In preparing for the attack the destruction of the wire entanglements was one of the first considerations. In many places, owing to the undulations of the ground, this presented considerable difficulty, as direct observation could not be obtained. Even with the wire cut the attack could only be considered a difficult operation. The enemy was afforded such protection from his dug-outs that success was likely to be dependent on the attacking troops keeping close on the heels of the barrage. The artillery could not be expected to do more than drive the enemy to ground. Following the barrage closely was, moreover, in this case a difficult operation, as in few cases were the trench lines parallel. Thus the keeping of direction was certain to require skilful leading. The elaboration of the trench system also entailed a very careful detailing of objectives to the different bodies of troops, and an exact knowledge of what these objectives were. Wire-cutting was begun by the artillery and the 2" trench-mortars on 20th October, and was carried on continuously until the day of attack. Every precaution was taken to ensure that this was successful. Patrols, often accompanied by artillery officers, inspected the wire protecting the enemy front lines every night. Maps were made daily, in which the portions of the enemy wire which could be observed were shown in one of four colours, a separate colour being used to denote the varying conditions of the wire--_i.e._, satisfactorily cut, partially cut, damaged, and intact. These maps were submitted daily to Divisional Headquarters, and were passed on to the gunner officers responsible for the wire-cutting. The results were beyond expectation, and the success of the attack was in no small measure due to the skilful manner in which the artillery destroyed the entanglements. Not only was the wire under observation shot to pieces, but concealed belts of wire, whose existence was only discovered from the study of air photos, were so damaged as to give the infantry a free passage through them. Strands of cut wire lay in heaps resembling haycocks throughout the trench area. The general scheme for the attack was as follows: The Reserve Army, as the Fifth Army was then called, was to attack and establish itself on the line Miraumont-Beauregard Dovecot-Serre. Cavalry were to be held in readiness to exploit their attack in the direction of Achiet-le-Petit and Achiet-le-Grand. The IInd Corps was to attack south of the river Ancre, the Vth Corps north of the river. The Vth Corps consisted of five Divisions: the 63rd Division on the right, the 51st Highland Division and the 2nd Division in the centre, and the 3rd Division on the left, with the 37th Division in reserve.