In addition, High Alley, 1000 yards in length, had been cleared out and made into a first-class communication trench by the 8th Royal Scots. Further east they had also dug a completely new communication trench called Thistle Alley. The digging of these trenches was a considerable task, as the soil for the most part consisted of chalk containing countless large flints or gravel, so that every spadeful had to be loosened by the pick before it could be thrown out of the trench. On 7th August the 152nd Brigade was relieved by the 100th Brigade, 33rd Division. Owing to the intensity of the enemy's shelling of the valley at night, it was decided for the first time to carry out the relief in daylight. In spite of some apprehension caused by three German aeroplanes flying low over the lines while the relief was in progress, the experiment proved highly successful. The 152nd Brigade, in fact, did not sustain a single casualty during the operation. On 8th August the Division remained in bivouacs near Meaulte, in glorious weather. In the evening the "Balmorals," the Divisional troupe, using the tail-board of a lorry as a stage, gave a performance in the open air, which was attended by practically the entire infantry of the Division. It is doubtful if, in the whole of their highly successful career, any performance given by the "Balmorals" was more appreciated than this one. The Division had passed from sixteen days of continuous and unsatisfactory strife to an unexpected haven of rest, set in the midst of corn-lands during harvest-time. It was a real refreshment for the men to sit in the cool of a delightful summer evening and listen to "Stanley" and "Gertie," both of whom rose to the occasion admirably. So ended the first offensive operations in which the Division had been employed as a whole unit. The results had been disappointing and dispiriting to all. Over 3500 casualties, including more than 150 officers, had been sustained in two fruitless attempts to carry a German position which remained intact, in spite of many attacks by a succession of Divisions, until 15th September. The Germans had shown that High Wood could not be taken hurriedly by a direct frontal attack. Three months later General Harper was able to show that the much stronger position of Beaumont Hamel could be stormed frontally after careful preparations and with adequate artillery support. High Wood was finally overcome by a mine, which shattered the redoubt, and by tanks, which on this occasion were employed for the first time in the Great War. The mine referred to above was suggested by General Pelham Burn on the morning of 5th August as being the least costly means of subduing the redoubt. His suggestion was at once adopted. Tunnelling officers reported at brigade headquarters the same evening, the actual mining operations beginning on the following morning.