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ELECTROTYPE

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entire subject, see Hastings' and Beach's General Physics. Read Faraday's papers, in Harper's Scientific Memoirs. Electron. (See ATOM.) Electrotype. The art of copying printing-type, wood-cuts, seals, medals, engraved plates etc. in metals, especially in copper, oy means of a galvanic current, is called electrotyping. The process, briefly, is this: An impression of the thing to be copied is first taken in gutta-percha, sealing-wax, fusible metal or any substance which, when heated, takes a sharp impression. While this impression—say in gutta-percha —is still soft, a wire is inserted into the side of it. As gutta-percha is not a conductor of electricity, it is necessary to make the side on which the impression is taken conducting, and this is done by brushing it over with plumbago by a camel's-hair brush. The wire is next attached to the zinc-pole of a weakly charged galvanic battery, and a copper-plate is attached by a wire to the copper-pole of the cell; or the required current may be supplied by a dynamo-electric machine, as is now usual. Then the impression of the plate to^ be copied is dipped into a copper-solution. The copper of the solution begins to be deposited on the impression, first at the black-leaded surface near the connecting wire, then gradually over the whole conducting surface. After a day or two by the old method — in a few hours now with the new inventions in electrical machines— the impression is taken out; and the copper deposited on it, which has formed a tolerably strong plate, can be easily removed by putting the point of a knife between the impression and the edge of the plate. On the side of this plate, next the mold, we find a perfect copy of the original woodcut. If a coin or medal is taken, we may proceed in the same way or take the medal itself and lay the copper on it. In the latter case, however, the first cast, so to speak, is negative; that is, showing depressions where the medal is raised; this negative can then be taken for a second copy, which will exactly resemble the original. See Electro-Metallurgy, by George Gore.

El'ephant, the largest of land-animals, with a long trunk or proboscis, with nostrils at its extremity and with two upper teeth developed into tusks. There are two 'kinds now living: the African elephant, inhabiting the greater part of Africa south of the Sahara, and the Indian, found in the forest-lands

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HEAD  OP   AFRICAN ELEPHANT

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of India and solrthea$tertt'v Asia, including the islands of Ceytott aad. Sumatra, These are distinct kinds. The African form is slightly higher, with a convex forehead and very large ears — about three and one half feet long by two and one half feet broad. Tusks are carried both by male and female. The Indian form has smaller ears, a concave forehead and tusks only in the male. Elephants may reach a weight of three or four tons, and a height of eleven feet or a little more. The famous Jumbo was eleven feet, two inches, and at the time of his death was not done growing. The trunk is an elongated nose and upper lip grown together. The nostrils are at the end, as is also a finger-like tip for grasping. It is very muscular and strong, and is put to many uses in feeding, drinking, spraying, lifting, etc. The tusks of the African elephant are of a better quality of ivory than those of the Indian. Large tusks weigh 150 pounds and may exceed that weight, but the average weight is about 28 pounds, and they sell for about $300 a hundredweight. Elephants have been so extensively hunted and killed for their ivory, that their number is being reduced. The Indian elephant is domesticated, and is used in lumberyards for piling lumber and other heavy work. It is ridden by native princes and their friends. A large saddle with a canopy, holding several persons, is strapped on the back, and the driver (mahout) sits astride the neck and uses a goad and hook in controlling the animal. Asian elephants are also put to other uses, but principally on state-occasions and in tiger-hunting. The hunters shoot from the backs of the elephants, while the natives beat up the jungle to drive the tiger into sight. Elephants live to an age of 120 years. In their native haunts they eat shoots and twigs of trees, various kinds of grass, bamboo, sugar-cane, reeds, etc. The food of the African elephant is of a coarser variety—- larger shoots, roots of trees and shrubs. The elephant also is fond of fruit. In captivity it is fed largely on hay and carrots. It has a long memory for friends and foes, revenging itself for tricks and insults. Asian elephants were used in war by ancient warriors. Egypt and Carthage domesticated the African elephant, and Hannibal used it in his wars. For extinct species of the elephant, see MAMMOTH and MASTODON. See Haider: The Ivory King.

.HEAD OF INDIAN ELEPHANT