he direction of
the railroad trestle. Your men break and run east through the corn and
you follow, but lose sight of them. When you cross the railroad fill
you are fired on from the direction of the bridge. You finally stop
behind the railroad fill on the quarry switch, where two of your men
join you.

=Sergeant Allen:= I would start south to rejoin the company and
report.

=Captain:= That would be a mistake. It would require a long time for a
second patrol to make its way out over unknown ground, filled with
hostile patrols, to a point where they could observe anything in rear
of the hostile flank. You are now fairly familiar with the ground, you
also know about where the hostile patrols are and you have two men
remaining. After a brief rest in some concealed place nearby, you
should start out again to make an effort to determine the strength of
the troops in rear of the hostile flank near you, or at least remain
out where you could keep a sharp lookout for any attempted turning
movement by the enemy. Should anything important be observed you can
send back a message and two of you remain to observe the next
developments before returning. The information you might send back and
the additional information you might carry back, would possibly enable
your own force to avoid a serious reverse or obtain a decided victory.

Your work would be very hazardous, but it is necessary, and while
possibly resulting in loss of one or two of your men, it might prevent
the loss of hundreds in your main force.

CHAPTER V

THE SERVICE OF SECURITY

(Based on the Field Service Regulations.)

General Principles

=1020. The Service of Security= embraces all those measures taken by a
military force to protect itself against surprise, annoyance or
observation by the enemy. On the march, that portion of a command
thrown out to provide this security is called an advance, flank or
rear guard, depending on whether it is in front, to the flank or in
rear of the main command; in camp or bivouac, it is called the
outpost.

The principal duties of these bodies being much the same, their
general formations are also very similar. There is (1) the cavalry
covering the front; next (2) a group (4 men to a platoon) or line of
groups in observation; then (3) the support, or line of supports,
whose duty is to furnish the men for the observation groups and check
an enemy's attempt to advance until reinforcements can arrive; still
farther i