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HARPA, a very ancient kind of instrument, in the form of a denticulated sickle, one of the symbols of Saturn who, according to a horrid myth, used it to mutilate his father, Uranus. The harpa is seen on a coin of the Neria gens, behind the head of Saturn, and on a denarius of the Sentia family, in the hands of the same deity; also on a silver coin of Valerian, accompanying the epigraph of Eternitas. (Eckhel).
Mercury is also said to have used a harpa to kill Argus, and Perseus employed it as a weapon to cut off the head of Medusa. - See SATURNUS.