During the morning Lieut.-Col. Campbell, the Adjutant and the four company officers went forward to reconnoitre the forward area, visiting in turn 169th Brigade Headquarters at Dormy House, and Headquarters of the Battalion in line of the 53rd Brigade at Stirling Castle. It had been intended also to reconnoitre the ground over which the advance was to be made, but such was the intensity of the enemy's artillery and machine-gun fire that this was impossible, and the company commanders were compelled to return to their companies in ignorance of what lay before them. Later in the day Lieut.-Col. Campbell was ordered to report to 53rd Brigade Headquarters, but was unluckily hit on his way back, near Zillebeeke Lake. Although badly hit he made his way back to the Battalion, but being unable to carry on was succeeded in the command by Major A. F. Marchment, M.C. (1/1st Londons).
At seven that night the Battalion moved forward from Dickebusch to Château Segard, the move being completed by 11 p.m. Shortly after dawn on the 15th the forward move was continued to Railway Dugouts, in the cutting between Shrapnel Corner and Zillebeeke Lake, and here the Battalion remained during the day.
The 15th August was occupied in issuing battle equipment and rations to the companies, while Lieut.-Col. Marchment took the opportunity of conducting a reconnaissance of the forward area and communications, and of issuing his operation orders. These were explained to company commanders as adequately as time permitted, but it must be borne in mind that when the Battalion moved forward to the assault the following morning no company or platoon officer had been able to see the ground over which he was to lead his men. At 6.30 p.m. the 1/4th Londons left Railway Dugouts in battle order for the assembly area at Clapham Junction with guides supplied from the 53rd Brigade. A great deal of heavy shelling, in which four men of B Company were hit, was experienced during the advance, and in breasting a ridge near Sanctuary Wood the Battalion had to pass through a barrage put down by the Germans. Aided by the excellent discipline of the troops, however, company commanders were able to split up their companies within a few seconds, and no loss was sustained. By ten o'clock the Battalion was concentrated with A, B and C Companies in the tunnel under the Menin Road, and D Company in the trench south of the road. Battalion Headquarters and part of C Company were in the trench on the north side of the tunnel. There was no defined line of trenches in this area, the front being held by isolated shell hole posts, and the assembly was to be made on tape lines laid down under staff arrangements. The lack of shelter thus made it necessary to keep the Battalion under such cover as was obtainable till the last possible moment. During the evening an officer of each company reconnoitred the route from the concentration area to the tape lines, assistance being rendered by the 6th Royal Berkshires, and No Man's Land in front of the line of assembly was patrolled until shortly before zero hour.
The intention was to advance in a practically due east direction, while at stated points in the line of advance platoons would halt one by one, each establishing itself in a strong point, until finally, when the last platoon reached its halting point, the whole Battalion would be deployed in a line of outposts, all of which would turn to their right and face south. This advance, being made on a front of two companies, would result in a double line of posts of which the left flank would rest on Black Watch Corner in touch with the 169th Brigade, while the right flank would join hands with the 7th Bedfords in the corner of Inverness Copse.
At 3.15 a.m. on the 16th August companies began to form up on the tape lines, the assembly being completed by 4.20 a.m., when the troops were lying down in the open under a continuous and fairly heavy shell fire and a galling machine-gun fire from the direction of Inverness Copse. About 22 casualties occurred under this fire before zero hour at 5.45 a.m. The order of battle was as follows: A. Company (Spiers) on the right and B Company (Stanbridge) on the left in front; with D Company (H. N. Williams) on the right and C Company (Rees) on the left in support.
The attack was to be delivered along the whole battle front at 5.45 a.m. under cover of a creeping barrage, supported by machine-gun barrage and heavy gun fire on the enemy back areas. At zero hour the British barrage came down, well distributed and of terrific intensity. It was hoped that the danger points in Inverness Copse would be put out of action by our artillery, so that the task of the 7th Bedfords would be an easy one, but calculations in this respect were soon found to have been mistaken. The leading companies of the 1/4th Londons got away from the mark at zero, in good order and well up to the barrage, but almost immediately came under a hail of lead from Inverness Copse. The attack of the 7th Bedfords, of such vital importance to the success of the whole operation, had failed. The artillery fire had not produced the expected effect on the enormously strong enemy posts over which the barrage had passed harmlessly, and the 7th Bedfords were repulsed with loss, thereby leaving the 1/4th Londons completely exposed to the full force of the enemy's nest of machine-guns on their right flank.
Within a few minutes 5 officers and 40 N.C.O.'s and men of A and B Companies were casualties, but the survivors pushed forward steadily, though a certain amount of delay caused by the gaps so suddenly torn in their ranks was inevitable. The gallantry displayed by all ranks under this devastating machine-gun fire, to which was added enemy shell fire of great intensity, was unsurpassed, but under such a storm of bullets at close range nothing could live, and the Battalion was brought to a standstill about 200 yards from starting-point, in an old German trench which skirted a ruined farmhouse about midway between Inverness Copse and Glencorse Wood.
A party of some 60 men of all companies managed to gain shelter in Jap Avenue. Here they were organised by 2/Lieut. H. E. Jackman, under whom a strong post was consolidated and an attempt made to push forward along the trench. This proved unsuccessful owing to the continued intensity of the enemy machine-gun fire and the accuracy of his sniping. Further attempts by other companies to advance were also fruitless, and the Battalion was forced to content itself with hanging on to these small gains, from which at intervals it was able to engage with Lewis gun and rifle fire small bodies of the enemy in the open near the east end of Glencorse Wood.
An attempt was made to re-establish the situation by an attack, for which the 53rd Brigade was called upon, through Inverness Copse from south to north, but so terribly reduced in numbers were its battalions that Brigade reserve was limited to two weak platoons and further action was found to be for the moment impossible.
In the centre the leading waves of the 169th, after some resistance in Glencorse Wood which they overcame, succeeded in penetrating Polygon Wood, where they probably gained their objective. The second waves on approaching the Wood were, however, met with intense fire from front and flanks, and a few minutes later a heavy counter-attack developed which drove back the assaulting troops to the middle of Glencorse Wood. A further counter-attack in the evening forced the Brigade back to its assembly line.