Anglo-Egyptian] 29 THE MAHDIA tants being removed to the the Dervish capital, Omdurman. The British expedition was recalled in June 1885. Sennar surrendered on July 30 , and on the same day Kassala was captured. Some of the garrisons in the eastern Sudan were rescued by the Abyssinians; King John, by the treaty of Adowa (June 3, 1884 ), receiving back Ismail's acquisitions as the price of his aid . The whole of the eastern Sudan , save Suakin, was practically abandoned. A Dervish advance to the north was checked at Ginnis on Decem ber 30 , 1885 ; but this was defensive strategy only . By April 1886 the frontier of Egypt was withdrawn to Wadi Halfa .

Meanwhile the Mahdi , who in four years had made himself undisputed ruler of two million square miles of territory, died at Omdurman on June 22 , 1885 . The Khalifa Abdulla , of the Taaisha section of Baggara , who had been his chief general , seized the power , and with some difficulty maintained his posi tion in the face of constant rebellion at home and exhausting war with the Abyssinians on the frontier.

Not until 1889 was he free to resume the plan of the invasion of Egypt. Eleven thousand Dervishes , under his Emir, Wad - el-Nejumi, were , however, defeated at Argin , a few miles beyond Wadi Halfa, on July 2 , 1889, and destroyed at Toski by Sir Francis Grenfell on August 3, in a battle which proved the sterling merit of the new Egyptian model army, for years carefully trained by and under the leadership of British officers. The Khalifa was henceforth reduced to the defensive . He lost Tokar to the Egyptian army on February 8 , 1891 , and Kassala to the Italians on July 17 , 1894 . In the far south his Emirs ' efforts to conquer the Upper Nile and Bahr el-Ghazal had never met with complete success,Emin always lurking quietly out of their reach. Darfur was always restless ; and the Nuba mountaineers remained defiant.

Yet the Khalifa, a man of great political sagacity and force of character, kept hisDervishes loyal to him, played successfully on their religious fanáticism (á [3919] D 2