worms, other similar hedges should be formed, parallel to the first. The spaces between the shelves will thus present the appearance of small avenues or arbors covered in at the top.*

The worms at this time require much careful watching, and occasional assistance must be afforded to those which are sluggish, that they may find an eligible spot for forming their Cocoons. Those worms which appear still inclined to feed must be supplied with leaves: so long as the slightest inclination for food remains, they will not attempt to form their cocoons. It will sometimes happen, that even after they have climbed among the branches for the purpose of spinning, they will again descend to satisfy their last desire for food.

* Note X.

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