On September 27 Harper's Fourth Corps had been given the task to capture Beauchamp Ridge and Highland Ridge, and clear the front system of the Hindenburg Line as far as the Couillet valley. The assault was launched at 5.20 in the morning. The Fifth Division on the right was from the outset sadly hampered by the fire from African Trench, which struck upon its flank and inflicted heavy losses. The division showed its usual gallantry, but the {209} position was an impossible one until the Fifth Corps got farther forward. The left of the division, however, and the Forty-second Division made good progress, though the fighting was very severe about Beauchamp, which was taken but could not be held, as a fresh German division, advancing about 7 o'clock in the evening, drove the defenders back to the west of it. The success of the Sixth Corps in the north, however, at Flesquières, had an encouraging effect upon the whole line, and about 2.30 P.M. of September 28 both the Fifth and Forty-second Divisions came on once more, the latter being particularly successful in getting prisoners and guns. The Fifth Division got Beauchamp and Highland Ridge, but was still held up on the right. By evening the line was well forward on the western slopes of Welsh Ridge, and some 1700 prisoners had come in. It was clear that the German line was sagging, so in order to press the advantage General Harper ordered up Russell's New Zealanders to carry the battle on through the night. There could be no more stringent test of the quality and discipline of troops, for the advance had to be made over unknown country covered with trenches and wire entanglements, with only a fitful, sinking moon to guide them. At 3 A.M. of a dark, cold night the splendid Colonials passed through the ranks of the Forty-second Division and, driving forward, thrust the enemy off Welsh Ridge and Bonavis Ridge beyond it, captured 1600 prisoners, and made good the line of the Canal de l'Escaut. North and South Island brigades kept line in the advance. More than thirty guns were among the trophies of this magnificent achievement. The Fifth Division on their right swept forward at the same time near La {210} Vacquerie, but as Gonnelieu upon their flank had not yet been captured by the Fifth Corps, their attack was limited on that side. This was remedied shortly after dawn, when the Fifth Division, weary as it was, cleared their own right flank, captured Gonnelieu, and finally took Banteux with 250 prisoners. The indefatigable New Zealanders had also gone forward after dawn as blithely as though it was their first attack, clearing the whole of the west bank of the Canal, and penetrating at one time into Crevecœur, where, however, they were unable to remain. They did great work here, however, by holding and partly saving the bridge, all others having been destroyed, and establishing some sort of bridgehead.