The second tank was unlucky; it set out in the darkness, and, reaching its appointed place by "zero," plunged forward after the barrage. The tank reached the first German trench. None of our infantry was in sight. The ground was so broken and the light so dim that the tank commander thought he might have overshot his mark. Perhaps the infantry were being held up behind him. He turned back to look for them, and met them advancing slowly. He swung again, but in the deceptive light the driver made a mistake, and the tank slipped sideways into a trench at an impossible angle. Most tanks can climb out of most trenches, but even a tank has its limitations. If a tank slips sideways into a certain size of trench at a certain angle, it cannot pull itself out unless it possesses certain devices which this Mark I. lacked. The tank was firmly stuck and took no part in the day's fighting.
The third tank ran into the thick of the battle, escaping by a succession of miracles the accurate fire of the German gunners. It crashed into the enemy, who were picked troops, and slaughtered them. The Germans showed no fear of it. They stood up to it, threw bombs and fired long bursts at it from their machine-guns. They had been issued with armour-piercing bullets, and the crew found to their dismay that the armour was not proof against them. Both gunners in one sponson were hit. The corporal of the tank dragged them out of the way--no easy matter in a tank--and manned the gun until he in his turn was wounded. Another gunner was wounded, and then another. With the reduced crew and the tank encumbered by the wounded, the tank was practically out of action. The tank commander broke off the fight and set out back.
While I was receiving these reports in the dug-out, Haigh had returned from brigade headquarters. The news was not good. The infantry could make little or no impression on the enemy defences. When attacking troops are reduced to bombing down a trench, the attack is as good as over, and our attack had by now degenerated into a number of bombing duels in which the picked German troops, who were holding this portion of their beloved Hindenburg Line, equalled and often excelled our men.