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 fights, and that the mobility of the machine gun batteries cannot be utilized when, from the very start, they are assigned a section to defend.

In general, it will be advisable in defense to keep the machine guns at first with the reserve, and to employ them, when necessary, to reinforce the defensive line at threatened points, to prevent envelopment, to repulse an assault, or to participate in an offensive movement.

This does not preclude their coming into action at the very opening of an engagement, for instance, where it is necessary to command important avenues of approach.

When a withdrawal under cover is assured, it will also be possible to post machine gun batteries in such a manner, in front or on a flank of the main position, that they can bring a sudden fire to bear on the area in which the opponent will in all probability post his artillery.

Machine gun fire may sometimes be employed to sweep defiladed spaces in front of the defensive line.

If the direction of the hostile attack is known, the occupation of the position should not be longer deferred. It is always risky to occupy the position in the face of hostile batteries, especially as the fire of the defender's guns is masked by the skirmishers moving forward. If the defender can manage to give the attacker the impression that the position is still unoccupied, perhaps thereby inducing him to advance less cautiously, and then surprise him with fire, a depressing moral effect far exceeding the material success may be counted upon. The firing line should be made so strong that the fire fight will have a chance of succeeding. A gradual launching of the troops should not be decided upon, as the losses are comparatively insignificant in defense, and as it is important to develop