The evacuation of the town, during the next two days, was a nightmare of flying masonry, clouds of dust, the roar of falling brick-work, contradictory orders, and mobs of drifting civilians, their belongings pushed before or hauled after them; and no power to order them where to go. Arras, always in the front line, had been safe so long, it was inconceivable that there should be real danger now. Might they not camp out and return to-morrow? But the enemy were reported almost in sight, and ready to open on the town with their field-guns. They had broken through, men said, under cover of the heavy morning fog--broken through everywhere along the line of all our old gains from Lens to St. Quentin, and their whole strength was behind the blow. No one could understand it, though all men argued; and while the refugees fled forth, expostulating, blaming, but seldom weeping, that sunny day, eight hundred shells fell purposefully on the dishevelled town. By evening word came that our Somme line had not only broken but gone out--infantry, artillery and uncounted stores--between Chérisy and Demicourt in the north. South of that, the old Cambrai Salient, which had not been hardly tried, was standing but would have to withdraw or be cut off, because, from Gouzeaucourt to La Fère, ten miles and more south of St. Quentin, the German tide had swept in from one to three miles deep, and was racing forward. It is not difficult to imagine what manner of reports the mere truth gave birth to, while the Battalion waited on in the Communal College where it was billeted, and was not encouraged to wander about the rocking, sliding streets. By the evening of the 22nd March men began to understand it was no mere break-through but a collapse such as had never befallen British arms in the history of her people. Officers were sent out in the morning to reconnoitre the support-line of a third system of defence between Wancourt and Hénin-sur-Cojeul. But Hénin-sur-Cojeul was already under the hand of the enemy, who had gained three more miles in a few hours and, left and right, were widening the breach.