r the withdrawal or
retreat of the main body, may first be compelled to take up a
defensive position behind which the main body forms up and moves off.
It may be forced to withdraw from this position by successive skirmish
lines, gradually forming up in column on the road as it clears itself
from fighting contact with the enemy.

The rate of march of the rear guard depends upon that of the main
body. The main body may be much disorganized and fatigued,
necessitating long halts and a slow marching rate.

=1050. Action of the Rear Guard.= The withdrawal of defeated troops is
delayed, if possible, until night. If it becomes necessary to begin a
retreat while an engagement is in progress, the rear guard is
organized and takes up a defensive position generally behind the
fighting line; the latter then falls back and assembles under cover of
the rear guard.

The rear cavalry gives away before the enemy's pursuit only when
absolutely necessary, maintains communication with and sends
information to the rear guard commander, and pays special attention to
the weak points in the retreat, namely, the flanks. It makes use of
every kind of action of which it is capable, according to the
situation, and unless greatly outnumbered by hostile cavalry, it
causes considerable delay to the enemy.

When the enemy is conducting an energetic pursuit the rear guard
effects its withdrawal by taking up a succession of defensive
positions (that is, where the nature of the ground enables the rear
guard to defend itself well) and compelling the enemy to attack or
turn them. (It should be understood that these successive defensive
positions must, in the case of a large force, be from two to four
miles apart and in the case of a small force at least one-half mile
apart--not a few hundred yards as is frequently attempted in peace
maneuvers.)

When the enemy's dispositions for attack are nearly completed, the
rear guard begins to fall back, the cavalry on the flanks being
usually the last to leave. The commander designates a part of the rear
guard to cover the withdrawal of the remainder; the latter then falls
back to a new position in rear, and in turn covers the withdrawal of
the troops in front. These operations compel the enemy continually to
deploy or make turning movements, and constantly retard his advance.

The pursuit may be further delayed by obstacles placed in the enemy's
path; bridges are burned or blown up; boats removed or destroy