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CHAPTER XXIII.

LEATHER.

Ir is interesting to speculate how prehistoric man came to use the skin of the beasts of the field for warmth and shelter. Originally no doubt, and for untold centuries, the use was confined to the hairy, undressed, fresh, or dried skins, known as pelts. Then came the use of better tools. The garments have perished, but the tools of stone and of bronze survived, which, when compared with those employed among the earliest historic tribes of men, were found to be adapted to cut and strip the hairy covering from the bodies of animals, and clean, pound, scrape and otherwise adapt them to use.

And ever since the story of man began to be preserved in lasting records from farthest Oriental to the northernmost limits of Europe and America, memorials of the early implements of labour in the preparation of hides for human wear have been found. The aborigines knew how to sharpen bones of the animals they killed to scrape, clean, soften or roughen their skins. They knew how to sweat, dry, and smoke the skins, and this crude seasoning process was the forerunner of modern tanning. But leather as we know it now, that soft, flexible, insoluble combination of the gelatine and fibrine of the skin with tannic acid, producing a durable and imputrescible article, that will withstand decay from

the joint attack of moisture, warmth and air, was unknown to the earlier races of men, for its production was due to thorough tanning, and thorough tanning was a later art.

When men were skin-dressed animals they knew little or nothing of tanning. Tannic acid is found in nearly every plant that grows, and its combination with the fresh skins spread or thrown thereon, may have given rise to the observation of the beneficial result and subsequent practice. But whether discovered by chance, accident or experience, or invented from necessity, the art of tanning should have rendered the name of the discoverer immortal. The earliest records, however, describe the art, but not the inventor.

From the time the Hebrews covered the altars of their tabernacles with rams' skins dyed red, as recorded in Exodus; when they and the Egyptians worked their leather, currying and stretching it with their knives, awls, stones, and other implements, making leather water buckets, resembling very much those now made by machinery, covering their harps and shields with leather, ornamental and embossed; from the days of the early Africans, famous for their yellow, red and black morocco; from the days of the old national dress of the Persians with their leather trousers, aprons, helmets, belts and shirts; from the time that the ancient Scythians utilised the skins of their enemies, and Herodotus described the beauty and other good qualities of the human hide; from the early days of that peculiar fine and agreeable leather of the Russians, fragrant with the oil of the birch; from the days of the white leather of the Hungarians, the olive-tanned leather of the Saracens; from the time of the celebrated Cor

dovan leather of the Spaniards; from the ancient cold periods of the Esquimaux and the Scandinavians, who, clad in the warm skins of the Arctic bears, stretched tough-tanned sealskin over the frame work of their boats; from the time of the introduction of the art of the leather worker to the naked Briton, down to almost the nineteenth century, substantially the same hand tools, hard hand labour, and the old elbow lubricant were known and practised.

Hand tools have improved, of course, as other arts in wood and iron making have developed, but the operations are about the same. There were and must be fleshing knives to scrape from off the hide the adherent flesh and lime, for this the hide is placed over the convex edge of an inclined beam and the work is called beaming; the curriers' knife for removing the hair; skiving, or the cutting off the rough edges and fleshy parts on the border of the hide; shaving and flattening; the cutting away of the inequalities left after skiving; stoning, the rubbing of the leather by a scouring stone to render it smooth; slicking, to remove the water and grease; or to smooth and polish, by a rectangular sharpened stone, steel or glass tool; whitening, to shave off thin strips of the flesh, leaving the leather thinner, whiter and more pliable; stuffing, to soften the scraped and pounded hides and make them porous; graining, the giving to the hair or grain side a granular appearance by rubbing with a grooved or roughened piece of wood; bruising or boarding to make the leather supple and pliable by bringing the two flesh sides together and rubbing with a graining board; scouring, by aid of a stream of water to whiten the leather by rubbing with a slicking stone or steel.

The inventions of the century consist in labour

saving machinery for these purposes, new tanning and dressing processes, and innumerable machines for making special articles of leather.

As before stated, the epoch of modern machinery commenced with the practical application of water power to other than grinding mills, and of steam in place of water, contemporaneously with the invention of spinning and weaving machinery in the last half of the eighteenth century. These got fairly to work at the beginning of the century, and the uses of machinery spread to the treatment of leather. John Bull was the appropriate name of the man who first patented a scraping machine in England, about 1780, and Joseph Weeks the next one, some years later.

One of the earliest machines of the century was the hide mill, which, after the hand tools had scraped and stoned, shaved and hardened the hides, was used to rub and dub them, and soften and swell them for tanning. Pegged rollers were the earliest form for this purpose, and later corrugated rollers and powerworked hammers were employed. Hundreds of hides could be softened daily by these means.

Then came ingenious machines to take the place of the previous operations of the hand tools,-the fleshing machine, in one form of which the hides are placed on a curved bed, and the fleshy parts scraped off or removed by revolving glass blades, or by curved teeth of steel and wood in a roller under which a table is given a to-and-fro movement; tanning apparatus of a great variety, by which hides, after they are thoroughly washed and softened, and the pores opened by swelling, are subjected to movements in the tanning liquor vats, such as rocking or oscillating, rotary, or vertical; or treated by an air

exhaust, known as the vacuum process; in all of which the object is to thoroughly impregnate in the shortest time all the interstices and pores of the skin with the tannic acid, by which the fibrous and gelatinous matter is made to combine to form leather, and by which process, also, the hide is greatly increased in weight.

Reel machines are then employed to transfer the hides from one vat to another, thus subjecting them to liquors of increasing strength. Soaking in vats formerly occupied twelve or eighteen months, but under the new methods the time has been greatly reduced. And now since 1880, the chemists are pushing aside the vegetable processes, and substituting mineral processes, by which tanning is still further shortened and cheapened. The new processes depend chiefly on the use of chromium compounds.

Then came scouring machines, in which a rapidly revolving stiff brush is used to scour the grain or hair side, removing the superfluous colouring matter, called the bloom, and softening and cleansing the hide; the slicking or polishing machines to clean, stretch and smooth the leather by glass, stone, or copper blades on a rapidly-moving belt carried over pulleys; whitening, buffing, skiving, fleshing and shaving machines, all for cutting off certain portions and inequalities of the leather, and reducing its thickness.

In one form of this class of machines an oscillating pendulum lever is employed, carrying at its end a revolving cylinder having thirty or more spiral blades. The pendulum swings to and fro at the rate of ninety movements a minute, while the cylinder rolls over the leather at the rate of 2780 revolutions per minute. Scarfing, skiving, chamfering, bevelling,

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