IRON.
Mars of the Alchemists. Ferrum, . . . LAT.
Hedeed, . . . ARAB. I3asi, Besi, . . MALAY. Than, . . . . Bunn. Ahan, . . . . PERS. Tieh, Tee, . . CHIN. Zelazo, POL Jern, . . DAN., Sw. Aos-panah, . . PUSHT.
Yzer, Jizer, . . . DITT. Scheleso, . . . Rms.
Fer, Fit Ayas, Hyam, . SANBK.
Eisen, GER Yakada, . . . SINGH.
Ais, GOTHIC. Hisao, Sr Sideros, On Irmbu, TAM Loha, . . . . IIIND. Inumu,. . . TEL.
Ferro, . . . IT., Pon. Deyrnir, Timer, TURK.
Iron when found native is supposed to be generally of meteoric origin, but extensively in combination with oxygen or sulphur, as a salt . of various acids, as carbonate, sulphate, etc., mixed with earths or other metals.
The iron of commerce is extracted from iron ores. Some of the oxides, as magnetic and spe cular iron-ore, are heated only with charcoal, as in Sweden, Russia, and the E. Indies, when the carbon combining with the oxygen the iron is set free and melted. The carbonate, iron pyrites, clay iron-ore, red and brown hiematites, and spathes° iron, are first roasted, and then exposed to a fierce heat in contact with charcoal, coke, or small coal, and a flux, either lime or clay, accord ing as the ore is argillaceous or calcareous. These earthy matters become vitrified, and form a slag at the surface, while the heavy particles of iron, falling down, run out by a hole at the bottom into moulds, and form pig or cast iron. This is still impure, from the presence of charcoal, sulphur, and portions of silicon and aluminum. It is again twice fused in the refining and puddling furnaces, and exposed to the influence of a current of air at a high temperature, when the whole of the charcoal and sulphur are burnt out, and the other impurities form a slag at the surface. The metal is taken out, beaten or pressed, and then drawn into bars, which form the malleable or wrought iron of commerce.
Iron has long been known in India. From a passage in Kalidasa's drama of the Hero and the Nymph (p. 218), it is clear that the art of welding it was known to the early Hindus.
' You tell me, gentle Nymph, your fair friend pines With amorous passion. But you do not see The ardour that consumes this heart for her. Alike our glowing flame. Then quickly aid Our union to cement, as close combines Iron with iron, when each fiery bar With equal radiance glows.' The iron-smelters of India are low caste, and humble, poor people. They have small clay fur naces, with charcoal for fuel, and the blast is caused by foot or hand bellows of sheep or goat skins, or even of leaves. The smelting process lasts from 6 to 10 hours, but at 3 or 4 separate charges, at the end of which time from 10 to 20 lbs. weight of iron is produced.
Iron-ores abound in almost every district of India, and the prevailing ore is the oxydulous iron, often magnetic, andwith polarity; but specu lar iron-ore, haematite, clay iron-ore, and sulphuret of iron also occur abundantly. Many of the ores are noted for their singularpurity, especially the magnetic oxides. Some are distinctly titaniferous, being in this respect similar to the Taranaki iron sand of New Zealand. But the bulk of the ores of Beypur, Salem, Palamcottah, Penatur, Puducottah, are. rich magnetic oxides, and when freed from earthy matter, and ready for the blast furnace, contain about 72 per cent. of iron. They are found in mountain masses, and are obtained by quarrying with a crowbar. They are quite free from sulphur, arsenic, and phosphorus, and upon a large average have been found to yield 68 per cent. of metal in the blast furnace. The Punpara and Honore ores were used for the production of steel by the Bessemer process.
The plan adopted for the production of Indian cast-steel at the Beypur works, by the Bessemer process, was similar to that pursued in Sweden, but differed essentially from the Sheffield method. At Sheffield and elsewhere in Great Britain, where the process was in operation, pig-iron was melted in a reverberatory furnace, and run thence into the converter or Bessemer vessel, which was mounted on axles. But in Sweden, and at the Beypur works in Madras, the crude metal was run direct from the blast furnace into an ordinary founder's ladle, raised to a sufficient height by means of a travelling crane, and then poured into the con verter, which is a fixed vessel, lined with a mixture of native fireclay and sand and pulverized English firebrick. Steam was raised to about 50 lbs. in the boilers, giving a pressure of blast of about GI or 7 lbs. per square mch, and the air was driven into the converter through 11 tuyeres of inch diameter, placed horizontally at the bottom of the vessel. No manganese or other metal was added to temper the steel, the quality of the metal re quired being regulated by the pressure of blast and the time of blowing. As soon as the metal was sufficiently decarbonized, the vessel was tapped, and the fluid steel run into a ladle provided with an outlet in the bottom. This ladle was swung round over the cast-iron ingot moulds, the fireclay plug withdrawn, and the steel allowed to flow in a clear stream into the moulds beneath. These ingots were then cogged down under a Nasmyth hammer, and drawn into finished steel bars of various sizes.