in natural history, a name given to an imaginary stone, the effects of which upon gold were similar to those of the loadstone upon iron. The ancients, as well as some modern writers, seem to have had an opinion that there was such a stone; and the amphibane of Pliny is described as possessing this remarkable quality; but neither they nor we have ever found reason, from any experiment well ascertained, to believe that there ever was such a stone.