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, and the constructors here gained the experience which was afterwards of value on the great Desert Railway from Wady Halfa to the Atbara. Battalions of troops were distributed along the line and ordered to begin to make the embankments. Track-laying commenced south of Kosheh on the 9th of October, and the whole work was carried forward with feverish energy. As it progressed, and before it was completed, the reach of the river from the Third Cataract to Kenna ceased to be navigable. The army were now dependent for their existence on the partly finished railway, from the head of which supplies were conveyed by an elaborate system of camel transport. Every week the line grew, Railhead moved forward, and the strain upon the pack animals diminished. But the problem of feeding the field army without interfering with the railway construction was one of extraordinary intricacy and difficulty. The carrying capacity of the line was strictly limited. The worn-out engines frequently broke down. On many occasions only three were in working order, and the other five undergoing 'heavy repairs' which might secure them another short span of usefulness. Three times the construction had to be suspended to allow the army to be revictualled. Every difficulty was, however, overcome. By the beginning of May the line to Kenna was finished, and the whole of the Railway Battalion, its subalterns and its director, turned their attention to a greater enterprise.
In the first week in December the Sirdar returned from England with instructions or permission to continue the advance towards Khartoum, and the momentous question of the route to be followed arose. It may at first seem that the plain course was to continue to work along the Nile, connecting its navigable reaches by sections of railway. But from Merawi to Abu Hamed the river is broken by continual cataracts, and the broken ground of both banks made a railway nearly an impossibility. The movements of the French expeditions towards the Upper Nile counselled speed. The poverty of Egypt compelled economy. The Nile route, though sure, would be slow and very expensive. A short cut must be found. Three daring and ambitious schemes presented themselves: (1) the line followed by the Desert Column in 1884 from Korti to Metemma; (2) the celebrated, if not notorious, route from Suakin to Berber; (3) across the Nubian desert from Korosko or Wady Halfa to Abu Hamed.
The question involved the whole strategy of the war. No more important decision was ever taken by Sir Herbert Kitchener, whether in office or in action. The request for a British division, the attack On Mahmud's zeriba, the great left wheel towards Omdurman during that battle, the treatment of the Marchand expedition, were matters of lesser resolve than the selection of the line of advance. The known strength of the Khalifa made it evident that a powerful force would be required for the destruction of his army and the capture of his capital. The use of railway transport to some point on the Nile whence there was a clear waterway was therefore imperative. Berber and Metemma were known, and Abu Hamed was believed, to fulfil this condition. But both Berber and Metemma were important strategic points. It was improbable that the Dervishes would abandon these keys to Khartoum and the Soudan without severe resistance. It seemed likely, indeed, that the Khalifa would strongly reinforce both towns, and desperately contest their possession. The deserts between Korti and Metemma, and between Suakin and Berber, contained scattered wells, and small raiding parties might have cut the railway and perhaps have starved the army at its head. It was therefore too dangerous to project the railway towards either Berber or Metemma until they were actually in our hands. The argument is circular. The towns could not be taken without a strong force; so strong a force could not advance until the railway was made; and the railway could not be made till the towns were taken.
Both the Korti-Metemma and the Suakin-Berber routes were therefore rejected. The resolution to exclude the latter was further strengthened by the fact that the labour of building a railway over the hills behind Suakin would have been very great.
The route via Abu Hamed was selected by the exclusion of the alternatives. But it had distinct and apparent advantages. Abu Hamed was within striking distance of the army at Merawi. It was not a point essential to the Dervish defences, and not, therefore, likely to be so strongly garrisoned as Berber or Metemma. It might, therefore, be captured by a column marching along the river, and sufficiently small to be equipped with only camel transport. The deserts through which the railway to Abu Hamed would pass contain few wells, and therefore it would be difficult for small raiding parties to cut the line or attack the construction gangs; and before the line got within reach of the Dervish garrison at Abu Hamed, that garrison would be dislodged and the place seized.
The plan was perfect, and the argument in its favour conclusive. It turned, however, on one point: Was the Desert Railway a possibility? With this question the General was now confronted. He appealed to expert opinion. Eminent railway engineers in England were consulted. They replied with unanimity that, having due regard to the circumstances, and remembering the conditions of war under which the work must be executed, it was impossible to construct such a line. Distinguished soldiers were approached on the subject. They replied that the scheme was not only impossible, but absurd. Many other persons who were not consulted volunteered the opinion that the whole idea was that of a lunatic, and predicted ruin and disaster to the expedition. Having received this advice, and reflected on it duly, the Sirdar ordered the railway to be constructed without more delay.
A further question immediately arose: Should the railway to Abu Hamed start from Korosko or from Wady Halfa? There were arguments on both sides. The adoption of the Korosko line would reduce the river stage from Assuan by forty-eight hours up stream. The old caravan route, by which General Gordon had travelled to Khartoum on his last journey, had been from Korosko via Murat Wells to Abu Hamed. On the other hand, many workshops and appliances for construction were already existing at Wady Halfa. It was the northern terminus of the Dongola railway. This was an enormous advantage. Both routes were reconnoitred: that from Wady Halfa was selected. The decision having been taken, the enterprise was at once begun.
Lieutenant Girouard, to whom everything was entrusted, was told to make the necessary estimates. Sitting in his hut at Wady Halfa, he drew up a comprehensive list. Nothing was forgotten. Every want was provided for; every difficulty was foreseen; every requisite was noted. The questions to be decided were numerous and involved. How much carrying capacity was required? How much rolling stock? How many engines? What spare parts? How much oil? How many lathes? How many cutters? How many punching and shearing machines? What arrangements of signals would be necessary? How many lamps? How many points? How many trolleys? What amount of coal should be ordered? How much water would be wanted? How should it be carried? To what extent would its carriage affect the hauling power and influence all previous calculations? How much railway plant was needed? How many miles of rail? How many thousand sleepers? Where could they be procured at such short notice? How many fishplates were necessary? What tools would be required? What appliances? What machinery? How much skilled labour was wanted? How much of the class of labour available? How were the workmen to be fed and watered? How much food would they want? How many trains a day must be run to feed them and their escort? How many must be run to carry plant? How did these requirements affect the estimate for rolling stock? The answers to all these questions, and to many others with which I will not inflict the reader, were set forth by Lieutenant Girouard in a ponderous volume several inches thick; and such was the comprehensive accuracy of the estimate that the working parties were never delayed by the want even of a piece of brass wire.
In any circumstances the task would have been enormous. It was, however, complicated by five important considerations: It had to be executed with military precautions. There was apparently no water along the line. The feeding of 2,000 platelayers in a barren desert was a problem in itself. The work had to be completed before the winter. And, finally, the money voted was not to be outrun. The Sirdar attended to the last condition.