CHAPTER 15.

Trench Warfare.

General Principles.

1. Defense may be made in depth by all organizations, down to and

including the platoon, or it may be made laterally.

2. The smallest active segment, be it only three men, must have a

chief and a second in command, who is responsible for the proper

upkeep and defense of the segment. All occupants of active segments

must know all instructions which should be simple.

3. Any troops in charge of a portion of trench must never abandon it,

no matter what happens, even if surrounded.

4. All ground lost must be retaken at once by immediate counter attack

launched by the unit which lost the ground. As a matter of fact a

counter attack is difficult for a platoon or company; it is really

necessary for it to be made by a battalion.

5. Each company must provide for emplacements for mine throwers to be

served by the artillery and for pneumatic guns to be served by their

own men.

Instructions to be Issued by Battalion Commander.

1. Disposition of companies in sector assigned (best done by sketch

showing sectors assigned to companies).

2. Special orders to companies (concerns field of fire to be obtained

not only in own sector, but also in those adjoining it).

3. Improvement of defense. (Brief reports from company commanders to

be followed by work being done on order of battalion commander after

inspection.)

4. Organization of watching (not sentry duty) (by company commander

under supervision of battalion commander).

5. Organization of observation (not sentry duty) (by company commander

under supervision of battalion commander).

6. Organization of supply (procuring, routing, etc., of tools,

ammunition, food, water, etc.), (by company commander under

supervision of battalion commander).

7. Organization of liaison (communication) (runners, telephone,

telegraph visual signaling, pigeons, etc., by company commander under

the supervision of battalion commander). _All telephonic communication

must be in code_.

8. Organization of supplies to include amounts to be expected daily

from the rear.

9. Knowledge of enemy must be imparted to company commanders in order

to assist them in making their dispositions.

10. Frequent reports to be made of existing conditions at the front

for information of higher commanders.

11. Lateral defense of boyaux must not be overlooked.

12. Wide turning movements are not possible. Enveloping movements are

possible only on local attacks against small portions of the hostile

line after it has been pierced. All main attacks are confined to

purely frontal attacks.

13. The most important obstacle is barbed wire entanglements.

14. Communication (liaison) between and co-ordination and co-operation

of, the different elements of a command is of the utmost importance.

15. Artillery co-operates more closely than ever with infantry. Its

reconnaissance officers accompany infantry lines in order to obtain

information. _There is a certain number of artillery observers

attached to each battalion of infantry_.

The general method of attack is to smother the defense with a torrent

of explosive shells, kept up incessantly for one or more days, and

shatter the defense so they will offer but slight resistance to the

infantry; then rush forward with the infantry and seize the positions

while the enemy is demoralized, and consolidate them before

reenforcements can be brought up.

The artillery bombardment is necessary to prepare the way for the

infantry advance. It has for its objects:

(1) To destroy the hostile artillery, wire entanglements and

infantry trenches.

(2) To produce curtains of fire and prevent bringing up

reenforcements.

_Light guns are assigned to_ EACH BATTALION OF INFANTRY, subject only

to orders of regimental and battalion commanders concerned.

Save under exceptional circumstances the light gun is always attached

to the Machine Gun Company for the attack.

The essential role of the light gun is to destroy with direct fire the

visible machine guns; they are employed separately and not grouped.

The infantry is divided into two classes: Holding troops--and

attacking or shock troops. Holding troops are those doing routine or

trench duty; shock troops are picked organizations of young and

vigorous men and are kept in camps well behind the battle front.

Holding troops are two weeks in and two weeks out of the trenches.

All specialist groups, _i.e._, Machine Gun Companies, etc., are

officered, allowing company and battalion commanders to concentrate

them, if the situation requires.

_They play the normal part in combat if they do not receive special

instructions._

Attack of a Defensive Position.

Unity of command in depth must be preserved everywhere, unless there

is an imperative reason for doing otherwise.

The front of each regiment should be divided between two or three

battalions.

_Each battalion commander having to look after a front of from 500 to

600 yards, can exercise efficient control of his command._

In preparing for an assault, seniors must take steps to organize it

and make all necessary preparations themselves, and not leave all the

responsibility with the juniors.

In the assault each unit must know its special task beforehand, and it

should be rehearsed in rear of the line of trenches. Each commander

must know the exact time he is to start and must start on time.

The first waves of men are placed at 4 or 5 pace interval. Chief of

section can command only a front of 80 to 100 paces and it is

necessary to form the section in two (2) waves. The first containing

the grenadiers and automatic riflemen, the latter in the center. The

second wave contains the riflemen and rifle grenadiers, the latter in

the center.

If the terrain is cut up by woods, villages, etc., the proportion of

grenadiers may be increased by taking them from the sections in

support and the automatic riflemen sent back to the second wave.

If the distance to cross exceeds 300 or 400 yards, the number of

automatic riflemen should be increased.

_Two or three sections are usually placed abreast on the company

front, which thus covers two to three hundred yards._

The support sections follow the leading sections of their company at

about 50 yards, marching in two lines, if possible in two lines of

squad columns at 20 yard intervals.

The first wave of the support is usually formed of the one-half

section of specialists.

The echeloning of the specialists in front is also the most favorable

formation to progress by rushes in a terrain cut up by shell holes.

The chief of section is between the two (2) waves of his section.

The captain is usually in front of the support sections.

The support sections are closely followed by a powerful line of

machine guns, which are thrown into the fight when needed to reenforce

the leading units.

"Trench Cleaners" usually march immediately after the leading sections

and may be taken from the support sections. They are armed with

pistols, knives and hand grenades.

The captain can use his section complete, or take out the specialists

and use them for a particular purpose.

The specialists carry only the weapons of their specialty and have

their loads lightened. The ordinary riflemen carry the usual packs and

equipment.

Officers no longer lead the assault, but direct it. They are equipped

with the rifle and bayonet, the same as the enlisted man.

Each unit of the first wave of the attack is given a definite

objective. Different waves must not break upon the first wave.

Fire is opened by the assaulting troops only at short ranges, the

advance being protected by a curtain of artillery fire. The advancing

line makes use of shell holes and all other available cover.

When the first section reaches its objective it is joined by the half

section of riflemen; it immediately organizes the captured ground.

Attacking From Trenches.--The commanders of brigades and battalions,

with the commander of the artillery detailed to support them, study on

the ground the artillery plan so far as it affects them. Immediately

after the advance of the infantry begins, the artillery supporting it

commences an intense bombardment with the object of forcing the enemy

to take cover. At the moment laid down in the table of artillery fire

the barrage lifts clear of the trench and the infantry rush in and

capture it. The infantry must be taught that their success depends

upon their getting within 75 yards of the barrage before it lifts, in

order that they may reach the trenches before the enemy can man them.

The secret of a successful assault is exact synchronization of the

movements of the infantry with those of the barrage.

The pace of a barrage depends, to a certain extent, on the pace of the

infantry, which varies with the condition of the ground, the length of

the advance, the number of enemy trenches to be crossed, etc. It may

be from 15 to 75 yards per minute. The pace of the barrage should be

quicker at first, and should gradually slow down as the men become

exhausted, in order to give them time to get close to the barrage and

pull themselves together for the final rush.

In an attack each unit must have sufficient driving power in itself to

carry it through to its objective and enable it to hold its ground

when it gets there. When a number of trenches have to be carried,

considerable depth will be required, and the frontage must be reduced.

A brigade usually has a front in attack of 250 to 350 yards, but this

may be increased to 1,000 or 1,200 yards.

A battalion should have a front of 250 to 350 yards. The battalion

must be organized in depth in a series of waves. Two companies are

usually put abreast in the first line and the others in the second

line. Each company in both lines attacks in column of platoons at

about 50 yards' distance, with intervals of three to five paces

between men, so there would be eight lines of waves, of two platoons

each. The 8th and 16th platoons, the two in rear forming the eighth

wave, are usually not employed in the attack, but are left behind as a

nucleus to form on in case of heavy casualties.

The front line must not be less than 200 yards from the enemy's front

line.

The leading two or three waves are likely to meet machine gun fire,

and generally move in extended order. Not more than two waves can be

accommodated in one trench. Subsequent waves will move in line or in

line of section columns in single file. Russian saps must be run out

as far as possible across "No Man's Land" to be opened up immediately

after the assault, as approach trenches. Ladders or steps are

necessary to assist the leading waves in leaving the trenches, as they

must move in lines. Provision must be made for bridges over the first

line trenches for the rear waves. In the original assault line will be

more suitable for both leading and rear waves. In later stages it is

better for the rear waves to move in small and handy columns. In the

original assault the distance between waves may be 75 to 100 yards; in

later stages they may follow each other at 50 yards.

In the original assault, zero, or the time for the assault to begin,

may be fixed for the moment at which our barrage lifts from the enemy

front trench, the infantry timing their advance so as to be close

under our barrage before it lifts. In the later stages zero must be

the moment at which our barrage commences, and this commencement will

be the signal for the infantry to leave their trenches. Each wave is

assigned its own objective. All watches must be synchronized in order

that all units may start off at the appointed time.

The first wave is composed of bombers and rifle grenade men, and

attacks the enemy's first line of trenches. It must go straight

through to its objective, following the artillery barrage as closely

as possible. The second and third waves, composed of riflemen with

bayonets and Lewis guns, re-enforce the first wave after the latter

has occupied the enemy's first line trench, and attack the second line

trench. The fourth wave takes up tools, ammunition and sand bags and

assists in consolidating the line. The fifth wave is a mopping-up

party to clear the enemy's dugouts. The sixth wave comprises

battalion headquarters and has two Lewis guns, kept for a special

purpose. The seventh and eighth waves, if used, seize and consolidate

the enemy's third line trench.

