Belisarius had reached the posting-station of Ad Decimum, and was advancing cautiously with strong corps of observation securing his flank and front, when suddenly he was assailed by the whole force of the Vandals, who outnumbered him in at least the proportion of two to one. He was beset on three sides at once; one corps of Vandals under the king’s brother Ammatas issued from Carthage to attack him in front; another body beset his left flank; the main army under Geilamir himself assailed the rear of his long column of march. But the Vandals mismanaged their tactics, and failed to combine the three attacks. First the troops from Carthage came out, and were beaten off with the loss of their leader; then the turning corps was driven back by the Hunnish cavalry, whom Belisarius had kept lying out on his flank. When the main Vandal army came up there was more serious fighting with the centre and rear of the Roman column. Geilamir furiously burst through the line of march, and cleft the Roman army in twain, but he did not know how to use his advantage. Instead of improving his first success, he halted his troops, and allowed Belisarius to rally and re-form his men. It is said that he was so transported with grief at finding the corpse of his brother, who had fallen in the earlier engagement, that he gave no more orders, and cast himself weeping on the ground. Presently, the Romans were in good array again; their victorious vanguard had returned to aid the centre, and they fell once more, as the evening closed in, on the stationary masses of the Vandals. The conquerors of Africa must have forgotten their ancient valour, for, after a very paltry resistance, they turned and fled westward under cover of the night. Carthage at once threw open its gates, and Belisarius dined next day in the royal palace on the meal that had been prepared for the Vandal king. [Sidenote: Carthage taken.] Geilamir reaped now the reward for the hundred years of persecution to which his forefathers had subjected the Africans. Every town that was not garrisoned opened its gates to the Romans, and the provincials hastened to place everything they possessed at the disposal of Belisarius. His entry into Carthage was like the triumph of a home-coming king, and the order and discipline of his troops was so great that none even of the Vandal and Arian citizens suffered loss. Geilamir meanwhile retired into the Numidian hills, with an army that had suffered more loss of _morale_ than loss of numbers. He was soon joined by the troops whom he had sent to Sardinia; having subdued that island they returned, and raised his forces to nearly 50,000 men. Finding that Belisarius was repairing the walls of Carthage before marching out to finish the campaign, Geilamir resolved to take the offensive himself. Descending from the hills he marched on Carthage, and met the Roman army at Tricameron, twenty miles westward of the city.