Page:Collier's New Encyclopedia v. 05.djvu/515

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LEAR 439 LEATHER LEAR, KING, a legendary King of Britain, who in his old age divided his kingdom between Goneril and Regan, two of his daughters, who professed great love for him. These two daughters drove the old man mad by their unnatural con- duct. Shakespeare made this story the subject of one of his plays. LEASE, the contract establishing the relation between landlord and tenant. LEASEHOLD, a dependent tenure de- rived either from a freehold or a copy- hold, and held by lease. Schemes for the enfranchisement of leaseholds (al- lowing persons having long leases of small portions of land a right to pur- chase the fee-simple) concern mainly building leases. LEATHER, the skins of animals chemically modified by tanning and otherwise, so as to arrest that prone- ness to decomposition which characterizes unprepared skins, and to give to the substance greatly increased strength, toughness, and pliancy, with insolubility and unalterability in water. Remains exist of tanned leather made in Egypt not less than 900 years b. C. There are three methods by which leather is pre- pared: first, and by far the most im- portant, with tan barks and other vege- table substances containing tannin; sec- ond, by tawing with alum, bichromate of potash, and other mineral salts; and third, by shamoying or impregnating the raw skin with oil. The skins of all ani- mals used for leather making consist chiefly of a fibrous gelatigenous sub- stance called collagen, which on being boiled forms the ordinary gelatin of commerce, with an interfibrous com- pound called coriin, insoluble in water, but which in common with collagen unites with tannin to form the insoluble and unalterable compound tanno-gela- tin, the chemical basis of tanned leather. The skins of all animals may be made into leather; but in practice the raw ma- terials of the manufacturer consist of the skins of certain animals which are reared and slaughtered primarily for other purposes, and of which the sup- ply is sufficiently large to form the basis of a great industry. Large skins, it may be remarked, such as those of oxen and horses, are in trade termed hides; those of calves, sheep, goats, and other smaller creatures are called skins. Of all leather-making hides the most important are those of oxen, which are primarily distinguished as ox, cow, and bull hides, and calf skins. Leading sources of sup- ply are Australia, the Cape of Good Hope, the River Plata and South America generally, and China and Japan. From the East Indies there come vast quantities of small hides termed kips, both salted and tanned. Buffalo hides are imported in large quantities from Singapore, Batavia, Bombay, Kurrachee, and Calcutta. Horse hides are brought in considerable quantities from South America. Sheep skins, from the vast quantities yearly available in nearly all parts of the world, are a most important source of leather. Goat skins and kid skins come from the Cape, the East In- dies, Asia Minor, and Switzerland; but many of the East Indian and Asiatic skins are when imported already tanned, and require only dressing. Other skins which have only a local or a limited market are the walrus, rhinoceros, and elephant, from which leather of great thickness, suitable for polishing wheels and other mechanical purposes is ob- tained; and hog or pig skin is an im- portant source of leather for saddle mak- ing and other purposes. The skins of various species of deer and antelope, por- poise and kangaroo, are also sources of leather; and from the Cape there are occasionally sent to the London market skins of the gnu and quagga. As sources of leather for fancy articles there may be mentioned the alligator (a leather now extensively imitated) , and certain snakes' and sharks' skins. Tanning. — The operations of tanning and the duration of the process vary very widely. Oak tannage is a very tedious process, and the common practice is now to hasten the completion of the operation by mixed tannage, in which more rapidly acting agents play a part. In the United States hemlock bark from Abies canadensis is the most important tanning material; and the mimosa or wattle barks of Austr?.lia are very largely used in the Bri^ sh colonies as well as in Great Britain. Standard ex- tracts containing a fixed percentage of tannin have also come into favor for rapid tannage. But, with all the devices which have been suggested, tanning is essentially a slow operation. The great amount of poor leather in the markets is due to hurried preparation and use of chemicals that injure the texture. In the treatment of ox hides for the production of, say, sole leather, the first object of the tanner is to clean and soften the hide. This is done by washing with water, and if necessary working the hide under stocks till the whole is uniformly soft and pliant. The unhairing and re- moval of the scarf skin is the next opera- tion, for which in English tanneries the hides are steeped in pits containing lime water, while in the United States the