All the batteries had been shelled heavily with high explosive and gas during the preliminary bombardment, and the Observation Posts (OPs) were blinded by mist. When the bombardment shifted to the infantry's front line trenches at 06.20, the field batteries responded by firing their pre-planned 'SOS' tasks blindly into the mist. Stragglers and wounded from the retreating infantry of 14th Division brought back alarming stories, but it was decided not to withdraw the guns. C and D Batteries of CLXXVII Bde saw German infantry in the mist, caught them in enfilade and broke them up. C Battery slowly turned as the Germans passed, eventually firing into their rear, and contributed significantly to breaking up the attack.