In a War of Manoeuvre,
when infantry are frequently compelled to improvise defences on the
field of battle, by night as well as by day, the value of the
Entrenching Tool can scarcely be exaggerated. In Position Warfare, and
in the organisation of an area for prolonged defence in a War of
Manoeuvre, heavier tools and materials of all kinds are available for
the consolidation of the defences, but for the rapid construction of
temporary defences by day or by night the Entrenching Tool alone has
been proved to be highly effective. When troops are "digging
themselves in" at night with this weapon care must be taken that some
system is adopted to obtain a more or less regular line facing in the
right direction. By the extension of the men of an infantry section at
arm's length facing the enemy, and by moving the two men on each flank
two paces outwards, and the two centre men two paces backwards, and
then causing the section to dig "on the line of their toes," there will
result (even on the darkest night) a short fire trench with a central
traverse. This sectional trench can be connected at the first
opportunity with trenches dug by other sections similarly extended.
During the _Retreat from Mons_ (August-September, 1914) the
"Contemptible Little Army," under Marshal French, frequently obtained,
by means of the Entrenching Tool alone, shelter from bullets, and a
system of fire trenches which cost the pursuing Germans hundreds of
lives and materially delayed their movements.

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THE LEWIS GUN.--The Lewis gun is an automatic rifle, firing the same
ammunition as the S.-M.-L.-E. rifle, and two Lewis-gun sections are
included in each infantry platoon. The rate of fire is increased by
the automatic action of the gun, the maximum rate permitting a drum of
47 rounds to be fired in less than ten seconds, while one or two rounds
only may be fired if so required. The mobility of the Lewis-gun
sections is the same as that of other sections of the infantry platoon.

RANGES OF RIFLES AND MACHINE GUNS

_Close_ range. Up to 800 yards.
_Effective_ range. Over 800 yards up to 2,000 yards.
_Long_ range. Over 2,000 yards up to 2,900 yards.

GRENADES.--Hand grenades and rifle grenades are adjuncts to the rifle
and bayonet and the Lewis gun. Their principal use is in clearing
fortified posts, especially in Position Warfare. The _hand grenade_,
or bomb thrown by hand, is limited in range by the skill and strength
of