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compared with the gorgeous plants with which we beautify our gardens; and in this respect they teach us not to overvalue mere external beauty, or despise anything, however humble, which God has in His wisdom created.

V.--THE PLANTS USED IN DYEING.

The clothing with which the plants of which we have been speaking furnish us, when not naturally white like the cotton plant, become so under the process of bleaching and washing. A moment's reflection will satisfy you how disagreeable it would be to us if we had no means of varying this colour. God has covered the earth with beauty : He has profusely decorated its surface with flowers of every imaginable shade of colour ; and He has given us eyes to see, and minds to appreciate the glorious hues of the sun-lit clouds, the empurpled mountains, and the green carpet of the earth. He has striped the tiger and the zebra : He has spotted the leopard : He has clothed the birds of the air with every variety of splendour, from the wondrous plumage of the peacock to the dazzling little vest of the humming-bird. The shells of the sea-shore are painted with daintiest care. Countless insects flutter like moving flowers, rivalling in beauty those over which they hover, or they move majestically along, glittering in burnished coats of mail, outshining the emerald and the ruby in the dazzling brilliancy of their hues. We see all these things, and when our eyes are trained to look lovingly on the works of God, they are a joy to us, and a never-ending pleasure. Having then this capacity of enjoying colour, how painful it would be to us if we were compelled to wear garments always of one hue, either of the undyed vegetable fibres, or of the uncoloured sheep's-wool of which our woollen cloths are made ! Happily the Creator, who has made all these things for our use, has gifted us with intellect and an ardent desire for knowledge, which are ever leading us on to explore the world, and to examine carefully all created objects ; and by the exercise of this intelligence, man has found out ways of transferring the colours of plants to his woven cloth. When he found that these colours faded too speedily, his busy mind would not rest until, by experiments, patiently and perseveringly conducted, he discovered the means of rendering them permanent. But all this has not been done at once ; century after century the search into the properties of things, as well as into the laws of nature, has been prosecuted, and even now, apart altogether from the love of knowledge for its own sake, our wants, as civilized men, require constant efforts of thought, if we would add beauty and variety to our manufactures.

1. Logwood.—One of the principal of our dye-stuffs is logwood, which is imported in the form of large rough blocks of a darkred coloured wood. They are pieces of the stem of a very fine large tree, which grows in the forests of South America, particularly about Honduras. When boiled in water, this wood communicates to the water its own dark-red colour ; and if a few drops of vinegar, or any other acid, be added, the red acquires a very bright hue. Red ink is made in this way, but it requires the addition of a little alum, or some other chemical substance to render it permanent. If instead of the acid, we put a little soda or potash into the water, it gives rise a dark blue or purple ; and by careful management, it may be made to give nearly every shade of these colours. This wood is very hard, and is cut into blocks with great difficulty. After these blocks are brought to this country, they are cut up or rasped very fine, in powerful mills constructed for the purpose.

So much is this wood used by our dyers, that our ships annually import from South America about 40,000 tons.1

2. Nicaragua Wood, &c.—Another dye, called Nicaragua wood, comes over in somewhat similar blocks. It gets its name from the fact of its being chiefly procured from the Republic of Nicaragua, in South America. This wood yields to the dyer delicate peach and cherry colours. That which is brought from Peru, however (called Lima wood, from the port at which it is shipped), yields finer shades. The inhabitants of those countries send us yearly more than 8000 tons of this wood. Two others are also sent from Brazil, but in much thinner pieces, and of lighter colour, owing to the outer part of the wood being yellowish. The inside, however, is red, like the woods of Nicaragua and Lima. One is called Brazil wood, the other, Braziletto; the latter being in pieces about the thickness of a man's wrist, the former as thick as the arm. These yield some very delicate tints of rose, lilac, and other hues. The vast forests of South America are very rich in useful plants, particularly in those suitable for dyeing.

1 When it was first brought over in Queen Elizabeth's time, this wood obtained such a bad character, owing to the ignorance and dishonesty of the dyers, that an Act of Parliament was passed to prevent its being used. Cloths were dyed with it, but the mode of fixing the colours being unknown, purchasers were disappointed at finding that they washed out. This raised a great outcry against the dyers who had sold them as fast colours. But in the course of time discoveries were made, which removed the difficulty, and logwood is now considered our most valuable dye-wood.

In addition to those mentioned, we have blocks of wood sent to us of an orange yellow colour, evidently parts of the stems of very large trees.

This is called Fustic, and is used for dyeing various shades of yellow and brown. This, too, is very extensively used, and our dyers now consume fully 10,000 tons annually.

