The general situation in May was still such as to cause our High Command a certain anxiety. It is easy to be wise after the event and say that the Germans must obviously have outrun their transport and overtaxed the limited road capacity of the devastated area which lay behind them. In early May this, though true, was not obvious. Meanwhile, we had been too much weakened by the disasters of the last six weeks to be able to counter-attack. Consequently, the enemy had the same opportunities for reconstruction as we had ourselves, and although we felt confident that after such a hurricane of battles there must be a breathing space for both Armies, we were by no means certain what would be the respective rôles of the two opposing sides when the struggle came to be resumed. Our most pressing need was the filling of the gaps in our Divisions and the closing of the huge breaches which the German advance had made in our defensive systems. The greatest need was for men. We had, it is true, to lay out new trench lines and reconstruct such old systems as already existed, but it was not likely that the enemy would afford us time to establish new defences comparable with those which he had already proved his power of overrunning. Therefore it was to procuring new and well-trained troops that our chief efforts must be directed. The men procured, there must be railways upon which to move them. [62]“The depth to which the enemy had penetrated in the Somme and Lys valleys had disrupted important lateral lines of railway, and had created a situation of extreme gravity with regard to the maintenance of communications in Northern France. At Amiens, Béthune, and Hazebrouck, much-used railway junctions had been brought under the effective fire of the enemy’s guns, while the railway centre at St. Pol was threatened. To relieve the situation a comprehensive programme of railway construction was undertaken.”