In the case of Harper's Fourth Corps on the left the advance on August 21 was limited, since no serious attack could be made upon Miraumont while the high ground to the south was untaken. At this date Harper's Corps consisted of five divisions, the Fifth, Thirty-seventh, Forty-second, Sixty-third, and the New Zealanders. Of these the Thirty-seventh Division (Williams) was on the left, covering the flank of the Sixth Corps, while the Forty-second (Solly-Flood) was on the right. We shall now follow in the first instance the work of the Fifth Corps on the extreme right from the beginning of the battle until the pause preceding the attack of September 18. There are, it is true, objections to continuous narrative, since it stands in the way of a bird's-eye view of the whole operation; but on the other hand the object and scope of any series of advances become unintelligible unless they are linked up from day to day. We shall therefore take the Fifth Corps as one story until it reaches the Hindenburg Line. We shall then follow the work of the other flank corps of Byng's Third Army, which was Haldane's Sixth Corps, bringing it up to the same point. It will finally, after we have established two solid bastions, be easy to deal with the central unit, Harper's Fourth Corps, which filled up the space between. We shall {84} then have a narrative which will cover four strenuous weeks in which the Third Army carried out a notable advance. [Sidenote: August 22.] It has been explained that Shute's Fifth Corps found itself with 9000 yards of river in front of it, and that on August 21 the Twenty-first Division had seized a favourable point for crossing near St. Pierre Divion. There was no further advance on the morning of the 22nd, but to the south Rawlinson's left was fighting its way to the eastern exits of Albert, and the bridges in the town were being got ready for use. All day a heavy fire was kept up on the German lines east of the river, and especially upon the rising ground called Usna Hill. As the day passed small bodies of troops began to cross the Ancre from the Fifth Corps front and to make a lodgement at the farther side. South-west of Thiepval part of the 14th Welsh from the 114th Brigade, wading over breast deep with their rifles and pouches held high, got into a trench on the farther bank and held their own. The Twenty-first Division also got some companies across at St. Pierre, while it beat off several attacks upon the north side of the river. During the night the 50th Brigade of the Seventeenth Division was slipped into the line, between Campbell's North Countrymen on the left and Cubitt's Welshmen on the right. General Shute was now ready for his great effort in crossing the river.