The rolling stock of the Halfa-Sarras line was in good order and sufficient quantity, but the eight locomotives were out of all repair, and had to be patched up again and again with painful repetition.  The regularity of their break-downs prevented the regularity of the road, and the Soudan military railway gained a doubtful reputation during the Dongola expedition and in its early days.  Nor were there wanting those who employed their wits in scoffing at the undertaking and in pouring thoughtless indignation on the engineers.  Nevertheless the work went on continually.

The initial difficulties of the task were aggravated by an unexpected calamity.  On the 26th of August the violent cyclonic rain-storm of which some account has been given in the last chapter broke over the Dongola province.

A writer on the earlier phases of the war [A.  Hilliard Atteridge, towards freedom.] has forcibly explained why the consequences were so serious: 

’In a country where rain is an ordinary event the engineer lays his railway line, not in the bottom of a valley, but at a higher level on one slope or the other.  Where he passes across branching side valleys, he takes care to leave in all his embankments large culverts to carry off flood-water.  But here, in what was thought to be the rainless Soudan, the line south of Sarras followed for mile after mile the bottom of the long valley of Khor Ahrusa, and no provision had been made, or had been thought necessary, for culverts in the embankments where minor hollows were crossed.  Thus, when the flood came, it was not merely that the railway was cut through here and there by the rushing deluge.  It was covered deep in water, the ballast was swept away, and some of the banks so destroyed that in places rails and sleepers were left hanging in the air across a wide gap.’

Nearly fourteen miles of track were destroyed.  The camp of the construction gangs was wrecked and flooded.  Some of the rifles of the escort—­for the conditions of war were never absent—­were afterwards recovered from a depth of three feet of sand.  In one place, where the embankment had partly withstood the deluge, a great lake several miles square appeared.  By extraordinary exertions the damage was repaired in a week.

As soon as the line as far as Kosheh was completed, the advance towards Dongola began.  After the army had been victorious at Hafir the whole province was cleared of Dervishes, and the Egyptian forces pushed on to Merawi.  Here they were dependent on river transport.  But the Nile was falling rapidly, and the army were soon in danger of being stranded by the interruption of river traffic between the Third Cataract and Kenna.  The extension of the line from Kosheh to Kerma was therefore of vital importance.  The survey was at once undertaken, and a suitable route was chosen through the newly acquired and unmapped territory.  Of the ninety-five miles of extended track, fifty-six were through the desert,