Ordinarily infantry intrenches itself whenever it is compelled to halt
for a considerable time in the presence of the enemy. (Infantry Drill
Regulations.) Trenches are constructed with a view of giving cover which
will diminish losses, but they must not be so built or placed as to
interfere with the free use of the rifle. A good field of fire is the
first consideration. The construction of a trench is simple, but the
cation of it is difficult. If possible, trenches are laid out in
Intrenchments usually take the following form:
(1) Hasty Cover. Constructed by troops with the tools they carry on
their person. It is a shallow trench with a parapet at least three feet
thick and one foot high. It furnishes cover against rifle fire, but
scarcely any against shrapnel.
(2) Fire Trench. It should be deep and narrow with the parapet flat
and concealed. While in it, the troops fire at the enemy; hence the name
Usual forms of fire trenches are as shown in the following illustration:
(3) Support Trenches. The supports sleep and live in these trenches;
hence they are covered. The cover (roof) must be thick enough to afford
protection from high angle artillery fire. It is placed as near the fire
trench as possible.
(4) Approach Trenches. These connect fire trenches with the support
trenches and the support trenches with any trenches in rear where
natural covered communication is impracticable.
They are zig-zagged to escape being enfiladed. (That is, to prevent one
explosion from doing too much damage in a single trench.) During an
engagement, troops by using these trenches can go safely to the help
of the troops in the fire trenches. They are usually deep and narrow.
(5) Intermediate Trenches. They are constructed in rear of the support
trenches when the ground renders it possible to offer a stubborn
resistance between the support and the reserve trenches. They are
constructed like fire trenches.
(6) Reserve Trenches. Constructed like the fire trenches and occupied
by the local reserves who live in deep dug-outs. The intermediate and
reserve trenches are often merged into the support trenches. All are
protected by barbwire entanglements. No set plan of trenches can be
used. The topographical features of the ground must govern.