Retreat and pursuit now attained their maximum speed, the greatest pressure being always on the west. The city and important railway centre of Amiens was evacuated by d’Amade, and occupied by Kluck’s extreme right, on August 30 (the British base had already been moved to St. Nazaire). On that memorable Sunday, all the roads converging towards Paris were crowded with fugitives, whose panic-haste was only too well justified by the barbarities that marked the progress of the invasion. On the 31st, while the 5th Army was still north of Laon, Kluck was driving across the rearguards of Maunoury and of the British (restored to the general line, after a day’s rest) in the Clermont–Compiègne region. The curvature of the Allied line, and the threat of envelopment on the left, or division of the left from the centre, were acute. As we shall see, however, the enemy had fallen into a more perilous predicament. Paris had begun to be a major factor in the situation. The railways running southward from the capital were overwhelmed with multitudes of flying civilians; so that the detrainment of some of the reinforcements from the east had to be made at a point more distant than had been intended.[40] The British Commander-in-Chief, conscious of the weakness of his means, but sensible also of what might happen to the great city, now expressed his readiness to take part in a general battle before Paris, provided that his flanks could be covered.[41] But neither of Joffre’s two new armies, the 6th and 9th, was ready for a decisive test. Kluck was hard upon the heels of d’Amade, Maunoury, and the British; and even on the Marne they might not be able to make a stand. Weighing up the possibilities from hour to hour, the Generalissimo concluded that he was not yet justified in risking everything. On September 1, from his headquarters, which were moved on that day from Vitry to a quiet château at Bar-sur-Aube, orders were issued to extend the retreat by another 30 miles to the south banks of the Aube and the Seine. “Despite the tactical successes obtained by the 3rd, 4th, and 5th Armies on the Meuse and at Guise,” he wrote, “the enveloping movement of the left of the 5th Army, insufficiently arrested by the British troops and the 6th Army, obliges the whole of our formation to pivot upon its right. As soon as the 5th Army has escaped the enveloping manœuvre against its left, the mass of the 3rd, 4th, and 5th Armies will resume the offensive.” This order marks the moment at which Verdun became a pivot for the remaining portion of the western retreat. “We shall reach this line,” the Generalissimo added (September 2), “only if we are constrained. We shall attack, before reaching it, if we can realise a disposition permitting the co-operation of the whole of the forces.”