That night a terrible artillery fire swept the wood "as a tropical storm sweeps the leaves from a forest," and the Canadians fell back from the position which they had won at the price of many a brave life. All through the night the fighting went on without pause. The attacks constantly grew in strength, and it seemed hardly possible that the Canadians could resist much longer. At six on the morning of Friday the enemy began an outflanking movement that looked very dangerous. In order to relieve the strain a counter-attack on the first line of German trenches was ordered. This was carried out by the Ontario 1st and 4th Battalions of the 1st Brigade, under General Mercer. The advance was made across 2,300 yards of open country, every yard of which was under hot shell fire. "It is safe to say," writes Sir Max Aitken, the Canadian record officer, "that the youngest private in the ranks, as he set his teeth for the advance, knew the task in front of him, and the youngest subaltern knew all that rested on its success. It did not seem that any human being could live in the shower of shot and shell which began to play upon the advancing troops. "They suffered terrible casualties. For a short time every other man seemed to fall, but the attack was pressed ever closer and closer. The 4th Canadian Battalion at one time came under a particularly withering fire. For a moment--not more--it wavered. Its most gallant commanding officer, Lieutenant-Colonel Birchall, carrying, after an old fashion, a light cane, coolly and cheerfully rallied his men, and at the very moment when his example had infected them, fell dead at the head of his battalion. With a hoarse cry of anger they sprang forward (for, indeed, they loved him) as if to avenge his death. "The astonishing attack which followed, pushed home in the face of direct frontal fire, made in broad daylight, by battalions whose names should live for ever in the memories of soldiers, was carried to the first line of the German trenches. After a hand-to-hand struggle, the last German who resisted was bayoneted, and the trench was won." The Canadian left was now safe. The German trench was occupied, and held against all comers in the teeth of every kind of deadly missile that could be hurled against it. It was still in the hands of the victors on Sunday, 25th April, when all that remained of the war-broken battalions was relieved.