posed of twelve membranous rings; the head is scaly, hard, and tapering; the mouth is horizontal; it has sixteen feet, six of which are placed in front, armed with claws, on the three rings nearest to the head; the other ten feet are placed behind, eight of which are on the sixth to the ninth, and two on the last ring. These feet may be termed holders. There is also a kind of tail on the upper part of the last ring but one.

At the end of the period above stated the worm's desire for food begins to lessen, though it continues to nibble the leaves, which it scatters about; its colour is now of a light green; it is very restless and uneasy, erects its head, and moves from side to side in a circular manner, seeking a corner where

it can commence its labour of forming its cocoon, before which, however, the body becomes firmer, more glossy, and somewhat transparent towards its head; it also lessens in size.

It may not be out of place to mention here from whence the silk proceeds;-The silk is secreted in the form of a fine yellow gum, in two long slender vessels, one on each side of the body. This silky material, when drawn from the orifices beneath the mouth, appears to be one thread, but is, in fact, composed of two fibres, which are extracted from the orifices, and brought together by means of two hooks placed in the mouth.

The worm, having fixed upon some corner that will suit its purpose, commences the labour by spinning thin and irregular threads, so as to support its future dwelling; it then forms upon these a loose structure of an oval shape, which is called floss silk; in the three following days it forms a firm and consistent yellow ball, the interior of which is smeared with a peculiar gum, so as to shield it against the rain and various changes of temperatures. The filament is not spun in regular concentric circles,

but in stops, going backwards and forwards with a sort of waving motion, which the worm effects by means of its fore feet, while it remains in the interior.

Isnard, an old author, affirms, that the length of the silk of one cocoon, when drawn out, will measure six miles, that is, 10,565 yards; but Count Dandolo says, the probable length is 625 yards; other authors state it to be about 400 yards; while Pullein says the average length is 300 yards. The latter author thus writes:-"There is scarcely any thing among the various wonders which the animal creation affords, more admirable than the variety of changes which the silkworm undergoes; but the curious texture of that silken covering with which it surrounds itself, when it arrives at the perfection of its animal life, vastly surpasses what is made by other animals of this class. All the caterpillar kind do, indeed, undergo changes like those of the silkworm, and the beauty of them in their butterfly state greatly exceeds it; but the covering which they put on before this change into a fly is poor and mean, when compared to that golden tissue in which the silkworm wraps itself. They, indeed, come forth in a variety of colours, their wings bedropped with gold and scarlet, yet are they but the beings of a summer's day; both their life and beauty quickly vanish, and they leave no remembrance after them; but the silkworm leaves behind it such beautiful, such beneficial monuments, as at once record both the wisdom of their Creator and his bounty to man."

The worm, having finished its cocoon, rests a while from its labour, and at the same time decreases in size and bulk; it then throws off its last skin, and undergoes its metamorphosis into a chrysalis, which is of a chestnut colour, and smooth. The time during which the insect remains in this state of lethargy is generally from fifteen to thirty days, as

it is influenced by the temperature of the climate in which this metamorphosis is about to take place, viz., in England it requires thirty days, in France twenty-one, in Spain and Italy eighteen to twenty, and in India only eleven days.

After the above stated periods the insect breaks through the upper end of the cocoon, by emitting a liquid from its mouth, which moistens the gum with which it has lined the interior of its chamber. After this operation it appears as the perfect insect, with four wings of a grayish white colour,with two trans

verse undulated bands on the fore and hind wings. The stationary and sluggish habits of these moths are not entirely owing, as is generally supposed, to the insect being confined within certain limits during the period of several generations; as these habits are also common to others of the same family, which are only found in certain local districts; and this proves that this valuable insect partakes of the same mode of life in the domestic as in the wild or natural state. Their life continues for the short period of two or three days, in which time they are wholly occupied in securing the continuance of

their kind. Various accounts are given as to the number of eggs which the female lays, some stating 250, while others mention 400 to 500 as the usual number.

CHAPTER V.

HISTORY OF SILK, &c.

History of its Fabrication-Several Kinds of Worms reared in India and America-The Silk Company-Culture of the Mulberry-tree-Laboratory—Air—Heat-Temperature-Light-Of

the Kinds of Silkworm-Eggs-Hatching-Space-FoodWeight and Length of the full-grown Worm.

It is allowed by all, that the silkworm and the mulberry-tree are indigenous to China, where the former is termed Se. According to the Chinese historians, one of their emperors ordered his wife to endeavour to rear the silkworm, for the purpose of making its industry available to man. After many fruitless attempts, she at last completely succeeded, and was enabled to fabricate from the raw threads stuffs which she afterward embroidered with images of flowers and birds. This invention, which the Chinese state as taking place 2,698 years before the Christian era, raised the emperess to the rank of a divinity, under the title of Spirit of the silkworm and of the mulberry-tree. From China the culture of the silkworm passed very slowly into Persia and India, and thence, though after the lapse of several centuries, into Europe. It is certain that prior to the time of Alexander the Great, silk was unknown in Greece; and it is probable that when that conqueror adopted the flowing robes of the Medes and Persians, he first became acquainted with silk. This commodity was unknown in the early times of the Roman republic; the victories of VOL. II.-H