Bombing squads (1 non-commissioned officer and 8 men) are on the flank

of each attacking wave. Battalion bombers are assigned a special task.

All movements must be over the top of the ground. The pace throughout

should be a steady walk, except for the last 30 or 40 yards, when the

line should break into a steady double time, finishing up the last 10

yards with a rush.

Barrage is continued 20 or 30 minutes after the objective has been

reached.

Mopping parties must be trained with great care under selected

officers. They should always wear a distinguishing mark. They must at

once dispose of any occupants who may have emerged from their dugouts,

and picket the dugout entrances.

The ultimate unit in the assault is the platoon. It must be organized

and trained as a self-contained unit, capable of producing the

required proportion of riflemen, bombers, rifle bombers, Lewis

gunners, and carriers, all trained to work in combination.

Assaulting troops should have twelve hours of daylight in the trenches

before the assault begins, to enable them to get acquainted with the

ground and get some rest. All ranks must be given a hot meal,

including hot tea or coffee, before the assault.

Take every precaution to prevent the enemy from realizing that the

assault is about to take place. Bayonets must not be allowed to show.

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

assault 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

shellholes, 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

assaulting lines, assist 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 assault. 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 assaulting 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 assist 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

assaulting 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 assailant 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

assault, 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

constitute 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 principal 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 assaulting 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 assault 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 principal

routes to all the principal 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 assist artillery

liaison officers in getting their messages back. Liaison officers must

be exchanged by all the assaulting 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 passing 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.

(e) The communicating trenches (boyaux) should be zigzagged, wide and

deep, and should follow the low ground. The longest straight trench

should not exceed thirty paces. The angle made by each turn should be

less than 140 degrees.

(f) The fire trenches should have salients and re-entrants so as to

flank the wire entanglements. The bays are usually 27 feet long with 9

feet of traverse.

(g) There are two problems in the siting of trenches, one for those to

be constructed under fire and another for those that will be

constructed without any danger from fire. Trenches built under fire

are usually made by connecting up individual shelters made by the

front line when forced to halt. Trenches built under quiet conditions

can be laid out according to the best possible plan.

Trench Construction.

Several kinds of difficulties face the trench digger: Sand, clay,

water and bullets. In order to overcome them he must be familiar with

the general arrangement of a trench, the principles which govern its

construction and the standard trench as it has been worked out in the

present war at the cost of thousands of lives.

General Arrangement.--A position is a combination of trenches,

consisting of: The fire trench, or first line, nearest the enemy; the

cover trench, just behind the first line, where all but sentinels of

the fire trench garrison are held in dugouts or shelters; the support

trench, from 150 to 200 yards in rear of the cover trench, and the

reserve, from 800 to 1,200 yards still further to the rear.

The support trench is placed far enough from the first line to prevent

the enemy from shelling both trenches at once. By a concentration of

artillery fire and a determined advance of the hostile infantry the

first line may be captured. The support trench must be so organized

that it will then act as a line of resistance upon which the enemy's

advance will break. Lieutenant Colonel Azan of the French army says:

"As long as the support trenches are strongly held, the position is

not in the hands of the enemy."

[Illustration: Plate #16]

The reserve is usually a _strong point_, so organized that it can

maintain independent resistance for several days if necessary, should

the enemy obtain control of adjacent areas.

Where possible trenches should be on reverse slopes, with the

exception of the first line; but usually the outline of a trench is

determined in actual combat, or is a part of hostile trench converted.

Under these circumstances it cannot be arranged according to tactical

ideals.

Artillery and the automatic gun are the determining factors in trench

warfare to-day. The effect of artillery fire must be limited in its

area as far as possible, and trenches are, therefore, cut by

_traverses_, which are square blocks of earth not less than nine feet

square, left every 27 feet along the trench. They should overlap the

width of the trench by at least one yard, thereby limiting the effect

of shell burst to a single _bay_, the 27-foot length of firing trench

between two traverses. Sharp angles have the same effect as traverses,

but angles of more than 120 degrees cannot be utilized in this way.

The sides of the trench are kept as nearly perpendicular as possible,

to give the maximum protection from shell burst and the fall of high

angle projectiles. The _parados_, the bank of earth to the rear of the

trench, has been developed during the war to give protection from

flying fragments of shells exploding to the rear, and to prevent the

figure of a sentinel from being outlined through a loop-hole against

the sky. The _berm_, a ledge or shelf left between the side of the

trench and the beginning of the parados, has come into general use in

order to take the weight of the parados off the earth at the immediate

edge of the trench, and so prevent the reverse slope from caving in

easily under bombardment or heavy rain.

[Illustration: Plate #16A]

Automatic guns have made it necessary to break the line of the trench

at every opportunity, in order to secure a flanking fire for these

arms. Auto-rifles and machine guns have tremendous effectiveness only

in depth, and flanking fire gives them their greatest opportunity.

Trench Construction.--The methods of building trenches are the same

whether the work is carried on under fire or not. In an attack, upon

reaching the limit of advance, the men immediately dig themselves in,

and later connect these individual holes to make a continuous line of

trench.

Most of the digging must be done at night, and must be organized to

obtain the most work with the least confusion. There are three ways of

increasing the efficiency of the men. In the first of these, squad

shifts, the squad leader divides his men into reliefs and gives each

man a limited period of intensive work. Reliefs may be made by squads

or by individuals. The second way of increasing efficiency is to

induce competition among the man and squads, thus making the work a

game in which each soldier's interest will be aroused in the effort to

do better than the others. The third method is to assign a fixed

amount of work to each man. An average task, which all ought to

accomplish in a given time, is found by experience, and those who

finish before their time is up are relieved from further work during

that shift, and allowed to return to their shelters.

Continual care must be used to check up the tools on hand, as the men

are prone to leave them where they were working rather than carry them

back and forth to work. Each unit must guard its property from

appropriation by neighbors on its flanks.

System of Laying Out Trenches.--The trace of the trench is first

staked out, particularly at traverses and corners when the work is to

be done at night. Measurements should be exact, and the men should be

required to line the limits of each trench so as not to exceed them

in digging. All sod should be taken up carefully and used on the

parapet for concealment or on the berm to make a square back wall for

the dirt of the parapet. If possible this should be done with the

parados wall, so as to make it as inconspicuous as possible from the

front.

Men should begin to dig at the center of the trench and throw the dirt

as far out on the sides as possible, so that as they go deeper the

earth can be thrown just over the berm. The slope of the sides will be

kept steep and the men prevented from widening the trench as they dig.

In sandy soil the sides of the trench should be allowed to reach their

angle of repose (which is wider at the top than required), then the

trench walls supported with _revettments_ to the proper width, which

are filled in behind with sand. Always dig to full depth before

beginning to revet, as it is impossible to dig deeper afterwards

without loosening the revetting.

Revettments.--Every trench at points needs support, and this

_revetting_ may be done with any of the following materials: Sod;

corduroy of logs laid lengthwise; sand bags (size 20 in. x 10 in. x 5

in.); galvanized iron; chicken wire and cloth made in a frame about

six feet long; _hurdles_, wicker mats made by driving three-inch

stakes into the ground, leaving uprights as high above the ground as

the depth of the trench, then weaving withes and slender saplings

between the uprights; expanded metal; _gabions_, cylindrical baskets

made like hurdles except that the stakes are driven in a circle;

_fascines_, bundles of faggots about 10 inches in diameter by 9 feet

long. The faggots are laid together on a horse or between stakes

driven in the ground, then "choked," or bound tightly together, by a

rope 3 feet 8 inches long with loops at each end, tightened with two

stiff levers. The bundle is then bound with wire at intervals of two

feet. The circumference of a fascine should be 25 inches.

[Illustration: Plate #17]

Capt. Powell of the C.E.F. found during 18 months' service in the

trenches, that a separate construction for the bottom and firing step

from that of the parapet made repair much simpler when the trench was

damaged by shell fire. The upper part of the trench usually suffers

most, while the bottom section, if unattached, often remains intact

and the drainage system needs only to be cleared out. If the portion

above the firing step is one piece with that below, however, the whole

trench has to be reconstructed.

There is nothing more important than the supports used to keep

revetting in place. With sods, sand bags, concrete and gabions, a

proper arrangement in the first place will make other support

unnecessary.

Sod should be placed carefully, with a slope of not more than one

inch on four, with the vegetation uppermost. This type is least

affected by rain.

Sand Bags should be used like brickwork, laid in alternate headers

(binders) and stretchers. Their use should be confined as far as

possible to emergency and repair work, because after a few weeks the

bags rot and cannot be moved about. If the trench wall has been

demolished by artillery fire, the particles of cloth make digging out

the bottom of the trench a very difficult matter.

Concrete Work has been used extensively by the Germans, but the

chips fly like bullets under shell explosion, and the concrete cracks

and disintegrates in severe weather. It is used in the bottom of

trenches for drainage and for the firing step.

Gabions may be set into the wall of the trench and filled with

earth, or used at corners to prevent the wearing down of the edge,

which reduces the protective effect of the trench. Set in at a slight

angle they will hold the side without further re-enforcement.

With the other forms of revetting some secondary support is required.

