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.
The 51st Division was to capture Beaumont Hamel and push forward between the converging flanks of the 63rd and 2nd Divisions as far as Frankfurt Trench between Glory and Leave Avenues. The 63rd and 2nd Divisions were then to continue the attack, and join their inner flanks east of the 51st Division, thus pinching the latter out of the front line of attack.
General Harper was urged to attack with his three infantry brigades in line. He did not, however, consider that an attack launched in such strength and unsupported by a complete unit of reserve was justified. He therefore decided to attack with two brigades in line. It will be seen that the success of the attack and the length of time the Division was able to continue in the line after the attack bears ample testimony to the accuracy of General Harper’s judgment in this respect.
The 153rd Brigade was detailed to attack on the right, the 152nd Brigade on the left, with the 154th Brigade in reserve.
Two distinct objectives for the attack were selected. The first, the Green line, included the Station Road and the village of Beaumont Hamel. The second objective, the Yellow line, was the portion of Frankfurt Trench mentioned above. A further objective east of the Yellow line was given to the 63rd and 2nd Divisions.
In the attack on the Green line, three intermediate objectives were selected, known as the Pink line (the German front line), the Blue line (the German second line), the Purple line (the German third line).
Each of these lines had a separate wave detailed for its capture composed of units from the following battalions:—