ACHELOUS, a river of Acarnania, which rises in Mount Pindus, and dividing Ætolia from Acarnania, falls into the Ionian Sea. It was formerly called Thoas, from its impetuosity, and king of rivers. (Homer.) The epithet Acheleus is used for Aquens (Virgil), the ancients calling all water Achelous, especially in oaths, vows, and sacrifices, according to Ephorus: now called Aspro Potamo. Rivers are by the ancient poets called Tauriformes, either from the bellowing of their waters, or from their ploughing the earth in their course. Hercules, restraining by dykes and mounds the inundations of the Achelous, is said to have broken off one of his horns, and to have brought back plenty to the country. See the preceding article.