d on the reverse slope of
the hill.

In many instances the first line trenches consist of as many as four
or five lines of trenches running in a general lateral direction and
connected by deep narrow communicating trenches. The depth between the
first and last of these trenches is, in some instances, not over a
hundred yards. Sign boards are necessary at short intervals to prevent
the soldiers from getting lost. The effect of having so many
alternative firing trenches is to make it extremely difficult for an
enemy to advance from, or even to hold one of them, even when he gains
a footing, as he would be swept by fire from the supporting trenches
in rear and also by flanking fire from the adjacent trenches.

=1161. Location.= There are two things to be considered in locating
trenches: (1) The tactical situation, and (2) the nature of the
ground. The first consideration requires that the trenches be so
located as to give the best field of fire. Locating near the base of
hills possesses the advantage of horizontal fire, but, as a rule, it
is difficult to support trenches so located and to retreat therefrom
in case of necessity. While location near the crest of hills--on the
"military crest"--does not possess the advantage of horizontal fire,
it is easier to support trenches so located and to retreat therefrom.
Depending upon circumstances, there are times when it will be better
to intrench near the base of hills and there are other times when it
will be better to intrench on the "military crest," which is always in
front of the natural crest. The construction of trenches along the
"military crest" does not give any "dead space"--that is, any space to
the front that can not be reached by the fire of the men in the
trenches.

Whether we should construct our trenches on high or low ground is a
matter that should always be carefully considered under the particular
conditions that happen to exist at that particular time, and the
matter may be summarized as follows:

The advantages of the high ground are:--

1. We can generally see better what is going on to our front and
flanks; and the men have a feeling of security that they do not enjoy
on low ground.

2. We can usually reenforce the firing line better and the dead and
wounded can be removed more easily.

3. The line of retreat is better.

The disadvantages are:--

1. The plunging fire of a high position is not as effective as a
sweeping fire of a low one.

2.