German artillery positions and the second () (Contour Position) position were not visible to British ground observers. For observation over the rear slopes of the ridge, were concentrated in II Brigade RFC and eight balloons of II Kite Balloon Wing were placed behind the British front line. The Second Army artillery commander, Major-General George Franks, co-ordinated the corps artillery plans, particularly the heavy artillery arrangements to suppress German artillery, which were devised by the corps and divisional artillery commanders. The Second Army Report Centre at Locre Château was linked by buried cable to each corps report centre, corps heavy artillery headquarters, divisional artillery headquarters, RFC squadrons, balloon headquarters, survey stations and wireless stations. Responsibility for counter-battery fire was given to a counter-battery staff officer with a small staff, who concentrated exclusively on the defeat of the German artillery. A conference was held each evening by the counter-battery staffs of divisions and corps, methodically to collate the day's reports from observation aircraft and balloons, field survey companies, sound ranging sections and forward observation officers. Each corps had a counter-battery area, which was divided into zones and allotted to heavy artillery groups. Each heavy artillery group headquarters divided their zones into map squares, which were allotted to artillery batteries, to be ready swiftly to open fire on them.