 On the right of IX Corps , the 36th ( Ulster ) Division attack on the front of the 107th Brigade , was supported by three mines at <unk> and the big mine at <unk> , 800 yards ( 730 m ) further north . The 109th Brigade on the left was helped by a mine at Peckham House . The devastated area was crossed without resistance , German survivors being stunned by the mine explosions . The 16th ( Irish ) Division attacked between <unk> Farm and the <unk> – Wytschaete road . The mines at <unk> and the two at Petit Bois devastated the defence ; the mines at Petit Bois on the left were about 12 seconds late and knocked over some of the advancing British infantry . On the left of IX Corps , the 19th Division , north of the <unk> – Wytschaete road , attacked with two brigades into the remains of Grand Bois and Bois <unk> . Three mine explosions at <unk> allowed the infantry to take a dangerous salient at Nag 's Nose , as German survivors surrendered or retreated . 
