the battle, and unless
infantry co-operate, the artillery is not likely to produce any
decisive effect. Long-range machine-gun fire is an important auxiliary
to the artillery in covering and supporting the advance of attacking
infantry. Enfilade fire, the most telling of all, is more easily
brought to bear than of old owing to the increase in the effective
range and in the rate of fire. Supports and local reserves will
usually co-operate most effectively with forward troops by bringing
fire to bear upon the flank of such bodies of the enemy as are holding
up a movement by frontal fire. During the counter-attack for the
recapture of _The Bluff_, in the Ypres Salient (March 2, 1916) by
troops of the 3rd and 17th Divisions, the right and centre gained their
objectives. The left attacking party, at the first attempt, failed to
reach the German trenches, but those who had penetrated to the German
line on the right realised the situation and brought a Lewis gun to
bear on the enemy's line of resistance, completely enfilading his
trenches, and thus enabling the left company to reach its goal.

MOVEMENT.--The influence of movement is inseparable from that of fire,
as it enables fire to be opened and is a means of escaping the full
effects of fire; while it is often possible to move one unit only in
conjunction with the fire of another. It can also be used to relieve
one unit from the effects of fire concentrated upon it by moving
another unit against the enemy. A steady and rapid advance of troops
has the twofold effect of closing to a range from which an ascendency
in the fire-fight can be secured, and also of reducing the losses of
the advancing force, for if the troops remained stationary in the open
under heavy fire, at a known range, the losses would clearly be greater
than if they advanced, and would be suffered without gaining ground
towards the objective, while the closer the {40} assaulting line gets
to the objective, and the steadier its advance, the less confidence
will the enemy have in their power to stem the advance, and the fewer
casualties will be suffered in consequence. No "sealed pattern" is
laid down as to the movement and formation of infantry under fire, but
certain definite principles are put forward in the text-books. Where
security is the first need, as in the case of protecting forces
(advanced, flank, or rear guards), movement should be effected by
bounds from one tactical position to another