The siege of Constantine may properly be said to have ended the war of occupation in Africa. Hitherto we have seen the Zouaves only in time of active war, or in the defence of hill-forts, obliged to unity through fear of an ever-menacing foe, and laboring for their own preservation or comfort only; but now commenced a new training for them, no less severe and dangerous, in which they showed themselves equally willing and competent,--a war against stubborn Nature in all her most forbidding aspects. Under the blazing suns of that tropical climate they recommenced at Coleah the work already begun at Dely Ibrahim; ditches were to be dug, works thrown up, roads made, draining accomplished, farms tended, all that was necessary for the establishment of those permanent colonies which France was so anxious to settle in Algeria was to be done by the Zouaves; yet, despite that terrible labor, the danger and hardship, the sickness and death, the ranks of the regiment filled up rapidly; and, joined by the wrecks of the battalion of Mechouar, they were kept full to overflowing. This battalion of Mechouar was a troop left by Clausel in the _mechouar_, or citadel, of Tlemcen, in the West of Oran, under the command of Captain Cavaignac; on the conclusion of the war, in 1837, they, of course, returned to their regiment at Coleah. This deceitful peace lasted only till 1839. In this year the vigilant colonel of Zouaves perceived in his native troops alarming symptoms of mutiny, and learned, to his surprise, that they were in a ripe condition for revolt. Wild Santons of the desert, emissaries, doubtless, of Abd-el-Kader, held secret meetings near the camp; many soldiers attended them, and were seduced by artfully prepared inflammatory harangues and prophecies. In the month of December, 1839, at the raising of the standard of Islam, the natives flocked in vast numbers to rid the land of the Christians; and most of the native Zouaves deserted to join the fortunes of the prince whom they reverenced as a prophet. Old soldiers, trained in the French service to a thorough acquaintance with European tactics, and gray with battling long for Lamoricière, suddenly left him, and by their knowledge of the art of war gave great advantage to the Arab force. In their combats with the Sultan, the Zouaves not infrequently found that a sharp resistance or a masterly retreat on the part of the enemy was executed under the direction of one of their former comrades in arms. It was a critical moment for the Zouaves; but at the announcement of the renewal of hostilities volunteers flowed in on all sides, whether of young men full of ardor and excitement, or, as in many instances, of old soldiers who had already served their time. After a winter of petty skirmishing and reestablishing in Algeria the semblance of security, the Duke of Orléans led the army, considerably reinforced, in a raid against the Arabs under Abd-el-Kader in their own territory.