Down the centre of the Hippodrome ran the “spina,” or division wall, which every circus showed; it was ornamented with three most curious monuments, whose strange juxtaposition seemed almost to typify the heterogeneous materials from which the new city was built up. The first and oldest was an obelisk brought from Egypt, and covered with the usual hieroglyphic inscriptions; the second was the most notable, though one of the least beautiful, of the antiquities of Constantinople: it was the three-headed brazen serpent which Pausanias and the victorious Greeks had dedicated at Delphi in 479 B.C., after they had destroyed the Persian army at Platæa. The golden tripod, which was supported by the heads of the serpents, had long been wanting: the sacrilegious Phocians had stolen it six centuries before; but the dedicatory inscriptions engraved on the coils of the pedestal survived then and survive now to delight the archæologist. The third monument on the “spina” was a square bronze column of more modern work, contrasting strangely with the venerable antiquity of its neighbours. By some freak of chance all three monuments have remained till our own day: the vast walls of the Hippodrome have crumbled away, but its central decorations still stand erect in the midst of an open space which the Turks call the Atmeidan, or place of horses, in dim memory of its ancient use. Along the outer eastern wall of the Hippodrome on the western edge of the Augustaeum, stood a range of small chapels and statues, the most important landmark among them being the _Milion_ or central milestone of the empire, which we have already described. The statues, few at first, were increased by later emperors, till they extended along the whole length of the forum. Constantine’s own contribution to the collection was a tall porphyry column surmounted by a bronze image which had once been the tutelary Apollo of the city of Hierapolis, but was turned into a representation of the emperor by the easy method of knocking off its head and substituting the imperial features. It was exactly the reverse of a change which can be seen at Rome, where the popes have removed the head of the Emperor Aurelius, and turned him into St. Peter, on the column in the Corso. [Illustration] Building A Palace (from a Byzantine MS.)