This is usually furnished by sinking stakes into the bottom of the

trench and securing their upper ends to a "dead man"--a stake or log

sunk in the ground more than three feet away. The tendency is to sink

the dead men too near to the trench, and to attach too many wires to

one of them. It is important to sink the stakes at least one foot

below the bottom of the trench. By digging holes for them instead of

driving them in directly, the sides of the trench need not be

disturbed by the concussion of driving the stakes. This is especially

important in sandy soils. Stakes should be placed about two feet

apart. Dead men should be buried deeply enough to prevent cutting by

shell explosions.

Trench Armament.--A few machine guns are set in concealed

emplacements along the trench to cover important salients. The

automatic rifle is used over the parapet. Besides these there is the

rifle grenade and trench mortar. The rifle grenade has a simple

emplacement. After securing the proper elevation, the butt of the

rifle is placed between posts or blocks of wood and the muzzle rested

against a log on the wall of the trench. A trench mortar emplacement

is dug in the rear wall of the trench, or a shell hole is utilized,

care being taken to conceal it from aerial observation.

Loopholes.--Loopholes are still much in use for observation, but

they are employed less and less for firing, as they are difficult to

conceal from the enemy and almost useless when the enemy is close.

They should cut the parapet diagonally, not directly to the front, and

should be concealed by vegetation and by a curtain over the opening

when they are not in use. Sheet steel plates with small peep holes are

used on the parapet. They are set up with a slope to the rear to

deflect bullets.

Trench Bottoms.--In clay or hard soil special arrangements must be

made for drainage. Where possible the trench should have a convex

surface and should be smooth. A rough bottom means delay in reliefs,

and possible injuries. Where trenches are used for long periods

board walks should be constructed. Under these drains or sink holes

can be placed to collect water. A sink hole may be constructed by

digging a pit filled with small stones, or a barrel may be sunk into

the ground and filled with stone. Where there is not sufficient slope

to carry off the water, or at the lowest point of a drainage system, a

water hole should be dug in front of the trench large enough to handle

the drainage water.

[Illustration: Plate #18]

Communication Trench (or Boyau).--Running to the rear and joining

the different parallel resistance trenches are communication trenches

or boyaux. These are for transportation of men and material as well as

for communication. Communication trenches should be made wide enough

to allow travel for men with loads, should be at least seven feet deep

and as smooth as possible on the bottom. Rough places will delay

traffic. They are dug with turns every 20 or 30 yards to prevent their

being swept by gun fire. When boyaux are built by night sharp zig-zag

corners should be used, or the angles will not be acute and protection

will be lost. During daylight when the directions can be seen, the

construction may be a serpentine curve, with no stretch of more than

30 yards visible from one point.

Boyaux are sometimes used for lateral defence and often emplacements

for automatic guns are arranged to cover stretches of them. Bombing

stations are placed near by to protect the guns and to clear the boyau

of the enemy. At these points the boyau is left straight for a short

distance in front. Where provision is made for lateral or frontal

defence by rifle fire, firing steps are constructed. If this is

inconvenient for movement along the boyau, individual emplacements

must be made in the side wall for firing. Sentry posts are dug at

right angles to the boyau.

Arrangements for passage of men moving in opposite directions may be

made by extending short spurs at the corners, enlarging the boyau at

the bends, digging niches or passing points here and there, or

constructing island traverses with the boyau running around on each

side.

[Illustration: Plate #19]

Every boyau should be marked where it meets a trench with a sign

indicating the place and trench. Without this messengers, reliefs and

re-enforcements may easily be lost in the maze of trenches.

Latrines should be run out about 20 feet from boyaux at points

directly in rear of lateral trenches. If possible they should be

placed so that men cannot enter them without passing near the platoon

leaders. This will prevent men from leaving the front line, under the

pretense of going to latrines, during bombardments or mining

operations. The trench leading to a latrine should be constructed like

a boyau, and the pit should be close to the side nearest the enemy, to

give the best possible protection from shell fire. There are three

types of trench latrines: Deep boxes which are covered and have rough

seats; short straddle trenches or trenches equipped with a single

horizontal bar, and portable cans, used where the ground or the

limited space make it impossible to dig pits. These cans should be

emptied daily into holes behind the trenches, which are covered after

the cans are emptied into them.

Urinals should be separate from the latrines. They may be either holes

about three feet deep filled with stone, troughs with a covered pit at

the end, or portable cans.

Shelters. For the protection of men not actually on duty three forms

of shelters are used. The _splinter-proof_ is a form of light shelter

whose covering affords protection only against splinters. These are

usually on the reserve line. About 12 inches to 20 inches of earth

over a roof of logs or planks will afford protection from splinters

and shrapnel. Curved sheets of iron may also be used. The _deep

shelter_ or _bomb-proof_ is a chamber constructed by digging from the

surface and constructing a roof. To protect against eight-inch

shells the top of the chamber should be twenty feet below the surface.

Heavy beams or sections of railroad iron are laid across the roof.

Above them is a layer of earth several feet thick; then another layer

of timber extending to undisturbed ground on the sides with concrete,

crushed stone, metal, etc., above to make a percussion surface for

exploding projectiles that penetrate the upper layer of earth. This

layer fills in the rest of the space to the level of the ground.

[Illustration: Plate No. 20.]

Shelters should not exceed six feet in width, but can be of any

length. This will prevent the crushing in of the roof timber by the

explosion of a projectile buried in the upper layer of earth. The

principles of constructing shelters will be considered under

"Dugouts," as they are similar for the two types.

Dugouts are chambers tunnelled into the ground with twenty feet or

more of undisturbed earth above them. They are used in the cover

trenches and sometimes in the first line. Enough of them must be built

to shelter the garrison of each sector, allowing one man per yard of

front. They must also be built for machine gun and trench mortar

detachments.

Sentries must be stationed in observation posts which command the

ground in front of each dugout. They must be connected with the

dugouts by telephone or speaking tube.

Position.--Dugouts must always be on the side of the trench toward

the enemy. This prevents flying shells from falling into the

entrances. They should connect with lateral trenches, not with boyaux,

as men at the entrance obstruct traffic through the boyaux.

Entrances and exits must be well concealed, with not less than five

feet of head cover. This should be provided with a bursting layer. All

dugouts must have at least two openings, one on the opposite side of

the traverse or angle from the other. It is well to have an exit

behind the parados leading to a surprise position for a machine gun

and bombers. All openings must have a sill 6 inches to 8 inches high,

to prevent water from entering the dugout.

Galleries leading to dugouts should be built at an incline of 45

degrees. Their dimensions should be 2 feet 6 inches by 6 feet. Frames

are of squared timber. The sill and two side posts should be not less

than 6 inches square, and the frames in the passageways 2 feet 6

inches by 4 feet 6 inches. They must be placed at right angles to the

slope of the gallery, with distance pieces between uprights. In

treacherous soil the frames rest on sills. Steps in the passageway are

1 foot broad and 1 foot high.

Bomb-traps, extensions of the gallery about 3 feet long, should be

dug beyond the point where the entrance to the dugout chamber leads

off from the gallery. These will catch bombs thrown in from the

surface and protect the chamber from the effects of their explosion.

Interior. The standard section is 6 feet by 8 feet, to allow for

bunks on each side. Frames of 6 by 6 timber spaced 2 feet 6 inches

apart support the sides and roof. Roof planking should be 2 inches

thick, and the sides should be covered with 1-1/2 inch plank or

corrugated iron. Two shovels and two picks for emergencies should

always be kept in each dugout. The construction of the chamber should

be that of a very strong box, so that it will stand strain, if

necessary, from within as well as from without.

Depots for Supplies must be near the headquarters of the platoon,

company, battalion and regiment. Shelters may be made with ammunition

boxes set into the side of the trench. Places should be provided for

the following: Food, ammunition for rifles and auto-rifles, grenades,

rockets, tools and other supplies. Places must also be arranged in

the front line for ammunition, rockets and hand and rifle grenades.

Telephones. Communication is established as speedily as possible

with the various units. In the forward trenches wires do not last long

under bombardment and fire left open along the side of the trench,

where quick repairs can be made. All soldiers must be taught to

respect these wires and to care for them when they are found under

foot or hanging. Conduits are dug for wires to battalion and

regimental headquarters, and these are fairly safe from shell fire.

Departure Parallel. In preparing for an advance upon the enemy, a

straight line trench without traverses, and with steps at the end for

exit to the surface, is built in front of the first line trench. This

line of departure is generally brought within about 200 yards of the

hostile line by means of _saps_, short trenches run out from the front

line to the new parallel. Since this line of departure can be seen by

the enemy, it is sometimes better to construct steps in the front line

trench itself, or when possible to build a _Russian sap_. This is a

tunnel very near the ground, which can be broken through at a moment's

notice when troops are ready to advance.

Machine Gun Emplacements.--Shell-holes with a good field of fire and

emplacements along boyaux are the best location for machine guns. Few

guns are placed in the front line, and these only at strong points in

the line, which command a maximum field of effectiveness. Shell-holes

may be imitated for machine gun emplacements, but in any case they

should be connected by underground passage with the trenches. Thus

when trenches are destroyed by bombardment the machine guns remain

intact. The field of fire for each machine gun should be carefully

determined and marked by three stakes, one for the position of the

gun, the other two for the limits of the field of fire. Using these as

guides, the gun can be fired correctly at night. During the day it

is never left in place nor fired from its actual emplacement.

