Brigade, which had been pushed forward in readiness, retired again to the west of the St. Quentin Canal.
Now that the Fonsomme line had been breached and it was known that no organized system of defence lay in front of our troops, it seemed that another favourable opportunity had come, and word was immediately sent back to the 5th Cavalry Brigade to advance and exploit our success. This Brigade, commanded by Brigadier-General N. Haig, C.M.G., and composed of the Scots Greys, 12th Lancers, and 20th Hussars, were, however, a considerable distance behind the line, and some time elapsed before they were able to come into action, by which time the enemy had recovered from their surprise and their resistance had considerably stiffened. It was then clear that Cavalry would be unable to dislodge the machine-gun posts on the high ground beyond our front, and the Brigade was withdrawn into Divisional Reserve and later dismounted and used to reinforce the 137th Brigade, taking up position, together with the 9th Corps Cyclists, in the Fonsomme line.
At noon, the situation appears to have been as follows:—The 139th Brigade were holding Montbrehain and their final objective generally, with a long defensive flank thrown back in the direction of Wiancourt, and with their right flank in the air altogether, since touch could not be obtained with the Stafford Brigade. The latter Brigade, which had reached its objective early in the morning, had been forced to fall back and now occupied a line considerably in rear of that held by the 139th Brigade. Of the supporting Brigade—the 138th Infantry Brigade—one battalion (the 4th Leicesters) was now ordered up to strengthen the left flank of the 139th Brigade, and the 5th Lincolns moved up to take the place of this battalion in the Beaurevoir-Fonsomme line. The remaining battalion
