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long in water as the best oak; and the bark is tough and fibrous, and may be made into strong and dura ble mats and baskets.

The greatest value of the mulberry-tree in the arts consists in its being the favourite food of the silkworm. That insect, and this use of the mulberrytree, were both unknown to the Greeks and Romans; though there is every reason to believe that they

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were then, and perhaps earlier, known to the Chinese, and possibly to some of the other inhabitants of central and southern Asia.

The rearing of silk-worms, and the manufacture of silk, are said to have been introduced into the Western world in the sixth century of the Christian era. About the year 550, two monks, natives of Persia, while employed as missionaries to the Christian churches in India, are said to have penetrated as far as China, where they acquired a knowledge of the rearing of the silk-worm, and the working of silk. Upon their return, they explained to the Greek emperor at Constantinople the nature and importance of those operations, and undertook to bring to that capital as many silk-worms as should suffice for esta

blishing and supplying the manufacture. They were immediately sent off, and soon returned, with the eggs of the silk-worm concealed and preserved in a hollow cane: these eggs were hatched by the heat of a dunghill. The attempt succeeded; the worms were fed with the leaves of wild mulberry trees; they multiplied rapidly; and the produce of their labours proved to be as good silk as that which had been made in the East.

The animal by which silk is originally made is a species of moth (Phalena Mori). When perfect, or in the winged state, it is of a whitish colour, with a pale brown line across the upper wings, and displays in itself none of that lustre which its labours produce. The caterpillar, in which state it spins the silk, and is thence called the silk-worm, is about three-quarters of an inch long, of a yellowish grey colour; it feeds very voraciously on the leaves of the black and white mulberry tree indiscriminately; and it will also feed upon lettuce and some other plants. For about six weeks, the silk-worm remains in the caterpillar or larva state, changing its skin four times during that period, and ceasing to feed for a short time previous to each change. full grown, it eats no more, but, choosing a convenient place, begins to envelop itself in silken fibres; and it continues this operation till it has spun an oval case or ball of yellowish silk, about the size of a pigeon's egg, in which it remains as a chrysalis for about fifteen days, at the end of which it gnaws through the end of the silken ball, and comes out a winged moth, to deposit its eggs for a fresh generation, and very soon after to die.

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Those who cultivate the worm for silk do not suffer it to reach this last stage, because the silken fibre would be cut into small pieces by the opening at which the moth escapes. When the whole quantity of silk

is formed, they destroy the chrysalis by means of heat.

Previous to the time when the two missionaries brought the eggs of the silk-worm from China, and succeeded in obtaining raw silk at Constantinople, silk was a very costly article, the price in Rome being an equal weight of gold. But the number of worms augmented rapidly, and Greece, more especially the Morea, produced an abundant supply. The conquest of Constantinople by the Venetians, in 1204, led to the introduction of the article into Venice, from which, in the course of a short time, it extended to Genoa, and other parts of Italy. Henry IV. was anxious to introduce the silk-worm into France, and he took some very efficient measures to advance that object; but his success was not equal to his wish. Colbert, in the reign of Louis XIV., was the first who added it to the productive wealth of that country, upon a large scale. James I. was desirous of introducing it into England, and there have been many trials since; but, though these have promised to be successful, they have not been prosecuted, probably because the culture is better adapted to warmer skies and a less laborious population. When the mulberry is cultivated for the rearing of silk-worms, it is not allowed to grow to a timber-tree. The young shoots are prepared for that purpose; and, therefore, in China, the trees are either cut down altogether every third year, or they are kept low by pruning. When the leaves of the mulberry fail, or are deficient, in China, those of the ash are said to make no bad substitute. Some varieties of the ash have certainly this much in common with the mulberry, that they do not expand their leaves till the season be far advanced, seldom till the middle of May, and very often not till the end of that month. It is stated that the Chinese dry the mulberry leaves in the sun,

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and keep them in close-stopped vessels, for the food of the silk-worm, if it be produced before the young leaves of the tree are ready for its support. When cultivated for its fruit, the mulberry, unlike most other fruit-trees, produces fruit in greater abundance and of larger size as it gets older; and, as its dense and dark foliage forms a fine contrast with trees of more airy form and lighter hue, it is a very ornamental tree.

The Paper Mulberry (Broussonetia papyrifera), is a native of China and Japan, the South Sea Islands, and some parts of America. It does not attain a very great height, but it shoots vigorously, and is a very branchy tree. Its fruit is black, purple, and sweet, but small-not larger, in general, than a common pea.

It is cultivated in Japan for the manufacture of paper; and from this circumstance it gets its specific name. For this purpose it is raised in beds,

as osiers are cultivated with us for the use of the basket-maker and the cooper. When the leaves have fallen off, that is, about the month of December, the shoots are cut down, divided into lengths of about three feet, bound into bundles, placed upright and close together in a copper, and boiled till the bark be completely loosened from the wood. Should they be dry before being subjected to boiling, they are prepared for that operation by maceration in water for twenty-four hours. After the rods are cold, the bark is divided lengthwise by a knife, stripped off, and dried for use. When to be used, it is put into water till it is so much soaked that the external and coloured part of the bark can be separated. That being done, the bark is sorted, the strongest being set apart for the best and whitest paper, and the weaker for that of inferior quality; while of the refuse they make a very coarse brown paper. The sorted bark is

then boiled till it becomes tender, that is, till it easily separates with the fingers; and then it is washed for a longer or shorter time, according to the quality of paper wanted. If strong writing paper, the washing must be moderate; but if the colour is to be very delicate, and the texture soft and silky, the washing must be more prolonged. When properly washed, it is taken to a table, and there reduced to a pulp, by beating with wooden mallets. When sufficiently reduced, it is brought to the requisite consistency with water; rice-starch, and the mucilaginous infusion of manihot-root (Hibiscus manihot), are added by way of size; and then the sheets of paper are formed one by one upon a table, collected into heaps, and pressed by a weight.

The same bark is used by the people of many of the South Sea Islands in the manufacture of their finer cloths, more especially those that are to be dyed. They make a coarser but stronger cloth of the bark of the bread-fruit tree, and also of that of another tree resembling the wild-fig of the West Indies. The paper mulberry will grow in England, but the cultivation of it would not, probably, be attended with much profit. There can be no doubt, however, that if proper attention were paid to the subject, excellent paper might be made of the inner bark of many of our native timbers, the bark of which is now used merely for fuel, or thrown away.

The fustic mulberry (Morus tinctoria) is a native of many parts of South America (especially Brazil) and the West India Islands. It grows to be a very large and handsome tree; and the timber, though like most other dye-woods, brittle, or at least easily splintered, is hard and strong. It is, however, chiefly used as an ingredient in dyeing yellow; and a great deal of it is imported into Europe for that purpose under the name of fustic.

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