The law of the emperor Theodosius, by which he prohibited his subjects, under pain of death, from teaching the art of ship-building to the barbarians, was ineffectual in the attainment of the object which he had in view; nor did any real service to the empire result from a fleet of 1100 large ships that he fitted out, to act in conjunction with the forces of the western empire for the protection of Rome against Genseric, king of the Vandals. This fleet arrived in Sicily, but performed nothing; and Genseric, notwithstanding the law of Theodosius, obtained the means and the skill of fitting out a formidable fleet. The Vandal empire in Africa was peculiarly adapted to maritime enterprise, as it stretched along the coast of the Mediterranean above ninety days' journey from Tangier to Tripoli: the woods of mount Atlas supplied an inexhaustible quantity of ship timber; the African nations whom he had subdued, especially the Carthaginians, were skilled in ship-building and in maritime affairs; and they eagerly obeyed the call of their new sovereign, when he held out to them the plunder of Rome. Thus, as Gibbon observes, after an interval of six centuries, the fleets that issued from the port of Carthage again claimed the empire of the Mediterranean. A feeble and ineffectual resistance was opposed to the Vandal sovereign, who succeeded in his grand enterprise, plundered Rome, and landed safely in Carthage with his rich spoils. The emperor Leo, alarmed at this success, fitted out a fleet of 1113 ships, at the expense, it is calculated, of nearly five millions sterling. This fleet, with an immense army on board, sailed from Constantinople to Carthage, but it effected nothing. Genseric, taking advantage of a favourable wind, manned his largest ships with his bravest and most skilful sailors; and they towed after them vessels filled with combustible materials. During the night they advanced against the imperial fleet, which was taken by surprise; confusion ensued, many of the imperial ships were destroyed, and the remainder saved themselves by flight. Genseric thus became master of the Mediterranean; and the coasts of Asia, Greece, and Italy, were exposed to his depredations.