[Illustration: No. 21]

Listening Posts.--These stations are usually carried out to the edge

of the entanglements nearest the enemy. The listening station must be

large enough for half a squad, and often has an automatic rifle and

grenade thrower. There should be not more than two posts for each

battalion. They are not occupied during the day. They are hard to

defend and easily captured by a raiding party which cuts the wire to

one of the flanks and comes in from the rear. The boyau leading to the

post should be zig-zagged. The post itself should be deep enough for

good head cover.

Wire Entanglements.--The object of the entanglement is not to stop

completely the advance of the enemy, but to delay him at close range

under machine gun, auto rifle and rifle fire, and within range of

grenades and bombs. Entanglements should be concealed as much as

possible from the enemy's trenches and from aerial observation. If

possible, they should be placed on a reverse slope or in a dead angle.

They should be from 50 to 100 yards in front of the trench, so that

artillery fire directed upon the trench will not be effective on the

wire. At the same time the wire must not be far enough advanced so

that the enemy's raiding parties can cut the entanglements.

Wire entanglements are classified as high entanglements, low

entanglements and loose wire.

High Entanglements are strung on metal or wood posts about four feet

high, both wire and posts being painted for camouflage. The driving of

posts must be muffled, and metal screw posts are used when near the

enemy's line. Posts are placed in two parallel lines, two yards apart,

spaced alternately so that the posts in one line are opposite the

middle of the interval in the other.

Tracing Entanglements is done by a sergeant followed by two stake

placers, two holders and two drivers, who in turn are followed by men

attaching wire. Two men carry each roll of wire, and each pair (there

are twelve pairs in all) strings one wire. A panel between stakes is

composed of four strands. Each wire should be wrapped around each

post. The same arrangement of panels should run between the two lines

of posts. The entanglements are in three lines about 20 yards apart,

the nearest being 20 yards from the front line trench. The

entanglement nearest the enemy should be constructed first, so that

men always work nearest their own trenches. All wire entanglements

should be at all points commanded by the flanking fire of machine

guns. High entanglements (known as abatis) may be made by felling

trees toward the enemy, and similar entanglements made of brushwood

are useful in emergency.

Low Entanglements are formed of pickets two feet high, 2-1/2 inches

in diameter, wired in all directions. Vegetation renders the

entanglement invisible from the enemy and from aerial observation.

This type may also be placed in shallow excavations which are

concealed from the enemy and partly protected from artillery fire.

Sharpened stakes, with their points hardened by fire, driven obliquely

into the ground, may also be used.

Loose Wire in the form of loops of small diameter fastened to

stakes, or wire laid along the ground and attached at the ends, or

spirals of barbed wire in racks, is used for entanglements. It is

reported that this form is coming into considerable use, but the

details have not been published. Such entanglements are much harder to

locate by aerial observation.

* * * * *

The following are a number of criticisms made by Lieut. Henri Poire of

the French army, detailed as instructor at Plattsburg, upon the system

of field works constructed by the 17th and 18th Provisional Training

Regiments. The ground was of loose sand, with some gravel at a depth

of about six feet.

1. Dimensions of trenches as laid out were not followed.

(a) Bottom of trenches behind firing steps too narrow.

(b) Firing step too deep. It should never be more than 3 feet 4

inches below berm of parapet.

(c) Parapet much too thin in most cases. It should be at least

three feet thick.

(d) Communication trenches (boyaux) generally too narrow.

(e) Islands in communication trenches should never be less than

10 x 12 yards--otherwise one shell will demolish the entire

passageway.

2. Revettment work not well anchored. In some cases too many wires

from supports fastened to one dead man. Another fault is that dead

men were not buried deeply enough in the ground, nor far enough back

from the trench. In one case a dead man (a stake) supported all four

sides of an island in a communication trench. The destruction of this

post would have completely blocked every passage around the island.

Furthermore, dead men rot quickly and tend to break off. It is

necessary, therefore, to have a number of them, each holding only a

portion of the weight. All projecting branches and irregularities

along a trench should be removed by occupying troops.

3. Too many loop-holes. Except for snipers, riflemen and automatic

riflemen fire over the parapet.

4. Machine gun loop-holes not wide enough. They should not be less

than 36 inches wide. There must be vegetation planted in front and a

curtain hung over the loop-holes to prevent detection. The growing

plants in front will be easily swept away at the first discharge.

5. Remember never to imitate shell-holes until after a real

bombardment by the enemy.

6. The dugouts made were never deep enough and afforded no

protection. In fact it would be far better to have none than to be

caught inside when a shell exploded in a shallow one, because the

confinement of the explosion would intensify the effect.

7. Shelters were all too wide. Six feet is the maximum.

The platoon headquarters dugout should be of the same width as the

trench, not over three feet, but as long as necessary. Company

headquarters is six feet wide and of whatever depth required.

8. In digging, not enough care was used to conceal the fresh earth

from the enemy. Make false emplacements to utilize this dirt; also dig

dummy trenches about one foot deep, leaving the sides sharp so that

they will show clearly on aerial photographs.

9. In using plants as camouflage, distinct care must be exercised

not to put growing plants too freely nor to place them where they

never existed. The actual ground conditions must be copied.

10. Some latrines were not arranged with the stools close beneath

the wall nearest the enemy. This caused the loss of protection, which

it is imperative to consider, as many casualties occur here.

11. Too many listening posts. They are easily captured by hostile

fighting patrols. There should never be more than two listening posts

to a battalion.

12. The observation stations in many instances had no good field of

fire or were outlined against the sky on the crest of some rise. The

site for an observation post should always be placed over the crest

and have a good field of fire for use in case of attack.

Occupation.

I. Relief in the Trenches.

A. THE TWO MAIN CLASSES OF RELIEF:

1. General Relief. Applied to the relief of a whole position

manned by a division or more. Executed when large units are

going to "full rest" in the rear or being removed from one

part of the front to another. Executed in the same way as

interior relief; i.e., by successive relief of the

battalions involved.

2. Interior Relief. Applied to the relief of one sector or

portion of a sector manned by a brigade or less.

B. GENERAL PRINCIPLES OF RELIEF:

1. Interior relief is executed about once every six days; more

frequently when the stay in the trenches is particularly

arduous, less frequently when it is unusually comfortable.

2. The battalion is the relieving unit.

3. It is advisable to arrange the relief between units which

have friendly relations to one another; e.g., battalions of

the same regiment; and, so far as possible, to assign each

unit to the same trenches on each relief. This promotes

continuity of effort.

4. Relief is executed at night; the hour must be varied; secrecy

is imperative.

5. Prompt execution is essential, to prevent fatigue of the

troops and congestion of the boyaux.

C. THE MECHANISM OF RELIEF:

1. Reconnaissance, 24 hours in advance, by the captain of each

relieving company, accompanied by his platoon leaders and

non-commissioned officers. He ascertains:

(1) The plan of occupation; i.e., the dispositions and

duties of the unit to be relieved.

(2) The shelter accommodations.

(3) Work being done and proposed.

(4) Condition of the wire and other defences.

(5) The available water supply.

(6) Artillery support.

(7) Communications.

(8) The location, amount and condition of stores.

(9) Danger points.

(10) All available information of the enemy; his habits,

location of his snipers, what work he is doing.

(11) The ways and means of liaison, both lateral and from

front to rear.

To the success of this reconnaissance, the closest

co-operation between all officers of the companies

relieving and relieved, is indispensable.

2. The march from billets to the trenches:

(a) Transportation, by auto-trucks and wagons, is utilized

to a point as near the lines as possible, to carry the

packs of the men, the auto rifles, extra ammunition and

other heavy equipment. When the distance is great the

men themselves should be carried by auto-truck; this

saves time and fatigue. The men will carry rifles loaded

and locked, full cartridge belts, gas masks, and all

other lighter equipment, with rations for 24 hours at

least. Grenades will be secured in the trenches.

Electric torches will be carried by company and platoon

commanders.

(b) The strictest discipline must be maintained. On arrival

within sight of the enemy, noise and smoking (or other

lights) will be prohibited.

(c) Guides, from the company to be relieved, will meet the

relieving company promptly at a point definitely agreed

upon in advance.

3. The march through the boyaux (communicating trenches):

(a) Distance; often as much three or four miles.

(b) Order of march: company in single file, captain at the

head; each platoon leader at the head of his platoon; a

non-commissioned officer at rear of each platoon.

(c) The column must be kept closed up. Each man must consider

himself a connecting file, guiding on the head, and

behave accordingly. A guide should accompany the

commander of the last platoon.

(d) Rate of march: roughly, about 40 yards per minute. It

takes 250 men about 20 minutes to pass a given point.

(e) Route and right of way:

The first line and support trenches will never be used

as roads. Separate boyaux should, if possible, be

assigned to the troops relieving and relieved. In no

case will one company cross the path of another. In case

of two columns meeting, one moving forward, the other to

the rear, the former has the right of way.

4. No man of the unit in occupation will leave his post until

he has actually been relieved and has transmitted all orders

and information relative to that post.

5. Liaison must be established, immediately on arrival, with the

units on the flanks and with headquarters in the rear.

Captains must make sure that their runners are thoroughly

acquainted with the routes of communication.

6. As soon as relief is accomplished both captains will report

that fact to their respective commanders.

7. The relieving commander then inspects his trenches. He

ascertains that all his watchers are at their posts and that

the balance of his men know their posts and duties and are

prepared to assume them quickly.

