Manual for Noncommissioned Officers and Privates of Infantry of the Army of the United States, 1917 Part 35

SECTION 5. REAR GUARDS.

A rear guard is a detachment detailed to protect the main body from attack in rear. In a retreat it checks pursuit and enables the main body to increase the distance between it and the enemy and to re-form if disorganized. The general formation is that of an advance guard reversed.

Its commander should take advantage of every favorable opportunity to delay the pursuers by obstructing the road or by taking up specially favorable positions from which to force the enemy to deploy. In this latter case care must be taken not to become so closely engaged as to render withdrawal unnecessarily difficult.

The position taken should be selected with reference to ease of withdrawal and ability to bring the enemy under fire at long ranges.

SECTION 6. FLANK GUARDS.

A flank guard is a detachment detailed to cover the flank of a column marching past, or across the front of, an enemy. It may be placed in position to protect the pa.s.sage, or it may be so marched as to cover the pa.s.sage. The object of the flank guard is to hold the enemy in check long enough to enable the main body to pa.s.s, or, like the advance guard, to enable the main body to deploy. Like all other detachments, it should be no larger than is necessary, and should not be detailed except when its protection is required.

When a flank guard consists of a regiment or less, its distance from the main body should not exceed a mile and a half. Practicable communication must exist between it and the main body. The flank guard is marched as a separate command; that is, with advance or rear guards, or both, as circ.u.mstances demand, and with patrolling on the exposed flank.

SECTION 7. OUTPOSTS.

Troops not on the march provide for their security by outposts.

The general duties of an outpost are reconnoissance, observation, and resistance.

The specific duties are:

1. To protect the main body, so that the troops may rest undisturbed.

2. In case of attack, to check the enemy long enough to enable the main body to make the necessary dispositions.

During an advance the outposts are usually detailed from the advance guard. During the retreat the outpost for the night usually forms the rear guard the next day. If the command remains in bivouac, the new outpost generally goes on duty at daybreak.

The vigilance of outpost troops must be unceasing, but they should avoid bringing on combats or unnecessarily alarming the command.

Firing disturbs the rest of troops and, if frequently indulged in, ceases to be a warning.

No trumpet signals except "to arms" or "to horse" are sounded, and all unnecessary noises must be avoided.

As a rule an outpost will not exceed one-sixth the strength of a command. For a single company a few sentinels and patrols will suffice; for a larger command a more elaborate system must be devised. The troops composing the outpost are generally divided into a reserve and several supports.

At a proper distance in front of the camp of the main body a line which offers a good defensive position is selected. This is called the LINE OF RESISTANCE, and should he so located that an advancing enemy will be held in check beyond effective rifle range in case of a small force, artillery range in case of a large force, of the main body until the latter can deploy. The reserve is stationed at some point in rear of this line, where it can be moved quickly to reinforce any point as needed. The line of resistance is divided into sections, the limits of each of which are clearly defined. A support is a.s.signed to each section, which are numbered from right to left, and occupies a position on or near the line, having special regard to covering avenues of approach. The position occupied should always be intrenched.

The reserve and supports proceed to their respective positions by the shortest routes, providing for their own protection by sending out covering detachments.

Generally speaking, about one-half the Infantry of the advance guard should be in the supports. As each support arrives at its position it sends out observation groups, varying in size from four men to a platoon, to watch the country in the direction of the enemy. These groups are called outguards. For convenience they are cla.s.sified as pickets, sentry squads, and cossack posts, and should be sufficient in number to cover the front of the section occupied by the support and connect with the neighboring supports.

A picket is a group consisting of two or more squads, ordinarily not exceeding half a company, posted in the line of outposts to cover a given sector. It furnishes patrols and one or more sentinels, sentry squads, or cossack posts for observation. Pickets are placed at the more important points in the line of outguards, such as road forks. The strength of each depends upon the number of small groups required to observe properly its sector.

A sentry squad is a squad (eight men) posted in observation at an indicated point. It posts a double sentinel in observation, the remaining men resting near by and furnis.h.i.+ng the reliefs of sentinels. In some cases it may be required to furnish a patrol.

A cossack post consists of four men. It is an observation group similar to a sentry squad, but employs a single sentinel.

As a rule not more than one-third of the support should be on outguard duty. As soon as they are sent out to their postions the support commander selects a defensive position on the line of resistance; gives instruction for intrenching same; establishes a sentinel to watch for and transmit signals from outguards; sends out patrols to reconnoiter the country to the front of his section and, if on the flank of the line, the flank; and then proceeds to make a careful reconnoissance of the section a.s.signed him, rectifying the position of outguards if necessary, seeing that they understand their instructions in case of attack or when strangers approach their posts, and pointing out their lines of retreat in case they are compelled to fall back on the support.

