 In the areas of the mine explosions , the British infantry found dead , wounded and stunned German soldiers . The attackers swept through the gaps in the German defences as Germans further back hurriedly withdrew . About 80 @,@ 000 British troops advanced up the slope , helped by the creeping bombardment , which threw up lots of smoke and dust , blocking the view of the remaining German defenders . The barrage moved at 100 yards ( 91 m ) in two minutes , which allowed the leading troops to rush or outflank German strong points and machine @-@ gun nests . Where the Germans were able to resist , they were engaged with rifle @-@ grenades , Lewis guns and trench mortars , while riflemen and bombers worked behind them . Pillbox fighting tactics had been a great success at the Battle of Vimy Ridge in April and in training for the attack at Messines , the same methods were adopted along with emphasis on mopping @-@ up captured ground , to ensure that bypassed German troops could not engage advancing troops from behind . In the smoke and dust , direction was kept by compass and the German forward zone was easily overrun in the 35 minutes allotted , as was the Sonne line , half way to the German Höhen ( second ) line on the ridge . The two supporting battalions of the attacking brigades leap @-@ frogged through , to advance to the second objective on the near crest of the ridge 500 – 800 yards ( 460 – 730 m ) further on . The accuracy of the British barrage was maintained and local German counter @-@ attack attempts were stifled . As the infantry approached the German second line , resistance increased . 