8. The duties of the relieved commander are:

(1) To turn over his sector thoroughly policed and in good

condition as regards its construction and the new work,

if any, in progress.

(2) To turn over his supplies in good condition and fully

accounted for.

(3) After reporting the relief, to march his men back to

billets as promptly and secretly as possible, in column

of files, platoon leaders in the rear of their platoons,

a non-commissioned officer and guide at the head of each.

(4) On the evening preceding relief, to send his cooks back

to billets so that his men may be provided with a hot

meal immediately on arrival.

D. If an attack occurs during the march through the boyaux, to or

from relief, the company affected occupies the nearest

defensive position and at once notifies its battalion

commander. If an attack occurs during the actual process of

relief, the senior officer present takes command.

II. The Stay in the Trenches.

A. THE FOUR OBJECTS OF A TRENCH COMMANDER:

1. Security of his sector.

2. Protection of his troops.

3. Constant and accurate observation.

4. A continuous offensive.

B. HIS PLAN OF DEFENSE:

1. General principles of defense:

(a) Arrangement in depth. The most dependable defense is in

prearranged counter attacks. The system of defense must

react like a helical spring.

(b) Tenacity of defense.

1. Each unit must be prepared to hold its post to the last

extremity.

2. Orders to withdraw will never be obeyed unless

unmistakably valid.

3. All ground lost must be retaken at once in counter attack

by the unit which lost it.

(c) Apportionment of responsibility. Each active segment must

have a commander responsible for its defense, upkeep and

sanitation, and the discipline and instruction of his men.

2. Basis:

(a) The plan of defense turned over by the preceding commander.

This will usually suffice for the first 24 hours after

relief.

(b) General information of the enemy's lines, dispositions, and

intentions, based chiefly on aerial photographs.

C. ORGANIZATION OF DEFENSE:

1. Allocation of front. (The front of an American battalion will

average about 1,000 yards.)

Diagrams: A. The Regiment. B. The Battalion. C. The Company. D.

The Platoon.

2. Distribution of effectives. Determined chiefly by the terrain

and by 3.

3. Employment of the several arms:

(a) Machine guns. Crew of 8 men per gun. (Furnished by

detachments of a machine gun company.) Located by the

infantry commander, in concealed emplacements behind the

first line, to deliver successive barrages from flanking

positions. Effective range: up to 700 yards.

(b) Automatic rifles. Crew of 3 men per rifle. Usually posted to

enfilade the entanglements of the first line. They

concentrate the fire effect of from 7 to 10 riflemen.

Effective range: up to 300 yards.

(c) Rifle Grenadiers. Located near enough to first line to hold

the enemy trenches under fire and deliver effective barrages

near the mouths of our own communicating trenches. Should be

located near observation posts so that their fire can be

promptly corrected.

(d) Trench mortars. Located similarly to (c). Manned by

riflemen.

(e) Bombers. One supply man to each 2 grenadiers. Used for

protection of auto-rifles, in counter attacks, for

protection of communicating trenches and fighting in close

quarters.

(f) Riflemen. Posted to deliver frontal fire. Grouped according

to the plan of counter attacks.

(g) As many men as possible should be instructed in the use of

the enemy's weapons.

D. LIAISON:

(a) By telephone. Quickest and most accurate. Maintained

between each platoon and its company headquarters, and

between adjoining companies. Especially subject to

destruction in bombardment. Wireless and ground telegraphy

are used only between brigade and division headquarters.

(b) By runners ("liaison agents"). Five detailed from each

company to battalion headquarters; one sent to each

adjoining company headquarters; one from each platoon to

company headquarters; four or five on duty at each platoon

headquarters; five from each machine gun company to

battalion headquarters. Messages sent by them should, if

practicable, be written and signed, and should be receipted

for by the addressee.

(c) By rockets and flares. Quickest means of liaison with the

artillery in rear.

(d) Domestic (message carrying) grenades.

(e) Dogs and carrier pigeons. Sent out to the rear from

battalion headquarters.

(f) One searchlight--with a radius of 3 miles--is furnished to

each company.

(g) Noise. Klaxon signals, etc., give warning of gas attacks.

E. OBSERVATION:

(a) Observers:

1. Must be men of infinite patience, keen hearing and

eyesight.

2. They are located behind the first line in positions

combining good view with concealment.

3. Each is provided with a panoramic map, made from

aeroplane photographs, of the enemy's trenches. On this

must be promptly noted every slightest change in the

trace, height of parapet, etc., of the enemy's line. Such

notes greatly assist in locating machine gun

emplacements.

4. Each observer will also record in a note book everything

of importance, with the time observed.

5. A report of changes, with an abstract of observer's

notes, is forwarded daily to regimental headquarters.

(b) Watchers (sentinels):

1. Stationed, one near the door of each dugout, in the

first line, support and intermediate trenches.

2. They must be carefully concealed.

3. They must watch over the parapet (never through slits or

loopholes) so as to have unrestricted view.

4. They are furnished with signal rockets and flares for

prompt communication with the artillery, and have

authority to use them.

5. Double sentinels are posted at night.

(c) Listening Posts:

1. Located, usually in shell holes, just inside the

entanglements. Connected with front line by tunnels.

Protected from grenades by heavy gratings, when

possible, and by concealment.

2. Occupied by 4 men (1 in command), in 3 reliefs. Usually

occupied only at night unless our trenches are on a

reverse slope.

3. Chief function is protection of the entanglements.

(d) Microphone Posts.--Installed usually behind the first line.

Intercept the enemy's telephone and ground-telegraph

messages and any loud conversation in his trenches.

(e) Fixed Patrols.--Generally remain in shell holes in front of

our entanglements.

(f) Reconnoitering Patrols:

1. Composed of from 3 to 5 men, commanded by a

non-commissioned officer. Sent out at night only.

2. The company commander must promptly notify commanders of

adjoining companies of the dispatch of these patrols,

their time of departure, route and probable time of

return.

3. Men should be assigned to this duty by roster.

F. TRENCH WORK:

1. Constant battle with the elements, care for drainage,

revettment, sanitation and storage.

2. Repair of the effects of bombardment.

3. New work, for better security, communication and observation.

4. Work in the open.

(a) Usually consists of repair or rearrangement of wire

entanglements, digging new listening posts, etc.

(b) Effected by parties detailed by roster.

(c) They are guarded by fighting patrols, composed like

reconnaissance patrols. Their best protection is in silence

and concealment.

(d) Adjoining companies must be notified of their dispatch,

location and probable time of return.

(e) This work, like all operations conducted outside the

protection of the trenches, offers a valuable tonic to the

morale.

G. OFFENSIVE OPERATIONS:

1. Sniping:

(a) Snipers constitute one of the most dependable and

productive agencies of attrition.

(b) The best shots of the company are especially trained and

assigned for this duty exclusively.

(c) They operate in pairs and post themselves to cover any

exposed portions of the enemy's trenches, especially his

communicating trenches.

(d) They should be well supplied with all necessary special

equipment; _e.g._, sniperscopes, telescopic sights, painted

headgear, etc.

2. Mining Operations.

3. Raiding:

(a) Object of raids: destruction of the enemy's defenses,

disturbance of his morale, collection of prisoners and

information.

(b) The personnel of raiding parties will usually include: A

commander and second in command, bayonet men, bombers,

engineers, signal men, stretcher bearers. Their numbers and

proportions are regulated by the nature and difficulty of

the task.

(c) Co-ordination with the artillery barrage is the essential of

their success. The limit of advance, extent of operations,

and time of return will therefore be set in advance and

rigidly adhered to.

H. ROLE OF THE TRENCH COMMANDER:

1. Inspections: The men will be formally inspected twice daily at

the general "stand to" by the company commander. Particular

attention will be paid to the health of the men, condition of

their feet and their clothing. Each man must have at least one

pair of dry socks always available. Arms, gas masks, and other

equipments will also be rigidly inspected.

2. Roster: The company commander will carefully supervise the

preparation of the duty roster. An obviously equal distribution

of the arduous duties involved in trench life is essential to

the maintenance of morale.

3. Reports and Records: (Additional to those already required by

regulations.) Log Book, Report of Casualties, Wind Report

(daily), Bombardment Report (daily), Intelligence Report, which

will include observer's notes and changes (twice daily), and a

daily report of Work completed and Undertaken.

4. "One principle which the trench commander should never forget is

the necessity for his frequent presence in the midst of his men.

* * * Direct contact with the troops on as many occasions as

possible is the most certain way to gain their confidence."

[Illustration]

[Illustration]

Duties of the Company Commander.

1. To inspect the sector his company is to occupy, one day in

advance of occupying it.

2. To assign segments to the platoons.

3. To prepare a plan of defense.

4. To connect by liaison with the companies on his flanks.

5. To have an agent or runner at Battalion Headquarters.

6. To prepare a plan for counter attacks.

7. To report to the Battalion Commander when his company has taken

up its position:

(a) Its situation.

(b) Security.

(c) Liaison.

(d) State of position left by predecessor.

(e) Defense of sector.

(f) Plan of counter attacks.

8. To inspect the trenches frequently to see that everything is in

proper condition and that his men are in jubilant spirits.

9. To have platoon guides report to Battalion Headquarters on the

date for the relief of his company and act as guides to the

company that relieves him.

10. To keep a special log book in which the following are kept:

(a) Work completed by his unit.

(b) Work under way.

(c) Work proposed.

11. Turn over to his successor:

(a) Measures taken for security.

