No increase in rate of artillery fire. No unusual movements must be made in the trenches, and there must be no indication of the impending a.s.sault until the barrage is dropped.

When the trench has been taken, it should be consolidated at once to prevent counterattack. To protect this consolidation, throw out an outpost line, the posts consisting of one non-commissioned officer and 6 riflemen with a Lewis gun, about 150 to 200 yards apart and 100 to 300 yards beyond the line. These posts should be established in sh.e.l.lholes, which are to be converted into fire trenches, protected by wire entanglements, as soon as possible.

Approach trenches toward the enemy should be blockaded and hand and rifle grenadiers posted to guard them. The main captured trench should be converted at once into a fire trench facing the enemy. If it is badly knocked to pieces, a new trench may be constructed 40 or 50 yards in front of the captured line. The commander must reorganize in depth to provide supports and reserves for counterattacks. Situation reports should be sent back frequently. Rough sketches are better than messages.

Tanks follow infantry as closely as possible to deal with strong points. They are employed in sections of four.

Machine guns may be used to provide covering fire for attacking infantry, cover its withdrawal if the attack fails, fill gaps in the a.s.saulting lines, a.s.sist in the consolidation of positions and repel counterattacks.

Lewis guns are of great value in knocking out hostile machine guns.

They usually move on the flanks of the second wave of a.s.sault. Later they are used to back up patrols and to hold the outpost line while the garrison line is being consolidated.

As soon as consolidation begins, wire entanglements should be constructed. Every effort should be made to secure the objective against recapture. Any men available should be used to continue the offensive.

All commanders down to and including company commanders must keep some portion of their command as a reserve. The company commander needs his reserve to work around points which are holding against the leading lines, to protect his flanks in case the companies on his right and left are delayed in their advance and to exploit his success and gain ground to the front. He must keep it well in hand behind the company.

Battalion reserves must start with the a.s.saulting column and get across "No Man's Land" as soon as possible; they must not get out of hand. Such a reserve is usually checked in the vicinity of the enemy's front line trench, where it can be thrown in to a.s.sist the advance or extend a flank as needed.

The brigade reserve is kept well in hand just clear of the friendly front line and support trenches. Reserves of companies and battalions must start moving over the top of the ground with the rest of the a.s.saulting troops.

Defense Of Trenches.--The latest methods consist in constructing, supporting and strong points at the most favorable points to be held, such as villages, woods, etc. These are separated by intervals not too great for mutual support. They are of such resisting power that they must be taken before the attack can progress. In the intervals between them fire and communicating trenches are constructed, but these are only held lightly. Dummy trenches may be placed in these intervals.

Lines of the various works are so traced that they bring enfilading fire on troops attacking adjacent positions. The lines need not be continuously occupied, but the obstacles extend in an unbroken line along the whole front. Wire entanglements are set in front of important positions in belts 20 feet wide, in two or three rows, each 20 yards apart.

Each supporting point usually is occupied by a battalion, and consists of a series of trenches formed into strong points, each held by a garrison of one or more platoons or a company. The supporting points are from 600 to 800 yards in depth and have a front of 600 to 1,000 yards. The first line of strong points is occupied by one or two companies in firing and cover trenches, while the remainder of the battalion occupies the support and reserve trenches. Bomb-proofs are built along the cover trenches and are connected with the firing trenches. Approach trenches are protected on both flanks by wire entanglements. Strong points in support and reserve trenches are prepared for an all-around defense and divided into two or more separate strong points by wire entanglements.

A body of infantry attacked is to oppose to the a.s.sailant its high powered weapons, machine guns, automatic rifles, rifle grenades and hand grenades and to reserve for the counter attack the grenadiers and riflemen. There is always one line upon which the resistance must be made with the greatest energy; for its defense the following methods have been found successful. Machine guns should be placed where they can secure the best flanking fire, and every one put out of action should immediately be replaced by an automatic rifle. If machine gun barrage fire is to play its role successfully at the moment of a.s.sault, the guns must survive the bombardment. Their protection is secured by placing them under shelter during the bombardment and making their emplacements as nearly invisible as possible. They should be echeloned in depth as far as practicable. They are generally placed in re-entrants of the firing trenches and cover the intervals between the adjoining supporting and strong points. Where the ground will permit they are often placed in concealed positions 20 to 30 yards in front of the trenches, to break up attacks made by hostile infantry.

Not too many should be placed in the front line, and they should be echeloned in depth so as to confuse their disposition. The value of machine guns depends on the possibility of using them suddenly for brief periods, and in using them as long as they are effective.

Machine guns disposed for flanking fire must be well covered by grenadiers; this is also true of automatic rifles.

Automatic rifles, rifle grenades and hand grenades are used to const.i.tute a barrage to keep back the enemy. The entire front should be defended by a barrage of hand grenades, while the barrage of automatic rifles and rifle grenades is superposed farther to the front, up to 400 yards.

All riflemen and those grenadiers not employed in forming barrages are reserved to make a counterattack.

Companies on the second line operate on similar principles; machine guns, automatic rifles and rifle grenades are arranged so as to cover every portion of the first line that might be invaded. After a short preparation by fire from these, the grenadiers and riflemen make the counterattack.

The captains in charge of the two lines are responsible for the arrangement of the machine guns, automatic rifles and rifle grenades, the distribution of barrages and the distribution of groups for the counterattack. The real strength of the defense consists, not in holding the fire and cover trenches, nor even the support trenches, but in holding the supporting and strong points until the counterattack can be launched.

Liaison.--The question of liaison in battle is of the utmost importance, and complete co-ordination of the different arms is absolutely necessary. Each battalion sends an officer or non-commissioned officer and a cyclist to the colonel, and each colonel sends a soldier to the battalion commander.

