(iv) To concentrate a powerful fire from an extended frontage on an important locality in the hostile position.
(v) To oblige the enemy to expose his dispositions.
(vi) In pursuit.
(vii) In siege warfare, to harass the enemy.
4. Long range fire requires a large expenditure of ammunition, and it is necessary, if it is to produce a corresponding effect, and if waste of cartridges is to be avoided, that it should be carefully controlled and concentrated, and that the distance should be accurately ascertained; or if this is not possible, that a considerable depth of ground should be evenly swept by fire by the use of combined sights.
135. Co-operation between Artillery and Infantry in the Attack.
1. Both in attack and defence the most intimate co-operation between the artillery and infantry must be aimed at, if the latter are to derive the full advantage of the support of the former. In the preliminary stages of the attack the advance of the infantry will draw the fire of the defence and thus find a target for the artillery, whilst the fire of the latter, combined with that of other covering bodies, will enable the firing line to approach in extended order towards the enemy’s position without undue loss.
2. In the subsequent fire action the artillery and infantry must co-operate in shaking the fire of the defence so as to admit of the further advances of the firing line, which should take advantage of the slackening of the fire of the defence, caused by the fire of the quick firing artillery covering the advance, to push in closer to the enemy’s position.
3. At the crisis of the engagement, preparatory to the assault, the artillery and infantry must combine to bring the heaviest possible fire to bear against the point or points against which it is proposed to drive home the attack, in order that a superiority of fire over the defence may be rapidly established; and at no other time is the close co-operation so important, if the full effect of the two arms is to be obtained.
136. The Decisive Attack.