(b) Plan of attacks.

(c) Plan of counterattacks.

12. Have one officer on duty at all times.

13. "Stand to" will take place one (1) hour before daylight, and all

available men will attend. There will be a thorough inspection.

Rapid loading will be practiced. The firing position of every

man will be tested to see if he can hit the bottom of our wire.

Gas helmets will be inspected.

14. Time table--allot hours of work, rest and meals.

15. Supplies--make timely requisitions for them--be especially

watchful about meals and rations--have no delays.

16. To have one watcher and one relief on duty near Company

Headquarters at all times.

17. To get a good field of fire to the front and cover the sectors

of each company on flanks.

18. (Subject to change) Red Rocket-Artillery Barrage wanted.

White Rocket Gas Attack.

19. To report twice daily all changes in wind direction.

20. To report to Battalion Commander when relieved.

Duties of Platoon Leaders as Officers on Duty with Company.

1. Report with old officer at company headquarters.

2. Make frequent inspections of all trenches occupied by company.

3. Visit each Listening Post; at least once during tour of duty.

4. Visit all sentinels and receive their reports.

5. See that one non-commissioned officer per platoon is on duty.

6. Receive reports of non-commissioned officers after they have

posted sentinels.

7. At end of tour hand over to new officer all orders, a report of

work in progress, and any useful information.

8. Report with new officer at Company Headquarters on completion of

tour.

9. To report anything unusual to Company Headquarters.

10. To send dead and wounded to dressing station trenches.

11. To send patrols to front at night.

Duties of Platoon Leaders.

1. Must accompany company commander on inspection of trenches one

day previous to occupying them.

2. Make necessary reliefs for his men in his segment.

3. Make a plan of defense and counterattack for his position or

approve the one left there.

4. Establish sniping posts and arrange reliefs.

5. Establish Listening Posts and arrange reliefs.

6. Assign non-commissioned officer to duty with platoon and arrange

relief.

7. Instruct every man as to his place in case of attack.

8. Establish liaison with platoons on both flanks; and one runner

to Company Headquarters.

9. Have one platoon guide report to Company Headquarters on day his

platoon is to be relieved.

10. On completion of posting his platoon, report to his company

commander.

11. Turn over to platoon relieving him all orders and data

pertaining to his position.

12. Be especially attentive to rigid military discipline; _i.e._,

every soldier to be neat; equipment must be clean at all times;

to render the required salute when not observing or firing at

the enemy.

13. Have one non-commissioned officer on duty at all times.

14. To inspect rifles, equipment and latrines twice daily.

(a) To have at least one latrine in working order at all times.

(b) To have a sentry on duty at each platoon dugout at all

times.

(c) Establish one Observation Post in daytime.

15. In Front Line Trenches:

(a) No smoking or talking to be allowed at night.

(b) Every man to wear his equipment except packs.

(c) Have rifle within reaching distance.

(d) All reliefs to be within kicking distance of soldier on

duty.

16. Inspect at "Stand to" and report results to Company

Headquarters, especially if each man has 170 rounds of

ammunition and necessary grenades and bombs.

17. To be especially attentive to sanitation and care of the men's

feet.

18. To have one (1) watcher and relief on duty at all times near

platoon dugouts.

19. To get a good field of fire to his front and to cover the sector

of each platoon on his flanks.

20. Make requisition for material.

21. To see that all of his men are properly fed.

22. Report to company commander when relieved.

23. Must know what every man is doing at all times.

Duties of Non-Commissioned Officer on Duty (Each Platoon).

1. To make frequent inspections of the position occupied by his

platoon.

2. To be responsible that each soldier knows his duties.

3. To report anything of special importance to officer on duty.

4. On being relieved to report with the new non-commissioned

officer to the officer on duty.

5. After posting sentinels to report "All is Well" to officer on

duty.

6. Explain to his sentinel his duties, the position of Section and

Platoon Commanders and of sentries on either side; and to

caution his sentries when friendly patrols are out, the probable

time and place of return.

7. Bayonets will always be fixed in front line trenches.

8. At night time to have double sentinel.

9. To see that each sentinel in daytime has a periscope.

10. Rifles to be loaded; no cartridge shall be in the chamber

except when necessary to shoot.

11. To report to Company Headquarters any change in direction of

wind.

Patrols.

1. Usual orders about patrols.

2. Always go out at night via the Listening Post; tell the men in

the Listening Post your mission and probable time of return.

Sentinels.

1. To sound Klaxon horn on approach of gas attack.

2. To report immediately to non-commissioned officer on duty any

change in direction of wind.

3. In cold weather to work bolt frequently to keep it from

freezing.

4. At night to challenge only in case of necessity, and then only

in a low tone. Challenge "_Hands up._"

5. Number of posts depends on assumed nearness of enemy and local

conditions. Normally one per platoon by day and three double

sentinels per platoon at night.

6. Relief kept close at hand. Report "All is Well," or otherwise,

when officer passes.

7. Screened from observation.

8. Remain standing unless height of parapet renders this

impossible.

Machine Guns.

1. Non-commissioned officer and one (1) watcher on duty at all

times.

2. Except in emergency they will not be fired from their regular

emplacements.

3. Unless emplacements are well concealed, guns will not be mounted

except between evening and morning "stand to."

4. Before dusk each gun will be sighted on some particular spot

either in front of or behind the enemy's line.

5. Range cards will be prepared and kept with each gun.

Snipers.

1. Sniping Post consists of one (1) observer and one (1) rifleman

with relief of two (2) men posted close by.

2. Sniping post should be well concealed.

3. Daily report from each post, of

(a) Any work done by enemy.

(b) Enemy seen; place, uniform, apparent age, physique,

equipment.

(c) Any other information of interest.

4. Sniper to be appointed from each section.

5. Must be intelligent, alert, good scout, good shot, courageous.

6. Snipers should spend 24 hours in trenches with those of command

which theirs is to relieve, before relief takes place.

7. No night work required of these men since they must be

constantly on the alert during the day.

Organization of a Platoon--Rifle Company--Table No. 7

PLATOON

Platoon Headquarters

1 Lieut.

1 Sgt.

4 Privates.

1st Section | 2d Section | 3d Section | 4th Section

Hand Bombers |Rifle Grenadiers| Riflemen | Auto-Riflemen

----------------+----------------+-------------------+--------------------

3 Teams, each | 1 Team of | 1 Sgt. | 1 Sgt. and 2 Corps.

1 Leader | 6 Grenadiers | 2 Squads of | 4 Teams, each

1 Thrower | 3 Carriers | 8 men each | 1 Gunner

1 Carrier | (May be | 4 Extra | 2 Carriers

1 Scout | subdivided) | riflemen[R] |

2 Corps. | 2 Corps. | 1 Sgt. and 2 Cpl. | 1 Sgt. and 2 Cpls.

4 Pvts. 1st Cl. | 1 Pvt. 1st Cl. | 6 Pvts. 1st Cl. | 4 Pvts. 1st Cl.

6 Pvts. | 6 Pvts. | 12 Pvts. | 8 Pvts.

Total--12 | Total--9 | Total--21 | Total--15

[Footnote R: Runners: Attached to 3d Section and 7th Squad. With

Platoon commander when company is in extended order formation.]

_Suggested Organization of Platoon in Close Order and for

Administration._

1st Squad | 2d Squad | 3d Squad | 4th Squad |

---------------+-----------------+-----------------+----------------|

Bomber Section | 1/2 Auto Rifle | 1/2 Auto Rifle | |

(less 1 bomber | Section i.e., | Section i.e., | Grenadier |

team) | Cpl and 2 teams | Cpl and 2 teams | Section |

| | | |

1 Corp | 1 Cpl. | 1 Cpl. | 1 Cpl. |

7 Pvts. | 6 Pvts. | 6 Pvts. | 7 Pvts. |

| | | (Extra Cpl. in |

| | | File Closers) |

---------------+-----------------+-----------------+----------------+

5th Squad | 6th Squad | 7th Squad |

---------------+-----------------+-----------------|

1 Rifle Squad | 1 Rifle Squad | 1 Bomber Team |

| | plus 4 extra |

| | riflemen[S] |

| | |

1 Cpl. | 1 Cpl. | 1 Cpl. |

7 Pvts. | 7 Pvts. | 7 Pvts. |

| | |

| | |

---------------+-----------------+-----------------+

Right Guide--Automatic Gun Sgt. Left Guide--Rifle Sgt.

Chief of Platoon--Lieut. File closer or acting 1st Sgt.--Sgt.-Asst.

Note.--If desirable the 4 mechanics and 4 privates (signalmen) who are

not assigned to platoons regularly, can be used to fill the blank

files in the 2d and 3d squads.

[Footnote S: Runners: Attached to 3d Section and 7th Squad. With

Platoon commander when company is in extended order formation.]

Deployments.

GENERAL PRINCIPLES:

(a) The following plans for deployment are not to be regarded as

rigid. The positions of the various squads depends upon tactical

considerations.

(b) The platoon in attack will be used only for accomplishment of

its offensive mission. Moppers-up, additional carriers, etc., will be

furnished by other organizations.

A. Being in line, to form single skirmish line to the front.

1. As skirmishers (so many) paces, guide right (left or

center). 2. March.

Executed as described in pars. 206 and 208, i.d.r.

Normal interval to be ordered, 4 or 5 paces.

This formation to be regarded as exceptional.

