The Twenty-third Division relieved the First and were in turn relieved by the Fifteenth in this sector, which faced the Switch Trench and Martinpuich. The Switch Line was exposed to a very heavy fire for several days, at the end of which it was attacked by this famous division, the same in number at least as that which had left nearly two-thirds of its rank and file upon the bloody slopes of Hill 70. On August 12 the advance was carried out with great dash: the 45th Brigade upon the left and the 46th upon the right. The attack was only partially successful, and the 46th Brigade was held up through the fact that the Germans had themselves been in the act of attack, so that the trenches were very strongly held. The operations continued, however, and the initial gains were enlarged, until {163} upon August 20 the whole Switch Line fell and was permanently consolidated. Leaving this left sector we must turn to the Thirty-third Division on its right, two battalions of which had got forward on July 15, as far as the line of the road connecting High Wood with Little Bazentin. The right flank of the Highland Light Infantry had been held up by fire from this wood, and in the evening the 91st Brigade of the Seventh Division had evacuated the southern edge of the wood in order to allow of bombardment. That was the position on the night of July 15. The line of the road was held all night, and early next morning the advance was ordered upon the German Switch Trench in front. It was hoped that the wood had been cleared during the night, but in the morning the Highlanders found themselves still galled by the continual fire upon their right. It was clear that the attack could not go forward with such an impediment upon the flank--one more instance of a brigade being held up by a handful of concealed men. It was hoped that the enemy had been silenced, and the attack was made, but no sooner had it developed than a murderous fire burst from the wood, making it impossible for the Highlanders to get along farther than the road. The 1st Queen's, however, being farther from the wood were able to get on to the Switch Trench, but found it heavily wired and stiff with men. Such a battalion does not take "No" easily, and their colonel, with a large proportion of their officers and men, was stretched in front of the fatal wire before it became evident that further perseverance would mean destruction. The 16th Rifles and half the 2nd Worcesters, the remaining {164} battalions of the 100th Brigade, were brought up, but no further advance was possible until the wire could be cut by the guns. About four in the afternoon of July 16 the remains of the brigade were back in the road from which they had started. The attack had failed, partly from the enfilade fire of High Wood, partly from the impassable wire.