Uncanny work it was awaiting, in the silence of quietest of quiet lines, a mighty attack of which for very long there was scarce an indication. In the earlier days, save for reports from higher formations of aerodromes, hospitals, and railways far behind the German lines, the sole warning sign was in the large numbers of officers, maps in hand, observing day by day the British trenches and the country behind them. There was no great increase of movement on forward roads till about the 12th of March. Aeroplane photographs taken about this date showed that a large number of shell-holes a few hundred yards from the outpost line had been worked upon. It was surmised that these were being prepared for trench mortars, for the destruction of the British front-line system, as that of the Russians had been destroyed before the last great German advance at Riga. Significant also, in this connection, was the fact that Oskar von Hutier, who had carried out that attack, was now in line opposite, in command of Eighteenth Army. His known character and antecedents were food for reflection.
New military roads were also discovered behind Itancourt. But it was a few clear mornings and evenings, from the 15th of March onwards, that brought most conclusive evidence of what was impending. From the dovecote in Essigny, the best observation post on the XVIII. Corps front, which was manned by the 36th Division's excellent observers, an enormous amount of traffic could now be observed. Along the main road from Guise-Mont d'Origny to St. Quentin, in particular, huge convoys of lorries and horse transport were seen, as dusk drew in, moving towards the last-named city. Small place for doubt now remained.
On March the 4th occurred a curious incident. The Germans had apparently come to the conclusion that the British front line had been abandoned; and, indeed, it was held lightly enough by isolated sections. Strong patrols, amounting in general to a platoon, suddenly issued from the German trenches all along the 36th Division's front, in broad daylight. The outposts might be weak, but they could resist an attempt of this sort. Under the fire of Lewis guns all the patrols were stopped and dispersed with heavy loss. Patrols sent out in turn from the outpost companies captured in all one officer and ten other ranks. It was a sharp lesson, and thereafter, till the opening of the attack, was no move by the German infantry.
From March the 12th onward was instituted a series of nightly bombardments, in which the now considerable heavy artillery at the disposal of the XVIII. Corps took part, of valleys and dead ground forming probable assembly positions. Tests of the action to follow the preconcerted Corps message, "Man Battle Stations," were carried out. Bridges had long been prepared for demolition and allotted to particular sections of the Field Companies. Small mine-fields had been constructed in case of the employment of tanks by the enemy. Grugies Valley was starred with machine-guns, to sweep its length with zones of flanking fire. It was felt by officers and men of the Division that what the limited means at its disposal permitted had been accomplished. The worst misgivings were with regard to the gaps between keeps and redoubts in the Forward Zone, owing to the paucity of numbers available for its defence. There was no touch between the battalion headquarters forts in the Line of Redoubts; they were in no sense mutually supporting. There was little to prevent the enemy from breaking through in the intervals, pushing forward his main advance almost unembarrassed by them, while special detachments swallowed them at leisure.
Much noise of enemy traffic was heard at night from the 17th onward. On the evening of the 18th two Germans entered our lines on the front of the 107th Brigade to give themselves up. They declared they had deserted to avoid the coming battle, which would not now be long delayed. They confirmed the suspicions of massed trench mortars on the front. They had seen great numbers of troops, particularly of artillery. St. Quentin, they said, was packed with men. On the night of the 20th a raid was carried out by the 61st Division, resulting in the capture of prisoners who stated that the attack was to be launched the following morning. A special bombardment was therefore carried out from 2-30 to 3 a.m., with heavy rolling barrages on likely positions of assembly.
The great moment, for which, it is scarce exaggeration to say, men were waiting all the world over, came at 4-35 a.m. on the morning of March the 21st. The infantry of the 36th Division was then disposed as follows:
Right Brigade: 108th Brigade.
Forward Zone: 12th Rifles.
Battle Zone: 1st Irish Fusiliers.
Divisional Reserve: 9th Irish Fusiliers.
Centre Brigade: 107th Brigade.
Forward Zone: 15th Rifles.
Battle Zone: 1st Rifles.
Divisional Reserve: 2nd Rifles.
Left Brigade: 109th Brigade.
Forward Zone: 2nd Inniskillings.
Battle Zone: 1st Inniskillings.
Divisional Reserve: 9th Inniskillings.
The artillery had begun moving a large proportion of its guns to new positions on the night of the 17th, having taken a hint from the fate of batteries on the front of the Third Army, which had just been subjected to the heaviest "mustard" gas bombardments experienced in the whole course of the war. The moves of batteries of the 173rd Brigade were actually not complete till a few hours prior to the launching of the attack. The dispositions were then as follows:
Right Group. (Covering front of 108th and 107th Infantry Brigades.)[51]