Note 11: — II.—COINS. (Table-Case K.)

A typical series of the Roman heavy bronze money is exhibited (No. 38; fig. 14) The system is based on the pound of twelve ounces, and the denominations of the various pieces are distinguished by the heads or obverse types, and by the marks of value which they bear. The series consists of the As, or pound (I), the half, Semis (S), the third, Triens, of four ounces (····), the quarter, Quadrans, of three ounces (···), the sixth, Sextans, of two ounces (··), and the Uncia, or ounce, the lower unit (·) (cf. p. 160). Each of these is further differentiated by the obverse head. The as has the double head of Janus, the god of beginnings, whose coin opened the series of money, as his month begins the year. The semis has the head of Jupiter, wearing a laurel wreath; the triens, Minerva armed; the quadrans, Hercules in the lion-skin; the sextans, Mercury, the messenger, with wings in his cap; and the uncia, a head of Bellona, the goddess of battle. All the reverses have a common type, the prow of a ship. This device may mark the date of the introduction of the Roman coinage, which coincided with Rome's first essays on the sea, in the middle of the fourth century before Christ. It remained as the reverse type of the bronze money all through the Republic, and even in later times, when a coin was tossed, the cry was "heads" or "ships."11