Chapter III

Sector and Trench Duties

=Plan of Defense=—Definition—Principles—Form of—=Details of Trench Duty=—Guard Duties—Sentinels—Reconnoitering Patrols—Observers— Attrition—Fighting Patrols and Raids—Arms, Equipment, and Ammunition—Activities of the Troops—Reports—=Use of Infantry and Artillery Weapons, and Liaison=—Machine Guns—Trench Mortars— =Artillery Support=—Use—Barrage—Liaison—Instructions for Sentinels—Watchers—Observers 62