skilfully built and cemented that they presented the appearance of one vast continuous block of stone. Visitors to the city in after days hardly knew whether to wonder most at the art and finish displayed in their origin and construction, or at the destructive power of the besieging army of Severus. The Byzantines, too, were well furnished with every appliance which science could contrive for the purposes of defence. They had engines, it is said, which could lift ships out of the water; and, what was far better, they had an engineer officer of the first capacity to organise the defence. The man's name was Priscus, and so much did he impress Severus by his singular skill and tenacity, that the emperor subsequently took him into his service and availed himself of his talents. The city had also a numerous and well-appointed fleet. Three hundred vessels of every variety, well piloted and manned, some armed with particularly formidable beaks, were at the disposal of the Byzantines.
For the unusually long period of three years they defended themselves; and their brave persistency amid the sufferings which so prolonged a struggle necessarily involved, shows plainly enough that in great emergencies these citizens, who had the character of being mere lovers of ease and comfort, could rise to a high degree of patriotism and loyalty. Severus, it seems, though he did not personally conduct the siege, had staked everything on success, and be the cost what it might, he must capture Byzantium to secure his power in the East. He had one decided advantage. Already by his victories over Niger he had made himself completely master of
