LITHOMANTIA, in Antiquity, a species of divination performed with stones. Sometimes the stone called siderites was used. This they washed in spring-water in the night by candle light; and the person who consulted it was purified from all manner of pollution, and had his face covered. This being done, he repeated divine prayers, and having placed certain characters in an appointed order, the stone then moved of itself, and in a soft, gentle murmur, or, as some say, in a voice like that of a child, returned an answer. By a stone of this nature Helenus is reported to have foretold the destruction of Troy.