B. Being in column of squads, to form single skirmish line. Same

command as in (A). Executed as described in para 207 and 208,

i.d.r.

C. Being in line to form double skirmish line to the front (_i.e._,

to take the "Formation for Attack" in the diagram.)

1. In two lines. 2. As skirmishers (so many) paces, guide right

(left or center). 3 March.

Executed according to the principles in pars. 206 and 208,

i.d.r., except that at the command March the even-numbered

squads stand fast while the odd-numbered squads form the

first line by deploying on the base squad as in the case of

deployment in single line. Similarly, the even-numbered

squads form the second line by deploying on their base squad

after the odd-numbered squads have moved forward about 20

paces.

[Illustration: NORMAL BATTALION FORMATION IN ATTACK]

D. Being in line or column of squads to deploy in line of squad

columns in one or two lines. Use same commands and execute in

same manner as described in (A), (B), (C), except that in the

command "Squad Columns" is substituted for "as skirmishers,"

and in the execution each corporal on approaching the line

forms his squad in "squad column" instead of deploying it as

skirmishers.

_E.G._ 1. In two lines--2. Squad columns (so many) paces, Guide

right (left or center)--3. March.

This gives a "Formation of Approach" as the French describe it,

or as an "Artillery Formation" as the British describe it; which

may be used directly or indirectly (by means of echelons) for

advancing when not liable to infantry fire.

[Illustration: Plate #22]

E. Being in above formation to vary the intervals.

1. Squad columns (so many) paces, 2. Guide right (left or

center). Executed in the same manner as similar movement

described in i.d.r. 126.

General Principles of the Platoon Formation in the Assault of

Fortified Positions in Trenches. (Points of Resistance, Etc.).

1. The platoon is now a complete fighting unit within itself. It

contains riflemen, bombers, auto-riflemen, and rifle grenadiers. With

this combination the platoon commander has, under his immediate

control, all the different kinds of fire available to the infantry.

[Illustration: Plate #23]

2. This formation was developed so that the platoon commander could

meet the different contingencies that arise from being opposed by

points of resistance in a "Trench-to-Trench" attack or the

"Semi-Open-Warfare;" that is the secondary stage of a push.

3. When strong opposition develops, the principle on which the platoon

works is to develop or surround the point of resistance, the platoon

acting either alone or in conjunction with neighboring platoons. The

four different kinds of fire are then used to their best advantages to

silence or diminish the enemy fire thus making this manoeuvre

possible.

4. In order to obtain success it is first necessary to impress on the

officers and men that the primary advantage of the entire formation is

its mobility, and the scope it gives to the initiative of the platoon

section, squad and team leaders. In studying this formation it is

first necessary to free the mind of all parade ground formations and

to feel that there is nothing to hinder any desired movement of the

sections, so long as the movement is not contrary to the operation

orders for the attack. Until this idea is grasped thoroughly no

progress can be made.

5. There is no typical or "normal formation." The one given at the

beginning of this instruction here is a drill or parade ground

formation, and while it may be used under actual conditions of

warfare, it is simply utilized at this time as a basis from which the

necessary variations may be worked out. In an attack, every platoon in

the battalion may use a different formation.

6. The formation to be used is decided upon after a careful study of

air-photographs. As far as possible all points of resistance are

picked out and the best method of meeting the situations that may

arise are then considered. The platoon is then arranged so as to best

facilitate this manoeuvre. It must be realized that there will be

other platoons on the flanks and in the rear, and their dispositions

must be studied with a view of their probable bearing on the points of

resistance.

7. In order to know how to get results it is first necessary to have a

very clear conception of the uses and limitations of the different

weapons in the platoon.

Briefly they can be used in the following ways:

(a) The auto-rifles open up a point blank fire on the strong point as

soon as it is discovered. Their function is to either draw the fire of

the enemy or to silence him by a hit or forcing him to take cover.

Their work may be compared to the work of the field artillery in a

barrage. They cover the movement of the infantry across the open. The

auto rifles so place themselves at such points that their line of fire

will in no way interfere with the manoeuvre of the commander of the

platoon or the remaining units of the platoon interfere with the

effective use of the auto rifles of the platoon.

(b) The rifle grenadiers advance at once just as close as possible,

but at all costs to within effective grenade range. They then take

cover in shell holes, trenches, etc., and open up a rapid fire. They

are the long distance howitzers of the platoon and are very valuable.

By a well placed grenade the whole resistance may be overcome. This

section usually works around a flank.

(c) The riflemen work up by squad as far as practicable and to a

flank, when an opportunity presents itself, the squad opens fire in

such a manner as to protect advance of other squads or teams.

(d) The bombers endeavor to get well around behind the enemy and

taking advantage of cover get to within bomb range. They may be

compared to the close range howitzers or trench mortars.

When all four sections are in action at proper ranges, the opposition

can probably last but a short time, and as soon as the machine guns

cease fire the platoon, especially the riflemen, go after the

remainder of the garrison with the bayonet.

[Illustration: Plate #27]

It may happen that the barrage put up will so demoralize the enemy

that the riflemen can advance before his machine guns are even put out

of action. This operation allows the rifle men to get in with the

bayonet, if the resistance is not sooner overcome.

When the different sections are getting to their places, they usually

find enough shell holes or old trenches to obtain cover. They should

not move as entire sections, but as small groups of three or four at a

time.

8. After the encircling movement has once begun, the platoon commander

loses all control, and the action is then conducted by the section,

squad or team leaders. They must be trained to act on their own

initiative, as further orders are rarely practicable.

The resistance will finally be overcome, either because the enemy will

retreat or surrender under the menace of encirclement, or by the

losses caused by our fire or by the attack at close range of our

bombers or else by the final assault with the bayonet led by our

riflemen.

It must be remembered that under an artillery barrage it is never

possible to issue verbal orders, so the sections must be trained to

understand and obey the arm signals of its officer, or more often to

work without orders.

9. A sequence of command must be arranged in each section, squad and

team down to the last man.

REMARKS REGARDING THE FORMING OF WAVE FROM CLOSE ORDER.

The sketch of deployment attached is an illustration of one of the

formations that may be adopted. It is given as an example. Any other

wave formation may be practically as easily formed up. The platoon

commander simply calls out the squads he wants in the first line.

_It must not be imagined that this transition from close order to

extended is done in the field when actually under fire or as a result

of surprise._

Before the platoon goes into an attack it is all arranged so as to

allow it to be changed with ease from column of sections at extended

intervals (formation for approach) to the wave formation decided upon.

This arrangement is made when the platoon is miles to the rear.

When the change is made from column of sections to the wave formation

there must be no crossing of sections as they go to their places.

Some of the Many Questions a Platoon Commander Should Ask Himself on

Taking Over a Trench, and at Frequent Intervals Afterwards.

1. _I am here for two purposes: To hold this line under all

circumstances, and to do as much damage as possible to the enemy? Am I

doing all I can to make this line as strong as possible? Am I as_

OFFENSIVE _as I might be with organized snipers, sniperscopes, rifle

grenades, catapults, etc., and patrols?_

2. Do I connect up all right with the platoons on my right and left?

Do I know the position of my nearest support?

3. Does every man know his firing position and can he fire from it,

over the parapet, at the foot of the wire?

4. Where are my S.A.A. and bomb stores? Are they under cover from the

weather?

5. Do all my men know their duties in case of attack--bombers

especially?

6. Are all my rifles and ammunition clean and in good order? Have all

the men got rifle covers? Are the magazines kept charged?

7. Is my wire strong enough?

8. Are my parapets and traverses bullet-proof everywhere?

9. Where are my sally ports?

10. Where are my listening posts? Are my listening patrols properly

detailed?

11. What points in front particularly require patrolling at night?

12. Are my sentries in their right places? Are they properly posted by

N.C.O's.? Have they received proper instructions?

13. Have I got the S.O.S. message in my pocket, and do I know the

orders regarding its use?

14. Are the trenches as clean and as sanitary as they might be? Are

live rounds and cases properly collected? Are my bags for refuse and

empties in position?

15. Are my trenches as dry as I might make them?

16. Am I doing all I can to prevent my men getting "Trench Feet"?

17. How can I prevent my parapets and dugouts from falling in?

18. Have I got at least one loophole, from which men can snipe, for

every section? Have I pointed out to Section Commanders the portion of

the enemy's trench they are responsible for keeping under fire, and

where his loopholes are?

19. Have my men always got their smoke helmets on and are they in good

order?

20. Are the arrangements, in case of gas attack, complete and known to

all ranks?

21. Are the orders as to wearing equipment carried out?

22. Are my men using wood from the defences as firewood?

23. Are my men drinking water from any but authorized sources?

24. _I am here for two purposes: To hold this line under all

circumstances, and I do as much damage as possible to the enemy? Am I

doing all I can to make this line as strong as possible? Am I as_

OFFENSIVE _as I might be with organized snipers, sniperscopes, rifle

grenades, catapults, etc., and patrols?_

Defensive Measure Against Gas Attacks.

I. Introduction.

A. General Considerations:

In the absence of suitable means of protection the poison gases used

in war are extremely deadly and the breathing of only very small

quantities of them may cause death or serious injury. This being the

case, it is essential that not the slightest time should be lost in

putting on the anti-gas device on the gas alarm being given.

It cannot be too strongly insisted on that the measures to meet

hostile gas attacks afford _perfect protection_, and if they are

carried out properly no one will suffer from gas poisoning.

