hen it commands positions that might be occupied by
hostile artillery. The guns are carefully concealed or protected and are
usually withdrawn at night.

Machine guns are useful to command approaches and check sudden advances
of the enemy.

The field trains of troops on outpost duty generally join their
organizations; if an engagement is probable, they may be held in rear.

DISTRIBUTION OF OUTPOST TROOPS

The outpost will generally be divided into four parts. These, in order
from the main body, are the reserve, the line of supports, the line of
outguards, and the advance cavalry.

[Illustration: PLATE SHOWING THE IDEAS INVOLVED IN AN OUTPOST]

The distance separating these parts, and their distance from the main
body, will depend upon the object sought, the nature of the terrain, and
the size of the command. There can be no uniformity in the distance
between supports and reserve, nor between outguards and supports, even
in the same outpost. The avenues of approach and the important features
of the terrain will largely control their exact positions.

The outpost of a small force should ordinarily hold the enemy beyond
effective rifle range of the main body until the latter can deploy. For
the same purpose the outpost of a large force should hold the enemy
beyond the artillery range.

The reserve constitutes the main body of the outpost and is held at some
central point from which it can readily support the troops in front or
hold a rallying position on which they may retire. The reserve may be
omitted when the outpost consists of less than two companies.

The reserve may comprise one-fourth to two-thirds of the strength of the
outpost.

The supports constitute a line of resisting and supporting detachments,
varying in size from a half company to a battalion. They furnish the
line of outguards.

The supports are numbered consecutively from right to left. They are
placed at the more important points on the outpost line, usually in the
line on which resistance is to be made in case of attack.

As a general rule, roads exercise the greatest influence on the location
of supports, and a support will generally be placed on or near a road.
The section which it is to cover should be clearly defined by means of
tangible lines on the ground and should be such that the support is
centrally located therein.

The outguards constitute the line of small detachments farthest to the
front and nearest to the enemy. Fo