Bison

Subgenus, distinguished from Ox in the broader forehead, upwardly curved horns, springing in front of frontoparietal ridge of skull, shoulders higher than rump, a woolly mane and beard beneath the chin. The European Bison has one, and the American two, more pairs of ribs than the Ox, which has thirteen pairs. The American Bison is also shorter, but IMG:content-0534.jpg:[graphic] IMG:content-0535.jpg:[graphic] Bismuth. melted away from the earthy matter of its ores. The ore is put into iron tubes set at an angle and heated to ab. 300° C. The ore is stirred, and the metal runs out and collects in an outer pot. This impure metal contains lead, nickel, copper, arsenic, iron, etc., and is purified by careful liquation on a hot iron plate, or by melting in a crucible with saltpeter ltpeter and stirring with a stick of wood. Sometimes the ore itself is mixed with fluxes and run down in crucibles, adding metallic iron to neutralize any sulphur in the ore. During the cupellation of lead for silver, the bismuth present is oxidized with the last of the lead. The last parts of litharge are treated for bismuth at Freiberg by di olving in muriatic acid, diluting, collecting the precipitated oxy chloride of bismuth, and smelting it in crucibles with charcoal, silica and soda. Commercial bismuth is produced only in England, from Australian ores, and in Germany. The yearly production is ab. 50 tons, and selling price $1.50 per lb. It is sold in bars of 25 to 50 lbs., and generally averages over 99 per cent pure, the rest being copper, silver, arsenic, antimony and iron. The pure metal has a specific gravity 9.8, melting point 268° C., boils between 1,050° and 1,400° C., specific heat 0.0308, conductivity for heat 18, for electricity 12 (silver being 1,000). The color is white with a reddish-violet tint. It can be cut into a shaving by a knife, but is neither malleable nor ductile. The principal uses are for easily fusible alloys, clichés and stereotype metal. Their composition is as follows: