The range should be taken by a range-finder or ascertained from neighbouring infantry or artillery. Ranging by observation of fire should be employed only when the nature of the soil is very favourable and when no other method is practicable. When a reserve ammunition cart is provided for the machine guns it will be under the orders of the machine-gun commander, who will arrange that it is placed where it can most conveniently supply the guns with ammunition; it should be screened from view, and if possible sheltered from fire. All belts shall be refilled as soon as possible after they are emptied. Should the machine-gun commander consider an escort necessary, he will at once bring the fact to the notice of his commanding officer. _With Infantry in the Attack_ _Para. 3._--The machine guns will cover the advance of the firing line by engaging the enemy from positions in close support of it. In ordinary open ground it would rarely be advisable to push them into the firing line, where they would offer a conspicuous target to the enemy; but in a broken or enclosed country, where the guns can be brought up under cover, occasions may arise when they can be usefully employed in a forward position. When the ground is favourable the gun may with advantage accompany that portion of reserves told off to cover the advance of the remainder by long-range fire. Machine guns will co-operate with the attacking infantry in the decisive fire action in endeavouring to obtain a superiority of fire. Positions on the flank of the attacking battalions or on commanding ground, if available, should be selected, as they admit of the guns remaining in action whilst the firing line is pushing forward. A position on the flank of the attacking infantry has the further advantages that oblique or flanking fire, which from machine guns is particularly effective, can be brought to bear against the enemy, whilst guns so placed are less likely to draw fire upon the attacking infantry. A change of position during the decisive fire action interrupts the fire and entails fresh laying and ranging, and therefore should be seldom resorted to unless an increased fire effect is to be obtained. At the decisive stage of the attack, fire of the greatest intensity should be continued as long as is compatible with the safety of the advancing firing line. In the event of the attack succeeding, the guns should be pushed forward at once in order to pursue the retreating enemy with their fire. In the event of failure, every effort should be made to cover the retirement of the firing line. They will assist in repelling counter-attacks to which the firing line may suddenly become exposed, and in the protection of the flanks against cavalry or counterstroke. They may be employed to give effect to holding attacks or feints, by rapid fire directed against successive portions of the enemy’s line; also to make good positions secured in the course of an action. _In the Defence_