When the outguards are established, the members of the support may stack arms and remove equipment except cartridge belts. No fires will be built or smoking permitted unless specially authorized, or no loud talking or other noise. All patrolling to the front will be done, as a rule, from the support. The support commander should locate the position of the adjacent supports und make arrangements with the commanders for the joint defense of the line of resistance. At nights all roads and trails should be carefully covered and the country to the front and between adjacent outguards well patrolled.

The line occupied by the outguards is called the LINE OF OBSERVATION.

Outguards move to their positions providing for their own protection and so us to conceal the movement from the enemy. These positions are intrenched and are numbered from right to left in each support.

The duties of the outguard are to observe the enemy, to guard the outpost from surprise, and to make a preliminary resistance to the enemy's advance. The strength of the outguard will vary according to its object. When an important road which at night will afford a line of advance, or a bridge is to be covered, or when several posts are established from an outguard it should be of considerable strength, two squads or a platoon. When mere observation and alarm are all that is required four men will suffice. A squall is a good unit to use as an outguard; this will allow one double sentry post of three reliefs and one man in addition to the commander, who may be used for messenger service.

The outguard should be carefully concealed.

The utmost quiet should be observed, and there should be no cooking or smoking. The intervals between outguards will depend upon the situation and the terrain. The line of observation is not necessarily continuous, but all avenues of approach must be carefully guarded. The distance of the outguard from the support likewise is governed by the terrain, but in general may be said to be from 300 to 400 yards. In thick country or at night outguards patrol along the line of observation between posts. Communication between outguards and the support is by signal and messenger, in special cases by wire. Members of the outguard retain possession of their weapons and do not remove their equipment.

Sentinels from the outguard are posted so as to avoid observation, but so that they may have a clear lookout and be able to see, if possible, by day, the sentinels of the adjacent outguards.

Double sentinels are always posted near enough to each other to communicate easily in ordinary voice. Sentinels are generally on post two hours out of six. For every sentinel and every patrol there should be three reliefs, and outguards should be of a strength sufficient to allow this. The position of a sentinel should be selected with reference to observation. It may be advantageous to place a sentinel in a tree. Sentinels furnished by cossack posts or sentry squads are kept near their group. Those furnished by their pickets may be kept as far sa 100 yards away.

Reliefs, visiting patrols, and inspecting officers approach sentinels from the rear.

A sentinel on the line of observation should always have the following instructions: The names of villages, streams, and prominent features in sight and where the roads lead. The number (if any) of his post, and the number of his and of the adjoining outguards; the position of the support; the line of retreat to be followed if the outguard is compelled to fall back; the position of advance detachments and whether friendly patrols are operating in front; to watch to the front and flanks without intermission and devote special attention to unusual or suspicious occurrences; if he sees indications of the enemy, to at once notify his immediate superior; in case of imminent danger, or when an attack is made, to give the alarm by firing rapidly; by day to pa.s.s in or out officers, noncommissioned officers, and detachments recognized as part of the outposts, and officers known to have authority to do so; to detain all others and notify the outguard commander; at night, when persons approach his post, to come to a ready, halt them, and notify the outguard commander; the latter challenges, ascertains their ident.i.ty, and acts accordingly. When individuals fail to halt, or otherwise disobey, to fire upon them after a second warning, or sooner if they attempt to attack or escape; to require deserters to lay down their arms, and remain until a patrol is sent out to bring them in; to order deserters pursued by the enemy to drop their arms and to give an alarm; if they fail to obey they are fired upon; to require bearers of flags of truce and their escorts to halt and to face outward; to permit them to hold no conversation and to see that they are then blindfolded and disposed of in accordance with instructions from the support commander; if they fall to obey to fire upon them; at night, to remain practically stationary, moving about for purposes of observation only; not to sit or lie down unless authorized to do so; in the daytime, to make use of natural or artificial cover and a.s.sume such positions as to give him the best field of view; to inform pa.s.sing patrols of what he has seen; to carry his weapon habitually loaded and locked and at will.

Outpost patrols are divided into those which operate beyond the lines and those whose duty lies princ.i.p.ally within the lines.

The former, called reconnoitering patrols, scout in the direction of the enemy; the latter, called visiting patrols, maintain communication between the parts of the outpost and supervise the performance of duty on the line of observation. Reconnoissance should be continuous. Though scouts and detachments of cavalry remain in contact with the enemy, or at least push forward to a considerable distance, more detailed reconnoissance by infantry patrols in the foreground must not be neglected. Reconnoitering patrols are composed of at least two men and a skillful leader, who, in important cases, would be an officer. They obtain information, ascertain the presence of the enemy, or discover his approach.

All patrols, when they cross the line of observation, inform the nearest sentinel of the direction in which they are to advance; on their return they similarly report what they have seen of the enemy; signals are agreed upon so that they can be recognized when returning. Any ground near the line of observation which might afford cover for troops, or for scouts or spies, and the approach to which can not be observed by sentinels, is searched frequently by patrols. Definite information concerning the enemy is reported at once. Patrols fire only in self-defense or to give the alarm. Supports on the flank of an outpost position patrol the country on the exposed flank. Visiting patrols and reliefs should not march in the open, and thereby expose the position of sentinels.

