AMPSANCTUS or AMSANCTUS (mod. Sorgente Me fita), a small lake in the territory of the Hirpini, Iom. S.E. of Aeclanum, close to the Via Appia. There are now two small pools which exhale carbonic acid gas and sulphuretted hydrogen. A temple of the goddess Mephitis had a cave with suffocating va pours and the place was brought into connection with legends of the infernal regions.