Signallers were responsible for sending messages. In previous wars signallers communicated information by flags, lamps and heliographs. None of these methods could be used in trench warfare. Instead they used morse code and field telephones.
In the early part of the war, signallers began laying cables along the floor of trenches. When they discovered that the cables were constantly being broken by soldiers' boots, they attached the lines to the trench walls with staples. This was an improvement but they were still vulnerable to enemy shell-fire. It was therefore decided to bury the cables under the ground. Even when sheathed in steel and placed 3 ft. below the surface, cables could still be broken by a shell landing in the trench.
Signallers were trained to encode and decode messages. They also had the responsibility of repairing any damaged cable. As this usually happened during heavy bombardment, the casualty-rate amongst signallers was fairly high.
On 10th August 1916, Second Lieutenant A.A. Milne and four other men were sent out to run out telephone cable so that during forthcoming attack communications with battalion and brigade headquarters could be maintained. During the operation, the senior Signalling Officer, Kenneth Harrison, suffered a serious head wound from a shell splinter. Milne now took over from Harrison and the following night he laid another telephone line. As he later recalled: "elaborately laddered according to the text books, and guaranteed to withstand any bombardment".
The Commanding Officer of the Royal Warwickshire Regiment, Lieutenant Colonel Charles Collison, admitted that the results of the preliminary bombardment: "Not only would it render the trench uninhabitable to our men, should they succeed in taking it, but it was plain intimation to the Hun that we contemplated some action against him in the near future."
On 12th August 1916, Milne's infantry platoon left the front-line trenches. The men made their attack behind a barrage that lifted as they went forward. Immediately they came under intense German machine gun fire. None of Milne's men got to within twenty yards (18.2m) of the German trench. The battalion lost around sixty killed, and just over a hundred wounded. Of the five officers who led the attack, three were killed and two severely wounded.
Lieutenant Colonel Charles Collison wrote a report that claimed his men had died bravely: "I may mention that I saw no man lying otherwise than with his face to the enemy." A.A. Milne interpreted these events differently and later claimed that this attack changed his view of the war: "It makes me almost physically sick of that nightmare of mental and moral degradation."
We passed one of the signal stations, no longer a station but a pancake of earth on top of a spread-eagled body; I had left him there that evening, saying, "Well, you'll be comfortable here." More rushes, more breathers, more bodies, we were in the front line. The Major hurried off to collect what men he could, while I joined up the telephone. Hopeless, of course, but we could have done no more.