The characteristic weapon, however, was the _pilum_ (Gr. [Greek: ussos]). The form of this weapon and the mode of using it have been minutely described by Polybius (vi. 23), but his description has been much misunderstood in consequence of the rarity of representations or remains of the _pilum_. It is shown on a monument of St Remy in Provence, assigned to the age of the first emperors, and in a bas-relief at Mainz, on the grave-stone of Quintus Petilius Secundus, a soldier of the 15th legion. A specimen of the actual weapon is in the museum at Wiesbaden. It is a javelin with a stout iron head (7 in.), carried on an iron rod, about 20 in. in length, which terminates in a tang for insertion in the wooden shaft. As represented on the monuments, the iron part of the weapon is about one-third of its entire length (6-3/4 ft.). It was used primarily as a missile. When the point pierced the shield the weight of the stave pulled the shield downwards and rendered it useless. At close quarters it answered all the purposes, offensive and defensive, of the modern bayonet when "fixed." Vegetius, in his _Rei militaris instituta_, describes it in a modified form as used in the armies of the lower empire, and in a still more modified form it reappears as the "argon" of the Franks. This equipment was characteristic of _hastati, principes_ and _triarii_ (save that the latter used the _hasta_ instead of the _pilum_). We thus see how great is the change from the time when the _hastati_ were the light-armed (from _hasta_) of the Greek phalanx. The cavalry, which had originally been protected only by a light ox-hide shield and the most fragile spears, adopted, about Polybius's time, the full Greek equipment of buckler, strong spear and breastplate. In the last period of the republic the _pilum_ became the universal weapon of the heavy-armed, while the auxiliaries (all foreigners, the _velites_ having disappeared) used the _hasta_ and the long single-edged sword (_spatha_). Under the empire the heavy-armed, according to Josephus, had helmet, cuirass, a long sword worn on the left side, and a dagger on the right, _pilum_ and _scutum_. The special detachment detailed to attend the commander had a round shield (_clipeus_) and a long spear. The cavalry wore armour like that of the infantry, with a broadsword, a buckler slung from the horse's side, a long pole for thrusting, and several javelins, almost as large as spears, in a sheath or quiver. Arrian, writing of a period some fifty years later, gives further particulars from which we gather that of the cavalry some were bowmen, some polemen, while others wielded lances and axes. For the arms and armour of other peoples of antiquity see e.g. PERSIA: _History, Ancient_, section v. "The Persian Empire of the Achaemenids"; BRITAIN, _Anglo-Saxon_, section v. "Warfare"; ETRURIA; EGYPT, &c. (J. M. M.)