The whole line was strained to breaking-point under the unceasing enemy pressure. Every available man was in the firing line, and the Battalion, which had been now fighting and marching without intermission for three days, was getting worn. But in spite of the enormous odds the Battalion clung on with determination, for it knew that the saving of the situation rested with itself, and attack after attack had failed to give the German masses the break-through which was essential for them. For the fourth day in succession the Germans were favoured with a thick fog which enshrouded their movements, and under cover of which they were able to prepare a further heavy blow. Early in the morning they attacked and broke through the French outpost line on the River Helot, and about 11 a.m. the lifting of the mist revealed them attacking Grover's Force east of Chauny, and also endeavouring to work round the south of the position next the Canal. This was serious, for a wedge driven in between the Chauny line and the Condren bridgehead, which was also under great pressure from the enemy, might possibly involve the loss of the Oise line, the retention of which was vital for us. Arrangements were at once made by Brigade for a further withdrawal, and this was rendered the more imperative by the rapid advance made on the left of the Corps front during the day. In this region the enemy were already threatening Guiscard, eight miles north-west of Chauny, and the security of Noyon itself was seriously in doubt. For several hours Grover's details and the tiny Condren force maintained their fight, but in the afternoon the withdrawal began in accordance with the orders already issued. Under Grover's command the mixed force was skilfully withdrawn, fighting a stubborn rearguard action, to a prepared position about 1000 yards east of Abbécourt, while the detached portion of the 2/4th Londons on Grover's left, now about 60 strong, fell back to Ognes, and marched into Besme across the Oise about midnight. Early in the afternoon Major Grover was wounded and Capt. Askham took over his command. By 4.30 p.m. the Abbécourt position, being no longer tenable, was vacated and the whole of the 173rd Group, including 2/4th and 8th Londons, 503rd Field Company, R.E. and the 6th Dismounted Cavalry Brigade, had crossed the Oise at Manicamp. About the same time the Condren garrison which had held manfully to its positions since the opening of the battle got clear across the river. Before this withdrawal was completed the whole of the Oise bridges, and also the R.E. Dump at Chauny, were demolished, and it may be remarked that during the four days of fighting not a single gun had been lost except those destroyed by enemy shell fire.