The princ.i.p.al means of communication are the telephone, telegraph, wireless, aeroplane, mounted messengers, autos and motorcycles; and at the front runners, visual signals, rockets and carrier pigeons.

Each battalion commander is connected by telephone with each company commander, with the artillery observers, with the artillery commander, with his own colonel and with the adjacent battalions on either side.

The signallers of a.s.saulting companies move with the company commander. All signallers should be given a special training in repeating a message several times to a known back station which may not be able to reply forward.

At the commencement of the a.s.sault the pigeons and pigeon carriers must be kept back at battalion headquarters, and sent forward as soon as the position has been gained.

Runners can be relied upon when all other means fail. They must be trained with their companies. Runners should be lightly equipped and wear a distinctive mark. They must be familiar with all the princ.i.p.al routes to all the princ.i.p.al centers within their battalion sector. The quicker they go the safer they are. Company and platoon runners must go forward with their respective commanders. Messages to be carried long distances will be relayed. Never send a verbal message by a runner; ignore any received; all messages must be written.

Company and battalion commanders must be prepared to a.s.sist artillery liaison officers in getting their messages back. Liaison officers must be exchanged by all the a.s.saulting battalions with the battalion on either flank.

Trench Orders.--(Battalion): Trenches are usually divided into a certain number of bays; the number of men to defend these bays depends upon the length of trench allotted to each company. Each section is detailed to guard a certain number of bays.

Non-commissioned officers and men must always wear their equipment by day and night. Every company will "Stand To" arms daily one-half hour before dusk and one-half hour before dawn, and will remain until dismissed by the company commander.

The enemy's trenches are so close that it is very important for the men to have their rifle sights always at battle sight, so that there will be no necessity to alter their sights in case of alarm. By night all bayonets are to be fixed and half of the men on duty in the trenches are to be sitting on the firing platform with their rifles by their side. In case of attack, especially at night, it should be impressed upon the men that they fire low.

Section commanders are responsible that the men under their command have sufficient standing room for the purpose of firing over the parapet. They must have a clear field of fire, and not only be able to see the enemy trenches but the ground in the immediate vicinity of their trench. When making new trenches parapets should be at least five feet thick at the top in order to be bullet proof.

Repairs or alterations of the parapet should be reported at once by the section commander to the platoon commander, who will report it to superior authority. Repairing of trenches, fatigue, etc., will be carried on either by day or night according to company arrangement.

Certain hours will be allotted for these tasks and no man is to be employed upon any kind of work out of these hours. No man should leave his post in the trenches at any time without the permission of the non-commissioned officer in charge of that post. At night there should be at least one sentry post to each ten yards of parapet. At night, double sentries should be posted if possible, and no sentry should be kept on duty for longer than an hour at a time. The arrangement should be such that when one sentry is doing his last half hour, his comrade will be doing his first half hour.

Sentries at night should always have their rifles resting on the parapet, ready to fire at a moment's notice. As few sentries as possible should be posted by day, so as to give as much rest as possible to the remainder of the men.

By day any existing loop-holes may be used by a sentry for observation purposes, but this must be strictly prohibited at night, when the sentry must look over the parapet. If a sentry is continually fired at, the section commander will post him in another position, but not too far from his original position. There is no excuse for a man going to sleep on sentry duty; if he is sick he should report the fact to the non-commissioned officer, who will report to superior authority.

An armed party of the enemy approaching the trench under a flag of truce should be halted at a distance, ordered to lay down their arms, and the matter at once reported to the company commander. If the party fails to halt when ordered to do so, or does not convey a flag of truce, they should be fired upon. An unarmed party should be halted in the same way. It is not necessary to challenge at night; open fire at once. This is modified only by special instructions.

Men especially picked for listening patrols and sharp-shooters will be given special privileges. All loud talking must be checked at night by officers and non-commissioned officers. All working parties must wear their equipment and carry their rifles. All picks and shovels will be returned after use to the company store room. Ration parties and parties carrying materials for repairs, etc., need not wear their equipment or carry rifles; they should be accompanied by a fully armed non-commissioned officer as an escort. Not more than 20 men are to be away from the company at one time; one non-commissioned officer and four men per platoon.

Rifles must be kept clean and in good condition while in the trenches.

They will be cleaned every morning during an hour appointed by the company commander for the purpose. Platoon commanders will be responsible that section commanders superintend this work. All rifles except those used by sentries are to be kept in racks during the day.

Trenches must be kept in sanitary condition. Platoon commanders will be responsible for the latrines in their sections of the trenches. All water for drinking and cooking is to be taken from a water cart or tank provided for this purpose.

Stretcher bearers will be stationed at a place designated by the commanding officer. No soldier will be buried nearer than 300 yards from the trenches.

In every platoon a non-commissioned officer will be detailed for duty by day; he will do no night duty. He will post the day sentries and see that they are on the alert and carry out their orders correctly.

He will be responsible for the cleanliness of his lines and will frequently visit the latrines. He will see that all loose ammunition is collected.

The platoon commander will always send a non-commissioned officer to draw rations and he will be responsible for their delivery.

The pa.s.sing along of messages by word of mouth will not be used. All messages should be written.

Special instructions will be issued as to precautions against gas.

Selection of Site.

(a) Fire trench should be selected with due regard to tactical requirements and the economy of men.

(b) Every fire trench should have a good field of fire, at least 250 yards.

(c) The trenches should have the best possible cover.

(d) The forward position on a slope for the first line has the best advantage. The support trench should be on the reverse slope from 100 to 600 yards in rear of the first line to prevent direct observation and to be practically free from artillery fire. The reserve trench is usually from 1/2 to 1 mile in rear of the first line. Remember that the first line, the support line, and the reserve line are all fire trenches. Do not put them on a crest.