(Ἄμμων), a geometrician, who made a measurement of the walls of Rome, about the time of the first invasion of the Goths, and found them to be 21 miles in circuit. (Olympiodorus, apud Phot. Cod. 80, p. 63, ed. Bekker.)
[P.S]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890