pre-Hellenic cities of Asia Minor, other than Troy. The very ancient acropolis on the Yamanlar Dâgh above Smyrna possessed rectangular towers.[225] In Caria the fortification known as the Wall of the Leleges opposite Iassos had rounded towers and crémaillères,[226] and the walls of Alinda rectangular towers à cheval.[227] The Lycian towns depicted upon the bas-reliefs in the tombs at Pinara, discovered by Benndorf and Niemann, exhibit salient rectangular towers,[228] while fortified towers of the same character are depicted on the monument of the Nereids at Xanthos,[229] and we have a plan of the ancient walled town of Pydnai in which the features portrayed on the reliefs are clearly to be recognized.[230] Nor must the towns of the Phoenicians be forgotten, the towered walls of Mount Eryx in Sicily, of the acropolis of Lixos in Mauritania Tingitana, of Thapsus, of Carthage, and of Tyre.[231] With such a wide development of fortifications by means of flanking towers, extending from the cultural spheres of the Babylonians and the Hittites over all the western parts of Asia, and carried by the Phoenicians into the furthest limits of the Mediterranean, it is not surprising that the fortifications of Greek towns in the fifth century should exhibit the same features. Assos, the finest example of this period, carries on the tradition in the crémaillères and rectangular towers of its walls;[232] and Messene, with its rounded and rectangular towers, shows in the succeeding century a yet more complete understanding of military architecture.[233] The acropolis of Selinus, with semicircular towers, bears witness at a like age to the carrying over of the Greek system of defences into Sicily.[234] The walls of Ephesus, built by Lysimachus towards the close of the third century, ‘one of the greatest monuments of fortification which have been left to us by antiquity,’[235] show the towered wall of the Hellenistic age, while Mantineia, with its circular outer wall, is like an isolated reversion to the round cities of Hittite lands.[236] Philon of Byzantium formulated the laws which governed Greek fortification in the Alexandrian age. Towers, crémaillères, and casemated walls combined to make a system of defence all the elements of which had been familiar to the Hittites and to the Assyrians, and the methods of attack which he sought to counter were the same as those which can be seen on the Assyrian reliefs.[237] Vitruvius advocates the flanking of walls by round or polygonal rather than by rectangular towers, but his words should be taken as a counsel of perfection, not as representing the practice of his day, for the systematic use of rounded towers by Roman engineers is later than Augustan times and polygonal towers are unusual before the age of Diocletian. At Aosta, which was fortified soon after 25 B.C., the towers are rectangular,[238] but at Fréjus and at Autun, both of which were fortified in the Augustan age, we have two of the