AURUM FULMINANS, (Encycl.) See Fulminating GOLD.—It has been thought that this substance, which explodes with an astonishing violence, and makes a very sharp report, would produce a far greater effect than gun-powder, if it were cheap enough to be used as a substitute for fire-arms. But repeated experiments have shown, that when fulminating gold is confined in the barrel of a pistol, in a hollow iron ball, or the like, its effects are much inferior to those of gun-powder; and the reason is, because fulminating gold produces an incomparably less quantity of elastic fluid than gun-powder does. The surprising effects produced by it when fulminating in the open air, according to Mr Cavallo, must be owing to the sudden generation of the elastic fluid, and not to the quantity of it produced. Bergman says, that the elastic fluid generated by fulminating gold is scarcely equal to four times the bulk of the fulminating gold. He also says, that half a drachm of fulminating gold, fired in a close vessel, makes a report hardly audible; and that the elastic fluid it generates, extinguishes flame, is noxious to animals, is not absorbed by water, nor renders lime-water turbid.—These are the characteristic properties of phlogisticated air.