A case is cited of a workman in Hamburg engaged in pulverising pure antimony who was attacked with vomiting which lasted for several days, and the inspector of factories noted epistaxis (nose bleeding) and vomiting as following on the crushing of antimony ore. Compositors in addition to chronic lead poisoning may suffer, it is alleged, from chronic antimony poisoning, showing itself in diminution in the number of white blood corpuscles and marked eosinophilia. These changes in the blood could be brought about experimentally in rabbits. Antimony was found by the Marsh test in the stools of those affected. IRON _Pig iron_ is obtained by smelting iron ores in blast furnaces (fig. 29), through the upper opening of which charges of ore, limestone or similar material to act as a flux, and coke are fed in succession. The furnaces are worked continuously, using a blast of heated air; carbon monoxide is produced and effects the reduction of the ore to molten iron. The latter accumulates in the hearth and is covered with molten slag; this flows constantly away through an opening and is collected in slag bogies for removal, or is sometimes cooled in water. The crude iron is tapped from time to time, and is led in a fluid condition into moulds called ‘pigs,’ in which it solidifies. Cast iron is occasionally used direct from the blast furnace for the purpose of making rough castings, but generally it is further refined before being used in a foundry by remelting with cast iron scrap in a cupola furnace. [Illustration: FIG. 29. _a_ Hearth; _b_ Bosh; _c_ Shaft; _d_ Gas uptake; _e_ Down-comer; _f_ Tuyères with water cooling arrangement; _g_ Blast pipes; _h_ Tapping hole; _k_ Supporting columns; _l_ Furnace bottom; _m_ Charging hopper; _n_ Bell with raising and lowering arrangement.] _Wrought iron_ is made by treating pig iron in refinery and puddling furnaces; in these much of the carbon is removed as carbon monoxide, and from the puddling furnace the iron is obtained as a pasty mass which can be worked into bars, rods, or plates. _Steel_ is made in various ways. The Acid Bessemer process consists in forcing compressed air in numerous small streams through molten cast iron, in iron vessels (converters) which are lined with ganister, a silicious sandstone. These can be rotated on trunnions. Basic Bessemer steel is made in similar converters by the Thomas-Gilchrist or basic process, which can be applied to pig irons containing phosphorus. The latter is removed by giving the converter a basic lining of calcined magnesium limestone mixed with tar. In the _Martin_ process steel is obtained by melting together pig iron with steel scrap, wrought iron scrap, &c., on the hearth of a Siemens regenerative furnace with a silicious lining. In iron smelting the most important danger is from _blast furnace gas_ rich in carbonic oxide. Sulphur dioxide, hydrocyanic acid, and arseniuretted hydrogen gas may possibly be present.