During a march in the vicinity of the enemy when halts are made, special measures for protection are taken. When the halt is for a short period, less than half an hour, the advance party and support remain at ease, the point and flankers move to positions from which they can obtain a good lookout, and additional patrols may be sent out from advance parties and supports. Where the halt is for a period exceeding half an hour a MARCH OUTPOST should be formed. With an advance guard consisting of a battalion, 2 companies in the reserve, 2 in the support, the latter having as advance party one-half a company, a typical march outpost would be formed as follows: The advance party would send one platoon, four or five hundred yards to the right as outguard No.

1, the remaining platoon const.i.tuting outguard No. 2. A platoon from the head of the support would be sent a similar distance to the left as outguard No. 3. The balance of the support would const.i.tute the support of the march outpost, the reserve of the advance guard acting as reserve. On signal being given to resume the march, the various units would close in, and as soon as the advance party had a.s.sembled the march would be taken up.

SECTION 8. RIFLE TRENCHES.

Soldiers should remember that only by acting vigorously on the offensive can an army hope to gain the victory. The defensive may delay or stop the enemy, but it can never destroy him. "Troops dig because they are forced to halt; they do not halt to dig."

Trenches will frequently be constructed, without being used, and soldiers must expect this as a feature of campaigning and accept cheerfully what at times may appear as unnecessary labor.

When intrenching under fire cover is first secured in the lying position, each man scooping out a depression for his body and throwing the earth to the front. In this position no excavation can be conveniently made for the legs, but if time permits the original excavation is enlarged and deepened until it is possible to a.s.sume a sitting position, with the legs crossed and the shoulder to the parapet. In such a position a man presents a smaller target to shrapnel bullets than in the lying trench and can fire more comfortably and with less exposure than in the kneeling trench.

From the sitting position the excavation may be continued until a standing trench is secured.

The accompanying plate shows some of the more common forms of trenches in profile. Figure 1 is the simplest form of standing trench. Figure 2 shows the same trench deepened in rear, so as to allow men to walk along in the rear (deeper) portion of the trench without exposing their heads above the parapet. Figure 3 shows a cover and firing trench, with a chamber in which men can find shelter when under heavy artillery fire. When the excavated earth is easily removed figure 4 shows a good profile. The enemy's infantry, as well as his artillery, will generally have great difficulty in seeing this type of trench.

The mound or bank of earth thrown up for shelter in front of a trench is called the PARAPET. It should be at least 30 inches thick on top, and the front should slope gradually, as shown in the plate, so that sh.e.l.ls will tend to glance from it, rather than penetrate and explode. The top should be covered with sod, gra.s.s, or leaves, so as to hide the newly turned earth, which could be easily seen and aimed at by the enemy. There should be no rocks, loose stones, or pebbles on top, which might be struck by the bullets, splintering and flying, thus adding greatly to the number of dangerous projectiles, and often deflecting bullets downward into the trench. A stone wall is a very dangerous thing to be behind in a fight.

The portion of the ground in rear of the parapet and between the parapet and the trench not covered by the parapet is to rest the elbows on when firing, the rifle being rested on top of the parapet.

To obtain head cover in a trench fill a gunny sack or other bag with sand or soil and place it on top of the parapet, aiming around the right-hand side of it, or dig a small lateral trench in the parapet large enough to hold the rifle. Roof it over with boards, small logs, or brush, and heap dirt on top, aiming through the small trench or resulting loophole.

Figure 5 shows the plan of a section of a rifle trench.[7] Between the portions occupied by each squad there is often placed a mound of earth as high as the top of the parapet and projecting back into the trench. This is called a TRAVERSE and protects the occupants of the trench from fire from a flank. Bullets from this direction hit a traverse, instead of flying down into the trench and wounding several men.

[Footnote 7: The traverse should be at least 6 feet wide instead of 3 feet, as shown in figure 5.]

Trenches are seldom continuous, but are made in sections placed at the most advantageous points, as shown in figure 6. A company or battalion may occupy a single section. The firing trenches have cover trenches in rear of them, where the supports can rest undisturbed by the hostile fire until they are needed in the firing trench to repel a serious a.s.sault or to take part in a counter attack. Pa.s.sages consisting of deep communicating trenches facilitate pa.s.sage from the cover trenches to the firing trenches when under fire. These communicating trenches are usually zigzag or traversed to prevent their being swept by hostile fire.

When troops are likely to remain in trenches for a considerable time drainage should be arranged for, and latrines and dressing stations should be constructed in trenches. Water should be brought into the trenches and holes excavated in the front wall of the trench for extra ammunition.

In digging trenches men usually work in reliefs, one relief digging while the others rest, the proportion of shovelers to pick men being about 3 to 1. If a plow can be obtained to turn the sod, it will greatly facilitate the initial work of digging.