Acheron, the name given to several rivers by the ancients, always with reference to some peculiarity, such as black or bitter waters, or meplitic gases. The Acheron, in Thesprotia in Epirus, flowing through the lake Acherusia into the Ionian Sea; another river of the same name in Elis, now called Sacuto; and several streams in Egypt—were all supposed to have some communication with the infernal world. According to Pausanias, Homer borrowed from the river in Thesprotia the name of his infernal Acheron, which the later poets surrounded with many imaginary horrors. Other lakes or swamps of the same name occur near Hermione in Argolis, between Cumæ and Cape Misenum in Campania, and in Egypt, near Memphis.
À-cheval Position. When troops are arranged so that a river or highway passes through the centre and forms a perpendicular to the front, they are said to be drawn up in à-cheval position.