3. Madder.—There is a little creeping plant called Madder, which is very common in the warmer parts of Europe and Asia, not only as a cultivated crop, but also as a weed. It is cultivated, to some extent, in Holland and Germany, and forms a very considerable article of trade. Its roots, which are about as thick as a blacklead pencil, and of a blood-red colour, are dug up and carefully dried, and packed into bags or bales for exportation : if ground before being sent to market, the powder is packed in very large casks. So important is madder, that it is extensively cultivated in almost every country suitable to its growth : we get madder roots whole from India, Turkey, Greece, Spain, and France; and ground madders, or madder roots reduced to a coarse powder, from Holland and Germany. The natural colour of the powder is the bright red, called Turkey red, but by the addition of various chemical compounds, almost every shade of red, purplish brown, purple, lilac, and even a lively rose colour, can be procured from it. It is so extensively used, that it employs many thousands of people in Glasgow, Manchester, and other large cotton-manufacturing towns, and scarcely a calico or muslin print is made without the aid of madder-root in some way or other for forming the pattern. Nearly 20,000 tons are used every year in this country alone, and it is also one of the principal dyes used in India, Turkey, and elsewhere. We thus see that the importance of this weed, humble as it appears, and which, if growing by the hedge-side, would scarcely attract a passing glance, can scarcely be overrated. Indeed, it is estimated that, in 1856, the manufacturers of Great Britain paid the merchants of other countries no less than £988,574 for this root alone in one form or other. What a lesson this teaches us ! The gaudy tulip will catch the eye, and call forth the praises of the uninstructed child ; but he who has learned that genuine worth is a higher quality, will rather be disposed to look with admiration upon this unattractive little weed, which is so useful to man, and affords employment to so many thousands of our fellow-creatures.

4. Indigo.—In India, in Egypt, and in Brazil, immense fields are covered with crops of a plant called indigo, somewhat like the tare of our farm-lands, but more erect and slender. It bears its little pea-shaped flowers in clusters, and though smaller, has a great resemblance to the pretty blue vetch which rambles through our hedges. When this plant is about to blossom, it is cut down and tied in bundles, which are quickly carried to large cisterns before the sun has time to wither them. When the cistern is nearly full, weights are placed on the bundles to keep them from floating, and water is let in until the indigo plants are completely covered. After the plants have been for some time infused, the water becomes yellow, and is drawn off into another cistern, and fresh water continues to be added until the plants cease to give it a yellow tinge. The yellow water is then beaten with poles, and violently stirred about ; an operation which, by causing the air to mix with it, changes the yellow to a deep blue, just as contact with the air changes the bitten part of an apple to a brown colour. The blue is heavier than the yellow, in consequence of the air which has been intermixed, and it consequently sinks when left at rest, depositing itself at the bottom in the form of a blue sediment. The water is then drawn off, and the sediment, which has solidified in the process of drying, is cut out in little square blocks, which, when perfectly free from moisture, constitute the Indigo of commerce. These blocks are packed into strong chests, and sent to this country, where indigo forms a most valuable addition to our dye-stuffs, giving various shades of blue and violet, and, when mixed in proper proportions with yellow, almost every shade of green. It is an expensive article, being worth from three to five shillings per pound ; nevertheless, we use more than 2000 tons, or 4,480,000 pounds of it annually.

5. Saflower.—Another very important plant to the dyer is the safflower, which, in the colour of its flowers, and the size of the plant, is like our garden marigold. A safflower field in full bloom must be exceedingly beautiful, and like a sea of gold. When in full blossom the harvest begins, the gatherers plucking the flowers, and pulling out their bright orange-red petals. These are then pressed into little cakes and dried, and sent from India to Europe packed in strong bales. There are two distinct colours in safflower, a bright crimson and a fine dark yellow, which can be separated by the chemist's art so as to be used, either singly or together, as the dyer wishes. This characteristic is not peculiar to safflower, for the same may be said of madder, which contains a mixture of bright red and purple : several other plants have more than one colouring principle. The crimson colouring material of safflower, called Carthamine, is very peculiar, for, when in any

considerable quantity, and dry, its surface assumes a peculiar metallic brilliancy and green hue, exactly similar to the burnished green of the wingcases of Rose-beetles. It is a very expensive material, and is used only in dyeing fine silks.

Were we to visit a dye-house, we should find very many other dyes used, according to the material to be coloured, the quality of the colour required, and various other circumstances. have now enumerated the principal vegetable dyes, and have shown how the wood of trees, the roots of weeds, the petals of flowers, and the colouring matter of other parts of plants may be turned to many

useful purposes, at the same time that they give the means of procuring profitable employment to many thousands of clever and industrious people.

But we

VI. THE MATERIALS USED FOR TANNING OR CONVERTING THE

SKINS OF ANIMALS INTO LEATHER.

Man in a savage state is content to clothe himself with the dried skins of the beasts which he kills for food ; but it is one of the first steps in human progress to seek a more agreeable covering, and this man finds chiefly in those vegetable fibres which we described in a former lesson. Skins, however, continued to be used for many purposes for which they were peculiarly suited; and, as mankind increased, the demand must have been so much extended, as to render it necessary to find some means of preserving the skins in such a way as to enable them to resist the action of damp and moth, which otherwise speedily attack and destroy them. This object is attained by tanning the skins, a process which we will endeavour to explain.

In the bark of certain trees, and in various plants, there is found a peculiar yellow substance called Tannin, very light, and of a bright shining appearance, in consequence of its being composed of small yellow crystals. This substance has the power of uniting with the skins of animals, and in this way, of so entirely altering

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