At 4 a.m. on the morning of the 19th September, in a heavy rain, the 18th Infantry Brigade set out for Bourg, which was reached soon after daylight. Here, at 7 a.m., the Brigade was ordered to take over positions held by the 2nd Infantry Brigade (1st Division) and for part of the day by the 1st Infantry Brigade (1st Division). At 11pm on the 19th September the reliefs were completed.

The 1st West Yorkshires now held the extreme right of the 1st British line joining up with the left flank of the Fifth French Army, a regiment of Tireulleurs d’Afrique, African troops. A and B Companies under Major A. W. Ingles, were in the firing line which was just south of the Chemin des Dames, from west to east, C and D Companies were in support trenches echeloned in the right rear of the two forward companies.

The 2nd Durham Light Infantry were on the left of the West Yorkshires, the East Yorks. On the left of the Durhams, in front of Troyon ; and the Sherwood Foresters (2nd Notts. and Derby Regt.) in reserve just in front of the village. Brigade Headquarters were in Troyon.

Enemy snipers opened fire on the West Yorkshiremen before they were properly settled in their trenches, but no infantry attack was made. During the night [19/20th] the battalion improved the trenches and constructed overhead cover. But the trenches were poor, consisting of a series of excavations in the ground. No communication trenches existed and the firing line was connected with the supports by telephone. The Battalion stood to arms at 3-30 a.m. and shortly afterwards heavy shell fire opened on the French troops on the right flank.

About 5 a.m. the enemy launched an infantry attack against the Turcos, who, having lost most of their officers and having suffered heavy casualties during the bombardment, withdrew from their forward trenches towards Paissy, leaving the right flank of the West Yorkshires in the air.

An officers’ patrol under Lieut. C. T. Meautys was sent out to reconnoitre the right of the battalion, but was fired upon and returned. D Company under Capt. Lowe was then ordered to advance and a position was taken up on some open ground facing right, but again rifle fire broke out. It was evident the French had regained their trenches and in the uncertain morning light had mistaken the British troops for the enemy. “ D” Company, however retired to its former position. Up to this period the Battalion had suffered several casualties : Lieut. G. V. Naylor Leyland, Royal Horse Guards, temporarily attached, was wounded, one other rank was killed and twenty-six wounded. Lieut. Naylor Leyland died of his wounds on 21st September.

At 8 a.m. heavy rifle-fire was again opened on the West Yorkshires’ trenches and Col. Towsey with Lieut. Meautys went forward to see what was happening. In going forward Lieut. Meautys was mortally wounded. Once more D Company was sent forward to reinforce A and B Companies in the firing line.

Heavy firing continued all the morning and the French on the right of the Battalion again left their trenches. One company of the Royal Sussex Regiment and a squadron of the 18th Hussars were brought up to strengthen the right flank of the battalion. Telephonic communication with the firing line having broken down, touch was possible only by means of runners.

About 1-30 p.m the official diary states, a man ran back from the firing line and reported the companies in front had been captured and the Germans were advancing. From information collected it is certain that the Germans advanced under cover of the white flag on the right flank, and when our men went out to meet them they were surrounded and heavily fired on. Many were killed, a few escaped and eight officers and 436 other ranks were captured. Owing to the retirement of the French the Germans were able to get round our right flank and enfilade us with machine- gun and rifle fire. The whole affair was a mystery, but it was evident the lost companies had been first tricked and then shot down or taken prisoners.

The CO Col. Towsey, was wounded and about 3 p.m. Major Lang went forward to reconnoitre. He signalled the advance and Battalion Headquarters with C Company went forward and re-occupied the trenches which had been held by A and B Companies, having the Durham Light Infantry on their left. This position was maintained until 8pm when Battalion Headquarters and C Company were relieved by the Sherwood Foresters.

After burying their dead and as far as possible collecting the wounded, all that remained of the Battalion—five officers and 250 other ranks, were ordered into reserve in Troyon. The official list of casualties was given as follows: seven officers killed (Major A. W. Ingles, Capt. M. Fisher, Capt. J. F. P’Anson, Lieut. W. L. Eliot, Lieut. T. G. Meautys, Lieut. O. C. W. Thompson and 2nd. Lieut. E. W. Wilson), two officers wounded (Lieut.-Col. F. Towsey and Lieut. Pickering) ;~ eight officers missing ; seventy- one other ranks killed; 110 wounded and 436 missing. Major Ingles was killed whilst gallantly advancing on the trenches captured, with a few men he had collected.

The 20th September was a serious day for the 18th Infantry Brigade, for the Durham Light Infantry and the East Yorks. also lost heavily. But the line was maintained, at this period of the Aisne operations a matter of vital importance, for it involved the right flank of the British Expeditionary Force.

On the 21st, Major Lang assumed command of the battalion, which was re-formed into headquarters, C Company and one platoon. On 22nd and 23rd the battalion was in support to the Durham Light Infantry, relieving that battalion in the line on the 24th. Nine more men were killed and two wounded on the 25th, and at 8 p.m. the battalion was relieved and marched back to Pargnan, into Divisional Reserve. On the 27th reinforcements (the first) arrived, one officer and ninety-six men. At 6 p.m. on the night of the 28th, the battalion again went up into the support trenches north-east of Troyon, having 100 men in the firing line.