The whole basis of protecting troops against gas lies (a) in keeping

the appliances in perfect working order; (b) in learning to adjust

them rapidly under all conditions, and (c) in ensuring that every man

is given immediate warning. These results can only be attained:

(1) By frequent and thorough inspection of all protective

appliances.

(2) By thorough instruction and training in their use.

(3) By every man understanding and complying with all standing

orders on the subject of defense against gas.

If these are effectually carried out, there is nothing to fear from

hostile gas attacks. Officers must impress this on their men, as an

important object of all anti-gas instruction should be to inspire

complete confidence in the efficacy of the methods which are adopted.

B. Nature of Gas Attacks:

(1) GAS CLOUDS:

This method of making a gas attack is entirely dependent on the

direction of the wind. The gas is carried up to the trenches

compressed in steel cylinders. These are dug in at the bottom of the

trench and connected with pipes leading out over the parapet. When the

valves of the cylinders are opened, the gas escapes with a hissing

sound, which, on a still night, can frequently be heard at a

considerable distance. It mixes with the air and is carried by the

wind towards the opposing trenches, spreading out as it goes forward.

A continuous wave of gas and air is thus formed, the color of which

may vary:

(a) Because of the weather conditions. In very dry air it may be

almost transparent and slightly greenish in color, while in

damp weather it forms a white cloud.

(b) Because it may be mixed with smoke of any color.

A cloud attack can only take place when there is a steady but not too

strong wind blowing from the enemy's lines towards our own. A wind

between 4 and 8 miles an hour is the most likely condition. An 8-mile

wind will carry the gas cloud twice as quickly as a man walks rapidly.

Gas attacks may occur at any time of the day, but are most likely to

be made during the night or in the early morning.

Gentle rain is without appreciable effect on a gas attack, but strong

rain washes down the gas. Fogs have hardly any effect and may, in

fact, be taken advantage of to make an attack unexpectedly. Water

courses and ponds are no obstruction to a gas cloud.

The gas used by the enemy is generally a mixture of chlorine and

phosgene, both of which are strongly asphyxiating. The gases are

heavier than air, and therefore, tend to flow along the ground and

into trenches, shelters, craters and hollows. The gas cloud may flow

round slight eminences, thus leaving patches of country which remain

free from gas.

Chlorine and phosgene strongly attack the mucous membranes of the

respiratory organs, causing bad coughing. In strong concentrations of

gas, or by longer exposure to low concentrations, the lungs are

injured and breathing becomes more and more difficult and eventually

impossible, so that the unprotected man dies of suffocation. Death is

sometimes caused by two or three breaths of the gas. Even when very

dilute, chlorine can be recognized by its peculiar smell, which is

like chloride of lime, but stronger and more irritating.

Both chlorine and phosgene also exert a strongly corrosive action on

metals, so that the metal parts of arms must be carefully protected by

greasing them.

The speed with which the gas cloud approaches depends entirely on the

wind velocity. Gas attacks have been made with wind velocities varying

from 3 to 20 miles per hour, _i.e._, from 1-1/2 to 10 yards per

second. In a 9-mile wind, the gas would reach trenches 100 yards

distant in 20 seconds.

Gas attacks have been made on fronts varying from 1 to 5 miles; their

effects at points up to 8 miles behind the front trenches have been

sufficiently severe to make it necessary to wear helmets.

(2) GAS PROJECTILES:

The use of these is not entirely dependent on the direction of the

wind. In gas projectiles such as shells, hand grenades, and trench

mortar bombs, a part or the whole of the explosive charge is replaced

by a liquid which is converted into gas by the explosion. The

explosive force and noise of detonation of these projectiles is less

than that of the ordinary kind, and a large number of them are usually

discharged into a comparatively small space. After the explosion, the

irritant chemicals form a small gas cloud, though some may sink to the

ground and remain active for a considerable time.

For using gas shells, the best condition is calm, or a wind of low

velocity.

Gas projectiles can be used in all types of country. Woods, bushes,

corn fields and clumps of buildings may hold the gas active for a

considerable time.

Two kinds of shell gases are used by the enemy, viz., lachrymators,

which mainly affect the eyes, and poison gases, which may affect the

eyes and are just as deadly as the gases used in the form of clouds.

(1) TEAR, OR LACHRYMATORY SHELLS:

These shells on explosion drive the liquid chemical which they contain

into the air as a mist. They cause the eyes to water strongly and

thereby gradually put men out of action.

Their actual smell may be slight. Large concentrations of lachrymators

begin to affect the lungs and cause sickness, coughing and general

irritation.

(2) POISON SHELLS:

Besides the comparatively harmless lachrymators the enemy also uses

projectiles which contain a gas, the action of which is very similar

to that of phosgene. Because of their slight detonation, these shells

are liable to be mistaken for blinds, but they emit large quantities

of a gas which attacks the lungs strongly and is very dangerous, and

even in slight cases may cause serious after effects.

(3) SMOKE:

The enemy may make use of smoke, either in the form of a cloud or

emitted from shells and bombs. Smoke may be used with gas or between

gas clouds; it may also be used alone to distract attention from a

real discharge of gas, to cover the advance of infantry, or merely as

a false gas attack.

(4) MINE AND EXPLOSION GASES:

The poisonous gases which occur in mines, and which are formed in

large quantities when high explosive goes off in an enclosed space,

_e.g._, from a direct hit in a shelter, or on the explosion of a

charge in a mine, are not protected against by the ordinary anti-gas

appliances. The chief of these gases is carbon monoxide. Protection

against such gases will not be considered in these notes.

Officers are held responsible that all the anti-gas appliances for

protecting their men are maintained in perfect condition, and that all

ranks under their command are thoroughly trained in the use of these

appliances and in all other measures which may affect their safety

against gas.

Summary of Protective Measures:

(a) Provision to each man of individual protective devices.

(b) Arrangement for the inspection of those appliances and training

in their use and instruction in all other measures of gas

defense.

(c) Provision of protected and gas-proof shelters.

(d) Weather observations to determine periods when the conditions

are favorable to a hostile gas attack.

(e) Arrangement of signals and messages; for immediate warning of a

gas attack.

(f) Provision of appliances for clearing gas from trenches and

shelters.

C. Protection of Shelters:

(1) METHODS OF PROTECTION:

Protection of dugouts, cellars, buildings, etc., is given if all

entrances are closed by well-fitting doors or by blankets sprayed with

hypo. solution. Practically no gas passes through a wet blanket, and

the protection depends on getting a good joint at the sides and bottom

of a doorway, so as to stop all draughts. This can be effected by

letting the blanket rest on battens, fixed with a slight slope,

against the door frame. The blanket should overlap the outer sides and

a fold should lie on the ground at the bottom. A pole is fastened to

the blanket, which allows the latter to be rolled up on the frame and

causes it to fall evenly.

Wherever possible, particularly where there is likely to be movement

in and out of the shelter, two blankets fitted in this way but sloping

in opposite directions should be provided. There should be an interval

of at least three feet between the two frames, and the larger this

vestibule is made the more efficient is the dugout.

When not in use, the blankets should be rolled up and held so that

they can be readily released, and should be sprayed occasionally with

water or a little Vermorel sprayer solution.

If the blankets became stiff from a deposit of chemicals, they should

be sprayed with water.

All ranks must be taught how to use gas-proof dugouts, _e.g._, how to

enter a protected doorway quickly, replacing the blanket immediately,

and carrying in as little outside air as possible.

The protection afforded by these means is just as complete against

lachrymatory gases as it is against cloud gas and poisonous shell

gases.

(2) SHELTERS WHICH SHOULD BE PROTECTED:

The following should always be protected:

Medical aid posts and advanced dressing stations; Company, Battalion

and Brigade Headquarters; signal shelters and any other place where

work has to be carried out during a gas attack.

In addition to the above, it is desirable to protect all dugouts,

cellars and buildings within the shell area, particularly those of

artillery personnel. It should be noted, however, that the protection

of dugouts for troops in the front line of trenches is usually

inadvisable on account of the delay involved in getting men out in

time of attack. It is desirable to protect stretcher bearers' dugouts

with a view to putting casualties in them.

D. Protection of Weapons and Equipment:

Arms and ammunition and the metal parts of special equipment (_e.g._,

telephone instruments) must be carefully protected against gas by

greasing them or keeping them completely covered. Otherwise,

particularly in damp weather, they may rust or corrode so badly as to

refuse to act. A mineral oil must be used for this purpose. The

following in particular should be protected:

(1) SMALL ARMS AND S.A.A.

Machine guns and rifles must be kept carefully cleaned and well oiled.

The effects of corrosion of ammunition are of even more importance

than the direct effects of gas upon machine guns and rifles.

Ammunition boxes must be kept closed. Vickers belts should be kept in

their boxes until actually required for use. The wooden belt boxes are

fairly gas-tight, but the metal belt boxes should be made gas-tight by

inserting strips of flannelette in the joint between the lid and the

box.

Lewis magazines should be kept in some form of box, the joints of

which are made as gas-tight as possible with flannelette.

A recess should be made, high up in the parapet if possible, for

storing ammunition and guns. A blanket curtain, moistened with water

or sprayer solution, will greatly assist in keeping the gas out.

(2) HAND AND RIFLE GRENADES:

Unboxed grenades should be kept covered as far as possible. All safety

pins and working parts, especially those made of brass, should be kept

oiled to prevent their setting from corrosion by the gas.

(3) LIGHT TRENCH MORTARS AND THEIR AMMUNITION: