make the new line the first objective. On the night of the 51st (Highland) Division attacked High Wood with two battalions of the 154th Brigade at to capture the rest of the wood and of the Switch Line. The British bombardment had begun at on 22 July, under the direction of low-flying British artillery-observation aircraft. German sources reported that the shelling was of painful accuracy and prevented the troops in High Wood from being relieved, despite the number of casualties. One battalion lost direction in the wood and had many casualties to machine-gun fire. The second battalion attacked up a dip to the south-west of the wood but was also caught by machine-gun fire from the Intermediate Line; by both battalions were back on the start line having lost The Germans in the wood also suffered greatly in the hand-to-hand fighting. III Battalion, Infantry Regiment 165 of the 7th Division and part of I Battalion, Infantry Regiment 62 of the 12th Division, were reinforced from the Switch Line by I Battalion, Infantry Regiment 91, early on 23 July. British gunners had difficulty supporting attacks on High Wood, because they had to fire over Bazentin Ridge. The low elevation of the guns meant that shells skimmed the British trenches, the margin for error was small and numerous complaints were made that British infantry casualties were caused by the British artillery. Worn guns, defective ammunition and inaccurate information about the location of British infantry positions were blamed for short-shooting. The 51st (Highland) Division pushed saps forward on 2 August, towards the Switch Line and dug a new trench near Wood Lane to the east of High Wood. August – 14 September August The 33rd Division relieved the 51st (Highland) Division and on 11 August, continued to push sap heads forward towards the Switch line and dug a new trench closer to Wood Lane to the east. Two large flame-throwers and pipe-pushers (devices to force a pipe filled with explosives underground, parallel with the surface, to create a sap when the explosives were detonated) were brought forward, as both sides patrolled the area. On 18 August, a battalion of the 33rd Division attacked the wood, using the flame throwers and thirty oil drums thrown by Livens Projectors but the flame throwers failed and the projectors were buried by British artillery-fire which fell short; the pipe pushers fouled tree roots in the wood and