 Complete the following phrase:  On 22 August 39th DA began moving south by rail to join First Army in the Arras area and on 25 August it was placed under Canadian Corps for the Battle of the Scarpe. The guns were pre-positioned on 2425 August, then the detachments moved up late on 25 August. The following days assault was made at 03.00 behind an excellent creeping barrage of 18-pdrs with the 4.5inch howitzers firing in front. The attack was successful, and the guns moved up in close support on 26 and 27 August. On 27 August Lt-Col Lord Alfred Browne commanding CLXXXVI Bde was killed in action. The Canadians advanced behind another creeping barrage on 28 August, and the guns continued to follow in support on 29 and 30 August, breaking up several counter-attacks. The forward movement continued in early September the 