Crassus replied that he would give his answer in Seleukeia, the large city on the Tigris, which was nearly pure Greek. The later Parthian capital was Ktesiphon, in the neighbourhood of Seleukeia, on the east bank of the Tigris and about twenty miles from Bagdad. The foundation of Ktesiphon is attributed by Ammianus Marcellinus (xxiii. 6, ed. Gronov.) to Bardanes, who was a contemporary of the Roman emperor Nero, if he is the Arsakes Bardanes who appears in the list of Parthian kings. But Ktesiphon is mentioned by Polybius in his fifth book, in the wars of Antiochus and Molon, and consequently it existed in the time of Crassus, though it is not mentioned in his Life. Ktesiphon is mentioned by Dion Cassius (40. c. 14) in his history of the campaign of Crassus, but this alone would not prove that Ktesiphon existed at that time.] [Footnote 61: The Greek word here and at the beginning of ch. xix., translated 'mailed' by Mr. Long, always refers to cuirassed cavalry soldiers.] [Footnote 62: C. Cassius Longinus, the friend of M. Junius Brutus, and afterwards one of the assassins of the Dictator Cæsar.] [Footnote 63: He is afterwards called Artavasdes. He was a son of the Tigranes whom Lucullus defeated, and is called Artavasdes I. by Saint-Martin. He is mentioned again in Plutarch's Life of M. Antonius. c. 39, 50.] [Footnote 64: Zeugma means the Bridge. Seleukus Nikator is said to have established a bridge of boats here, in order to connect the opposite bank with Apameia, a city which he built on the east side of the Euphrates (Plinius, _Hist. Nat._ v. 24). Zeugma afterwards was a usual place for crossing the river; but a bridge of boats could hardly be permanently kept there, and it appears that Crassus had to construct a raft. Zeugma is either upon or near the site of Bir, which is in about 37° N. Lat.]