science nor strength could by any possibility prevail.  Perhaps Mahmud did not realise the amazing power of movement that the railway had given his foes; perhaps he still believed, with the Khalifa, that Berber was held only by 2,000 Egyptians; or else—­and this is the most probable—­he was reckless of danger and strong in his own conceit.  At any rate, during the second week in February he began to transport himself across the Nile, with the plain design of an advance north.  With all the procrastination of an Arab he crawled leisurely forward towards the confluence of the rivers.  At El Aliab some idea of the strength of the Atbara entrenchment seems to have dawned upon him.  He paused undecided.  A council was held.  Mahmud was for a continued advance and for making a direct attack on the enemy’s position.  Osman Digna urged a more prudent course.  Many years of hard fighting against disciplined troops had taught the wily Hadendoa slaver the power of modern rifles, and much sound tactics besides.  He pressed his case with jealous enthusiasm upon the commander he detested and despised.  An insurmountable obstacle confronted them.  Yet what could not be overcome might be avoided.  The hardy Dervishes could endure privations which would destroy the soldiers of civilisation.  Barren and inhospitable as was the desert, they might move round the army at the Atbara fort and so capture Berber after all.  Once they were behind the Egyptians, these accursed ones were lost.  The railway—­that mysterious source of strength—­could be cut.  The host that drew its life along it must fight at a fearful disadvantage or perish miserably.  Besides, he reminded Mahmud —­not without reason—­that they could count on help in Berber itself.

The agreement of the Emirs, called to the council, decided the Dervish leader.  His confidence in himself was weakened, his hatred of Osman Digna increased.  Nevertheless, following the older man’s advice, he left Aliab on the 18th of March, and struck north-east into the desert towards the village and ford of Hudi on the Atbara river.  Thence by a long desert march he might reach the Nile and Berber.  But while his information of the Sirdar’s force and movements was uncertain, the British General was better served.  What Mahmud failed to derive from spies and ‘friendlies,’ his adversary obtained by gunboats and cavalry.  As soon, therefore, as Sir H. Kitchener learned that the Dervishes had left the Nile and were making a detour around his left flank, he marched up the Atbara river to Hudi.  This offered Mahmud the alternative of attacking him in a strong position or of making a still longer detour.  Having determined upon caution he chose the latter, and, deflecting his march still more to the east, reached the Atbara at Nakheila.  But from this point the distance to Berber was far too great for him to cover.  He could not carry enough water in his skins.  The wells were few, and held against him.  Further advance was impossible.  So he waited and entrenched himself, sorely troubled, but uncertain what to do.  Supplies were running short.  His magazines at Shendi had been destroyed as soon as he had left the Nile.  The Dervishes might exist, but they did not thrive, on the nuts of the dom palms.  Soldiers began to desert.  Osman Digna, although his advice had been followed, was at open enmity.  His army dwindled.