Bugeaud's main object was to establish permanent centres of action in the very heart of the Arab confederation of tribes, and, by rapidly consecutive expeditions radiating from these centres, to give his troops the ubiquity of Abd-el-Kader's forces. The chief seat of the Sultan's power was the Province of Oran, and this was made the principal scene of operations. Mascara was held by Lamoricière, Tlemsen by Bedeau. Changarnier was in observation on the western frontier of the plain of Algiers; Tittery was menaced by D'Aumale. From Oran and Mostaganem three columns were sent forth against the tribes occupying the large expanse of territory lying between the Atlas Mountains and the Mediterranean, and the tribes extending toward the Sahara. The first force, headed by Bugeaud in person, marched along the valley of the Chéliff, and then joined the second column under Changarnier, coming from Blida. The third body, under Lamoricière, aimed at pushing Abd-el-Kader back to the south in order to separate him from the tribes assailed by Changarnier and Bugeaud. The plan of campaign was formidable for the Arabs, but it was encountered by the Sultan with wonderful skill and daring in a struggle which involved some thrilling episodes, Lamoricière, in his efforts to overtake the foe, was constantly baffled. Hearing that Abd-el-Kader was before Mascara, he hurried thither by forced marches, only to find that his enemy had passed by his rear and was raiding a tribe friendly to the French. Pursuing in the new direction, the French leader was outmaneuvre by the Sultan's bold and rapid dash across the Chéliff, placing his Arabs between Bugeaud and the sea, and recovering his ascendency over the tribes in that region. Abd-el-Kader then swept in a _razzia_ to the south of Miliana, and soon appeared in full force in the Sahara as the bewildered French pursuers returned to their cantonments in despair of reaching him. This is a sample of the evolutions by which genius made amends for inferiority of force. The ablest military combinations were rendered abortive by an enemy that was ever slipping between columns, flitting in the front, hovering on the flanks, assailing the rear, and, with perfect knowledge of the country, was sometimes in the mountains and again in the plains, ubiquitous, unattainable for serious conflict.