That night Corkran’s Brigade was relieved by the Twentieth Division and returned to Carnoy. There it remained in bivouacs until the 20th, when it returned to the line just north of Ginchy. On the 18th Second Lieutenant H. C. S. Maine joined from the entrenching battalion, and on the 19th Second Lieutenant A. R. Ellice and a draft of thirty men arrived.
Going up to the trenches in front of Lesbœufs at 7 P.M. on the 20th to dig communication and assembly trenches for the attack of the 25th, the 4th Battalion had what seemed an interminable march, owing to the congestion of the traffic and the bad state of the ground. The only available road was one mass of transport, guns, etc., and so deep was the mud in some places that it was difficult to cover more than half-a-mile an hour. To make matters worse the guides who had been supplied lost their way, and it was not till three o’clock next morning that the relief was complete. The front-line trench was very shallow, and not by any means bullet-proof, while the communication trench called Gas Alley was filled with British and German corpses.
Captain Spencer-Churchill was ordered to go with his company to Gas Alley and dig a trench connecting it with the one on the right, the exact position of which was not known. He was told that the shell-holes round the block in Gas Alley were strongly held by the enemy’s snipers, and that he could call for artillery support if he thought it advisable. He decided that it would be useless to send out patrols at night, and determined to find the other trench himself. This he accomplished by going a long way round by the sunken road, and on reaching the block in the other trench he came across a small post with a Lewis gun which had attracted a good deal of attention from the Germans. Having located the other trench he returned to Gas Alley and organised a bombing party, which Lieutenant J. F. J. Joicey-Cecil was to lead.
Just as the attack was about to start next morning the Germans hurled a succession of bombs at the trench, but they exploded some distance off and no one was hurt. Then the Grenadier party broke down the block and advanced, but discovered that the Germans had retired 100 yards towards their main line, where another block had been made by filling in the trench for 40 yards. Captain Spencer-Churchill followed on and established a bombing post there. On returning to the sunken road, he received orders to take over Gas Alley and the 80 yards of the trench leading into it.