On September 15th the German command had another shock when the whole line of the British troops on the Somme front south of the Ancre rose out of their trenches and swept over the German defenses in a tide.

Those defenses broke hopelessly, and the waves dashed through. Here and there, as on the German left at Morval and Lesbœufs, the bulwarks stood for a time, but the British pressed against them and round them. On the German right, below the little river of the Ancre, Courcelette fell, and Martinpuich, and at last, as I have written, High Wood, which the Germans desired to hold at all costs, and had held against incessant attacks by great concentration of artillery, was captured and left behind by the London men. A new engine of war had come as a demoralizing influence among German troops, spreading terror among them on the first day out of the tanks. For the first time the Germans were outwitted in inventions of destruction; they who had been foremost in all engines of death. It was the moment of real panic in the German lines⁠—a panic reaching back from the troops to the High Command.