PRELIMINARY INSTRUCTIONS AS REGARDS ARTILLERY SUPPORT DURING ASSAULT.
- The Infantry Assault will be supported by a systematic bombardment of German defences by Corps Artillery and Divisional Artillery.
- A definite prearranged plan is being drawn up for the time table of the bombardment and will be issued later.
- In order to regulate the bombardment with regard to the rate of the Infantry advance, and to co-ordinate the attack throughout the various Divisions engaged, a series of Artillery lifts have been laid down with definite times assigned to them.
- These lifts are shown on attached sketch by different coloured lines. The times shown at left extremities of these lines refer to the Divisional Artillery, those at the right extremities to Corps Artillery. These lines indicate that at the times stipulated, no gun of the Divisional or Corps Artillery will be firing on any ground situated south of these lines.
- The lines have been lettered A, B, C, etc., and will be referred to within the Divisional Artillery by these letters.
- The southern edge of the barrage of fire is thus definitely established at specified times. Further instructions will be issued later as to the depth of German defences to be engaged in rear of these lines, the distribution of batteries, rate of fire etc.
- Special fronts have been allotted to five batteries per Group for wire cutting together with a strip of German defences for which they are responsible. The boundaries of these strips are shown in attached diagram.The 4.5” Howitzers will engage trenches somewhat in rear of front barrage from which fire might be brought to bear on our assaulting troops.
- The remaining batteries from each Group will be employed in dealing with any unforeseen contingencies.
- Each of these batteries will be responsible for engaging defence within the strip allotted to it as the barrage moves forward.
- During the bombardment, 18-pounder batteries will fire Shrapnel with a mixture of 20% H.E. As an indication to the Infantry that a lift is about to occur, for 50 seconds previous to each lift, all 18-pounders will fire exclusively High Explosive ammunition, namely about 5 rounds per gun.
- Throughout the advance Group Commanders will hold themselves in readiness for the possibility of having to establish a flank barrage to protect any salient that may be formed owing to some portion of the advance being checked.On the left flank the forward section of guns situated in F.17.b. will similarly be detailed for the protection of the left flank and is well sited for this purpose.
- This precaution is of special importance on the right in the vicinity of MONTAUBAN, the protection of this flank will consequently be allotted to the forward battery situated in OXFORD COPSE.
- In the event of the assault being checked, or of a German counter-attack being launched, it will be possible at any moment to establish an effective barrage on any stipulated line.On a basis of 15 batteries of 18-pounders available to establish such a barrage, the front should be covered by one 18-pounder to every 50 to 25 yards.
- Thus, for instance, should it be necessary to check a counter-attack whilst holding the POMMIERS Trench, the order would be passed to establish a barrage along ”Line D”. The barrage front of each battery being represented by the width of the strip allotted to it at that point.
- After arrival on the line POMMIERS Redoubt – POMMIERS Trench namely along lines E and D, the advance will be delayed for approximately two one hours during which time the Infantry will consolidate the line. This period will be employed by the Divisional Artillery in searching the ground to be covered in the further advance; and in dealing with any hostile preparation for a counter-attack. R.F.C. contact patrols and the Kite Balloon will be requested to furnish all possible information as regards hostile movements north of the POMMIERS Redoubt – MONTAUBAN Ridge. The further advance of the Infantry will be preceded by a barrage of 18-pounder fire starting from line ‘F’ at 2-10 and moving forward by increments of range of about 100 yards until line ’H’ is reached.
- Under cover of this curtain of fire the Infantry will advance to establish themselves on the line shown in attached sketch.
- During the final stage whilst the Infantry are consolidating their objective, the role of the Artillery will be all important. Every possible endeavour will have to be made to obtain forward observation and to establish communications, such that the Artillery barrage can be controlled from the new line.
- The above instructions are to be regarded as a general guide, and are only intended to assist Group Commanders in making necessary preparations and carrying out required registration.
- Full orders as regards lifts, barrages, etc. will be issued later.