Tungsten

a metallic element. It is known also as wolfram. Symbol, W; specific gravity, 16.6. It is a heavy metal, harder than glass and more magnetic than iron. It was long mistaken for tin. It is worth about $1.25 a pound. Pure tungsten is hard enough to scratch glass. Tungsten fuses at a higher temperature than any other metal known. Tungsten metal is used for the filament of electric light bulbs. It is considered superior to the old bamboo and the newer carbon filament. It is claimed that, with a tungsten filament, only one-third as great an electric current is needed. As the metal cannot be drawn into wire, the filaments are formed by forcing tungsten "dough" through an "eye." An alloy of tungsten is used for tool steel. It resists rust. Five per cent of tungsten is used in making magnets. Tungsten for strength is added to steel used in heavy guns and battleship armor. Aluminum with a percentage of tungsten combines lightness and strength, a union of qualities much sought by makers of automobiles. Ores from which tungsten may be extracted are found in Montana, Canada, Australia, New Zealand, Great Britain, Saxony, Bohemia, and Spain, but a less expensive source of supply is to be desired.