The accomplishment of such a task, the maintenance of the "operative corner" in being during its ordeal of retreat before vastly superior numbers, and in particular the exceedingly perilous retirement of the British contingent at what was, during the first part of the strain, the extreme of the line, are what we are now about to follow. The initial counter-attack, then, on this Monday, the first day of the retreat, was undertaken by the 2nd British Division from the region of Harmignies, which advanced as though with the object of retaking Binche. The demonstration was supported by all the artillery of the 1st Army Corps, while the 1st Division, lying near Peissant, supported this action of the 2nd. While that demonstration was in full activity, the 2nd Corps to the west or left (not all of it was yet in the field) retired on to the line Dour-Frameries, passing through Quaregnon. It suffered some loss in this operation from the masses of the enemy, which were pressing forward from Mons. When the 2nd Corps had thus halted on the line Dour-Frameries, the 1st Corps, which had been making the demonstration, took the opportunity to retire in its turn, and fell back before the evening to a line stretching from Bavai to Maubeuge. [Illustration: Sketch 50.] The 2nd Corps had entrenched itself, while the 1st Corps was thus falling back upon its right; and when it came to the turn of the 2nd Corps to play the part of rearguard in these alternate movements, the effort proved to be one of grave peril. [Illustration: Sketch 51.] Since the whole movement of the enemy was an outflanking movement, the pressure upon this left and extreme end of the line was particularly severe. The German advance in such highly superior numbers overlapped the two British corps to _their_ left or west, which was at this moment the extreme end of the Allied Franco-British line. They overlapped them as these pursuing Black units overlap the lesser retiring White units. It is evident that in such a case the last unit in the line at A will be suffering the chief burden of the attack. An attempt was made to relieve that burden by sending the and Cavalry Brigade in this direction to ride round the enemy's outlying body; but the move failed, with considerable loss to the 9th Lancers and the 18th Hussars, which came upon wire entanglements five hundred yards from the enemy's position. There did arrive in aid of the imperilled end of the line reinforcement in the shape of a new body. One infantry brigade, the 19th, which had hitherto been upon the line of communications, reached the army on this its central left near Quarouble and a little behind that village before the morning was spent. It was in line before evening. This reinforcement lent some strength to the sorely tried 2nd Corps, but it had against it still double its own strength in front, and half as much again upon its exposed left or western flank, and it suffered heavily.