Page:The New International Encyclopædia 1st ed. v. 12.djvu/67

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LEATHER.
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LEATHER.

be used in the manufacture of glue. The preliminary process of cleansing and depiling is performed as for skins that are to be tanned. After thorough cleansing, the pelts are steeped in a pit filled with lime and water, being taken out from time to time and drained on sloping benches. When removed finally from the lime-pit, the skins are worked with the knife, to render them more supple, and are then put into the branning mixture. This consists of bran and water in the proportion of two pounds of bran to a gallon of water. From this mixture they are transferred to an alum bath in a wooden tumbler or drum. For every two hundred skins some twelve pounds of alum and two and a half pounds of salt, with twelve gallons of water, are used. After remaining in this mixture about five minutes they undergo what is called pasting. The paste is a mixture of wheaten bran and sometimes flour and the yolk of eggs, which the leather almost completely absorbs. Lastly the skins are dried and examined, and if satisfactory are dipped into pure water, and worked or staked by pulling them backward and forward on what is called a stretching and softening iron and smoothed with a hot smoothing-iron.

Shamoying is effected by treating the skin with oil. After the skins have been thoroughly cleansed with lime, and then by a bran drench to remove the lime, they, while still wet, are oiled with fish, seal, or whale oil to which a slight amount of carbolic acid is sometimes added. The oil works into the skin, displaces all the water, and becomes united with the material, rendering its texture peculiarly soft and spongy. Wash-leather or chamois-leather is so prepared, and for this purpose the flesh halves of split sheepskin are chiefly used.

The skins which form the staple of leather manufacture are those of the ox, cow, calf, buffalo, horse, sheep, lamb, goat, kid, deer, dog, seal, hog, walrus, kangaroo, and alligator. The term pelt is applied to all skins before they are converted into leather. When simply made into leather in the state we find in shoe-soles, it is called rough leather; but if in addition it is submitted to the process of currying, it is called dressed leather. Hides are the skins of large animals, as horses, cows, and oxen. The complete hides when rounded, with the cheeks, shank, etc., cut off, are called butts; the pieces cut off constitute the offal. Skins are all the lighter forms of leather, as sheep, goat, deer, including the skins of fur-bearing animals in which the fur is retained. Kips are the skins of yearlings and animals larger than calves. Alligator leather is chiefly used for small fancy articles. Only the skins of young alligators are used, and of these the backs are thrown away as too horny. Walrus and hippopotamus hides are tanned in considerable numbers for the use of cutlers and other workers in steel goods; buffing-wheels are made of them, often an inch thick, which are of great importance in giving the polish to metals and horn goods. Hog-skins are used for the manufacture of saddles and fancy articles. Dog-skins are used for gloves. The ‘grain leather’ of commerce is leather that has been made from the hides of neat cattle, split so thin by the splitting-machine as to be suitable for the same uses as are goat, calf, and various other skins which it is made to imitate.

Morocco leather, formerly an article of import from the Barbary Coast, is now prepared in the United States from goatskins; sheepskins are also used for imitation. It is always dyed on the outer or grain side with some color, and the leather-dresser in finishing gives a peculiarly ribbed or a roughly granulated surface to it by means of engraved boxwood balls which he works over the surface. Morocco has been largely superseded by glazed kid.

Russia leather is much valued for its aromatic odor, which it derives from the peculiar oil of the birch-bark used in tanning it. The fact that this odor repels moths and other insects renders this leather particularly valuable for binding books; a few books bound in Russia leather being effective safeguards against insect enemies in a library. It is also said to destroy or prevent the vegetable evil called mildew, to which books are so very liable.

Japanned leather, varieties of which are known as patent and enamel leather, which is largely used for fancy work and for shoes, is said to have been made in America as early as 1818, by Seth Boyden, of Newark; but it is only within recent years that the American product has approached in excellence that made in Germany and France. The European method of manufacture is described substantially as follows in the Twelfth United States Census Bulletin on the Leather Industry (No. 195: Manufactures, vol. ix., pt. 3): In the preparation of enameled leather, a foundation coat of lampblack mixed with linseed oil has been laid on the flesh side, since the infancy of the industry in Europe. Successive coats of this mixture are applied, the skin being allowed to dry and the surface ground down with pumice-stone after each coat. Then the skins are blackened again with a fluid black mixed with turpentine, and hung up to dry again. After the skins have been allowed to settle, being laid in a pile for about a month's time, or longer if possible, the leather is tacked on to a frame and receives a brush coat of varnish. A baking follows in an oven of moderate heat. The temperature is gradually raised and the baking continued three days. Exposure to the sun for ten hours completes the process. Recently American manufacturers have been making patent leather from chrome-tanned skins. The product is quite different, as is also the process employed. The leather is softer, more flexible, and takes a less brilliant polish than that made from bark-tanned leather, but it is much less likely to crack and is more suitable for shoes than the brittle and inflexible leather made by the older process.

Cordovan is made from horse-hide and is so called because it was first successfully tanned in Cordova, Spain. Most of the hides of commerce are taken from the wild horses of certain parts of South America. A portion of the skin, oval in shape, taken over the rump, about three feet long and half as wide, is all that is used for leather. Its distinctive quality is that it is nearly water-proof.

Statistics. According to the United States census for 1900, there were in this country, at the close of the century, 40,751 establishments devoted to various branches of leather manufacture. The amount of capital invested is given as $173,977,421 and the annual value of the product $204,038,127. Of this product leather goods to the value of $27,293,019 were exported, while $6,773,024 worth of leather goods were im-