Page:The New International Encyclopædia 1st ed. v. 14.djvu/640

* NICKEL. 546 NICOLA. metallurgical products uickol may be extracted as well as from the ores. The prineipal ores from wliieh iiiekel is extracted arc the sulpliur com- pounds and the silicates. The chief sulphur com- pounds are the nickel pyrites of iron and copper, of which one of the most notable deposits is at Sudbury, Canada. The Su<lhury ores are the principal source of the world's nickel supply. The extraction of nickel is performed by (1) the dry metliod, (2) the wet method, and (3) eleetro-metallurgically. The dry method is the one chietly used to extract the metal from the ores, the use of the wet method and electro- metallurgical processes being confined almost entirely to extraction from metallurgical products and the matte and spciss resulting from the dry processes. Most allcntion will therefore be given to the dry method of extraction as applied to the principal ore of nickel; that is, the com- bined nickel, iron, and copper pyrites. In smelt- ing these ores in the dry- way-, after getting rid of the ganguc, the metallurgist is chiefly concerned with the separation of the nickel from the sulphur, iron, and, in most cases, from the copper also. When no copper is present the process becomes simple. Considering first ores free from copper, the task is to get rid of the iron and sulpluir. The first operation consists in roasting the ore, which converts the metallic sulphides into a mixture of oxides, sulphates, and undeconiposed sulpliides. The roasted ore is then smelted in a shaft furnace with coal and siliceous matter, which removes the great bulk of the iron as slag, leaving a matte consisting of sulphide of nickel mixed with a small proportion of iron sulphide, (ienerally, to get a matte rich enough in nickel for the succeeding Qperations, these roasting and smelting processes are re- peated one or more times. The raw nickel matte is next submitted to an oxidizing fusion in hearths, reverberatory furnaces, or converters to remove the remaining iron, leaving nickel sul- phide. When copper is present in the ores as well as iron, the iron is removed exactly as before, the resilt being, however, a matte of nickel sulphide and copper sulphide nii.xcd. This matte may lie oxidized by roasting and then smelted to produce a nicl«'l-copper alloy, or to secure nickel alone the matte is smelted with a flux, which removes the copper, or is treated with ehemical.s, which permit the separation of the copper. This latter method is the chief use made of the wet method of reduction, which, as previously stated, is used mostly for reducing the mattes, speiss, and slags resulting from the smelling process. As in wet methods of extrac- tion generally, the process in the ease of nickel consists in dissolving the metals from the matte, etc., by acids, and then in i>recipitating sepa- rately the various metals from tliis solution. The nickel compounds resulting from the proe- e.sses mentioned are reduced to metallic nickel by smelting in crucibles with carbon. See Dr. Carl Schnablc's Handbook of MrlnUurqil (New York. ISPS). NICOBAR (nlkAblir') ISLANDS. .V group of islands in the Indian dccan beginning I.IO miles northwest of Sumatra and stretching northwestward for 200 miles (Map: French hi- de China, n fl). They form with the .Andaman Islands to the north of them the northern ex- tension of the great chain of islands of which Sumatra and Java are the principal members. The group consists of 19 islands, of which 12 are inhabited, the largest being Lireat and Little Xicobar in the south, Camorta in the centre, and Car Xicobar in the north. The area of Great Xicobar, the largest, is 337, and of the whole group ti84 square miles. The southern islands are mountainous and covered with dense forests; those in the north are low, less fertile, but sujiporting large numbers of cocoa-palms. The climate is hot, humid, and very unhcalthful for Europeans. The X'icobarese are classed with the Selungs of the Mergui Aichipelago as Indone- sians. The inhabitants of the smaller islands and of the coast of (!reat Nicobar have inter- mixed with Malays. In all probability they be- long originally to one of the i)riniitive stocks of Farther India (proto-Malay ? i with Xegrito and Malay admixtures. The northern X'icobarese are monogamous and value chastity very highly. In 1901 the inhabitants munbered (i310. They are chiefly supjiorted by their large trade in cocoaiuits and copra. Formerly they were en- gaged in piracy and wrecking, but have been peaceful since the British occnpation. The islands are, together with the Andamans, gov- erned by a Britisli chief conuuissioner. The British Covernment agent resides at X'aneowry Harbor, where there is a line landlocked harbor between Camorta and Xancowry islands. The Xicobar Islands were settled by Denmark in 1756, but her attempts at coloni;:ation were unsuccess- ful, and she abandcmed them in 1848. In 1869 they wore aiinexid by Great Britain. NICOBAR PIGEON. A large and very beau- tifil ground-feeding pigeon of the East Indies {('tilaiHis yicuhtiric(i) . which is remarkable for the elongated feathers that mantle the neck, and for its very wide distribution over the Polynesian region. Consult Wallace, Mala;/ Archipelago (Xew York, lSti9). NICODE'MUS (Lat., from Gk. NikW,^i, y Ikuili')ii(is) . A Jew described in the Gospel of John as a Pharisee and menil)er of the Sanhedrin, who came to Jesus secretly and by night at .Terusalem (.John iii. 1 sqq.). He put in a plea for a hearing for .lesus when the Pharisees would have conilenuu'd Kim without allowing Him to plead (.lohn vii. 50) ; and he bore a part with .Joseph of Arimatlnva in burying the body of .Tesns (.Tohn xix. 39). He disappears from the Xew Tes- tament after the burial. In an apocryphal book, the Gospel of Xicodcmus, or Acts of Pilate, the few facts recorded in the Gospels are elaborated and commented on at considerable length, evi- dently with no basis of historic truth behind them. See AP0CRT>II.. NICOL, nik'ol, Erskine (1825-1904). A Scotch painter, liorn at Leith, near Kdinbiirgh. He studied at the Trustees' Academy, Kdinliurgli, and then went to Dublin, where he tauylit and painted portraits. In IS.iO he was elected asso- ciate of the Royal .ca3 went to live in London. His works are genre, generallv of Irisli subjects, and many of them are well known in the I'nifed States throiigh engravings. .Among the best known are "Paddy's Mark," in the Corcoran Gallery, Washington; "Paying the Hint,"' in the Vanderbilt Collection, X'ew York. NICOLA, Lewis I 1717-c.1S07). An Ameri- can soldier, born in Dublin, Ireland. He became