es have been provided in
some trenches as shown in (Fig. 16).

[Illustration: Fig. 18

_Store Recesses for Water, Hand-Grenades, Reserve Ammunition, Machine
Guns, Range Finders, Blankets, etc._ (From _Field
Entrenchments_--Solano.)]

=1151. Parados.= Instead of shrapnel, explosive shell is most
frequently used in the European War. This necessitates the addition of
a parados to the fire trench to protect against the back blast of high
explosives. This is shown in (Figs. 8 and 17).

An interesting development in cover for the firing line is shown in
dugouts constructed in the fire trenches in the European war. These
dugouts are deep underground and shelter from 3 to 8 men each (Fig.
19). These dugouts will be discussed more in length under cover
trenches.

[Illustration: Fig. 19]

=1152. Head cover= is the term applied to any horizontal cover which
may be provided above the plane of fire. It is obtained by notching or
loop-holing the top of the parapet so that the bottoms of the notches
or loopholes are in the desired plane of fire. The extra height of
parapet may be 12 to 18 inches and the loopholes may be 3 to 3-1/2
feet center to center.

Head cover is of limited utility. It increases the visibility of the
parapet and restricts the field of fire. At close range the loopholes
serve as aiming points to steady the enemy's fire and may do more harm
than good at longer ranges. This is especially the case if the enemy
can see any light through the loophole. He waits for the light to be
obscured, when he fires, knowing there is a man's head behind the
loophole. A background must be provided or a removable screen arranged
so that there will be no difference in the appearance of the loophole
whether a man is looking through it or not. Head cover is advantageous
only when the conditions of the foreground are such that the enemy can
not get close up.

=1153. Notches and loopholes=, Figs. 20-22, are alike in all respects,
except that the latter have a roof or top and the former have not. The
bottom, also called =floor= or =sole=, is a part of the original
superior slope. The sides, sometimes called =cheeks=, are vertical or
nearly so. The plan depends upon local conditions. There is always a
narrow part, called the =throat=, which is just large enough to take
the rifle and permit sighting. From the throat the sides diverge at an
angle, called the =splay=, which depends upon the field of fire
necessary.

[Illustration