In the year 647, the covetous glances of the government at Medina were turned towards the rich plantations and populous settlements of Al-Maghreb; and the predatory inroads which had hitherto vexed its borders were, for the first time, superseded by a systematic and determined attempt at conquest. The weakness and partiality of Othman, with whom the aggrandizement of his family was a paramount consideration, had removed the famous Amru from the viceroyalty of Egypt, and invested with its administration Abdallah-Ibn-Sa’d, the foster-brother of the Khalif, a warrior of experience and courage and the finest horseman of his nation, but a man whose renown had been sullied by the crime of apostasy, and who had used an employment of confidence to ridicule and revile the inspired teachings and sacred character of the Prophet. Calling into requisition all the resources of his government, this Moslem general marched into the Desert with twenty thousand soldiers, among them many of the companions of Mohammed and representatives of the most noble tribes of Arabia. After a few unimportant skirmishes, and a short but bloody engagement in which a division of the Greeks was entirely destroyed, the Arab army advanced to Tripoli, and, investing its walls, pushed forward the operations of the siege with an energy hardly to be expected from a people whose experience had been confined to marauding expeditions and the stratagems of partisan warfare. Under the dominion of the Byzantine emperors, the office of prefect had been substituted for that of the ancient proconsul; and this employment was not only charged with the execution of the laws relating to civil and military affairs, but also claimed jurisdiction over matters pertaining to the welfare of the church, the appointment of its ministers, and the enforcement of the canons of ecclesiastical discipline. The prefect Gregory, whose talents had been exercised, and whose prowess had been approved, in many negotiations and conflicts with the Berbers, at the head of a tumultuous and undisciplined force of one hundred and twenty thousand men, moved forward to the relief of Tripoli. Abandoning the siege, the Arabs accepted the challenge, and a series of battles ensued without decided advantage upon either side, until the prefect, mortified that the numerical superiority of his troops should be neutralized by the desperate courage of his adversaries, offered the hand of his beautiful daughter--who, completely armed, was each day conspicuous in the ranks of the vanguard--and a purse of one hundred thousand pieces of gold to any one who would bring him the head of the Moslem general. The courage of Abdallah, although he had faced death in a hundred forms, was not proof against this effort of his wily antagonist, and, remaining idly in his tent, he left the conduct of operations to the care of his lieutenants. In the mean time there arrived at the Arab camp a small detachment headed by Ibn-al-Zobeir, a