Elements of
Trench Warfare
Waldron

Elements of
Trench Warfare

By
Captain William H. Waldron
29th U. S. Infantry
DISTINGUISHED GRADUATE INFANTRY AND
CAVALRY SCHOOL, 1905
GRADUATE ARMY STAFF COLLEGE, 1906
GRADUATE ARMY WAR COLLEGE, 1911
ASSISTANT DIRECTOR ARMY WAR
COLLEGE COURSE, 1911-12

Author of
"Scouting and Patrolling"
"Tactical Walks"

Price 60 cents

Washington
1917

Copyright, 1917, by
William H. Waldron

NATIONAL CAPITAL PRESS, INC., WASHINGTON, D. C.

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NOTICE

There is a wealth of material in this little book that will interest the soldier. From the illustrations alone he will be able to obtain a good general idea of the subject.

It is essentially a soldier's book, written in language that he can understand. The price has been kept within the limits of his pocketbook.

With a view to securing a wide distribution of the book I desire to secure a representative in every organization in the Army. I have an attractive proposition to make to competent parties.

A letter will bring particulars. My address will be found in the Army List and Directory. If this is not available, a letter addressed as follows will be forwarded to me:

Captain W. H. Waldron,
29th Infantry,
Care of "Infantry Journal,"
Washington, D. C.
(Signed) W. H. Waldron.

CONTENTS

INTRODUCTION

This little book has been prepared with a view to placing before the soldier a store of information on the subject of Trench Warfare as it has been developed on the battle fronts of Europe, and giving him some idea of the nature of the service that he will be called upon to perform when the time arrives for him to do his "bit."

The illustrations have been carefully prepared and arranged to the end that the soldier may gain a fair knowledge of the subject from them alone. The text is intended to treat the subject in a purely elementary manner that the soldier may be able to understand.

The size of the book is such that it may be conveniently carried in the pocket and referred to as occasion requires. The price has been kept down to the point where it is available to the soldier.

If the book assists in his preparation for the front and, by reason of the knowledge that he has gained from it, helps to make him more efficient when he gets there, it will have served its purpose.

The Author.

CHAPTER I

Organization

The normal organization of an intrenched position includes the following elements from front to rear:

1. In front of the position and at a variable distance from the first line fire trench there is a line of wire entanglements. (See Obstacles, p. 4.)

2. Close up to the wire entanglements there is an intrenched post known as the "listening post," which is connected with the first line fire trench by a zigzag communicating trench. (See Listening Posts, p. 18.)

3. Then comes the first line fire trench with attached machine-gun emplacements at convenient points. (See Fire Trench and Machine-Gun Emplacements, pp. 24 and 44.)

4. The fire trench is so narrow that lateral communication along it is effected only with difficulty. In order to provide a passageway a communication or supervision trench is provided a few yards in rear of the fire trench. Passageways lead from this communication trench to the fire trench and to the dugouts located along it.

5. At a variable distance in rear of the fire trench (100 to 200 yards) the emplacements for bomb-throwing apparatus and trench mortars are located. These are connected up laterally by a communication trench which joins with the main communication trench running from front to rear through the position. (See Emplacements for Trench Mortars, p. 41.)

6. From 100 to 400 yards to the rear of the first line fire trench, and generally parallel to it, is the supporting trench or cover for the supports. This trench is invariably provided with strong overhead cover and a system of dugouts for the protection of the troops. (See Cover for Supports, p. 48.)

7. This whole arrangement of trenches is connected throughout from front to rear, and laterally, by a system of zigzag communication trenches.

Take this brief description together with Plate 1, the drawing that accompanies this volume, and study the two until you get the entire system fixed firmly in your mind; that is, until you get a mental picture of all the elements included in the system.

After you have done this, study on through the book in order that you may know the purpose of each of these elements and how one links up with the other.

PLAN OF THE ORGANIZATION OF AN INTRENCHED POSITION
Plate 1

Plate 2

This is the typical system now in use in the European war theaters. Circumstances at certain places may render some variations necessary, and it must not be inferred that the trace of the works is the same throughout. As a rule the types of trenches (altered when necessary to meet local conditions) illustrated herein are the ones in actual use on the war fronts.

All of these trenches and their accessories constitute what is known as the first line. At a distance of from 2,000 to 5,000 yards in rear of this first line a second line, organized in a similar manner, is to be found.

At intervals of from 800 to 1,500 yards along the first line-centers of resistance, or what we know as "supporting points," are located. These consist of fortified villages, or a network (labyrinth) of trenches, provided with every defensive device known to modern warfare. The object of these supporting points is to bring a flanking fire to bear on the intervals between them, with the idea that an attacking force cannot advance beyond them without capturing them.

Plate 2 shows the general scheme of the occupation of a sector of the line by a field army of two divisions.

CHAPTER II

Obstacles

The element of the defensive line nearest the enemy is a line or series of lines of obstacles which are designed for the purpose of:

1. Protecting the lines from surprise.

2. Reducing the momentum of the attack, by breaking up the unity of action and cohesion.

3. Holding the enemy under the effective fires of the defenders.

The conditions that obstacles should fulfil are as follows. They must—

1. Be close to the defender's position. As a rule on the western front they are not more than from 50 to 100 yards distant. If they are too close it may be possible to throw hand grenades from the far edge of them into the defender's trenches.

2. As far as practicable, be sheltered and screened from the enemy. Shell fire is the most effective method of destroying obstacles. If they are not concealed they may furnish aiming points for the enemy's fire against the first line fire trench by his being able to estimate its location with reference to the obstacle.

3. Afford no cover or screen to the enemy.

4. Be so placed that the enemy will come upon them as a surprise.

5. Be so constructed as to be difficult of removal under fire and impracticable to negotiate while still reasonably intact.

6. Be arranged so as not to interfere with a counter attack. The obstacles may have occasional gaps left in them which may be mined.

The different classes of obstacles are: Abatis, low wire entanglements, high wire entanglements, barricades, mines, fougasses, crows feet, military pits with wire entanglements, inundations, etc.

Plate 3.—Abatis.

Abatis (pronounced abatee) consists of branches of trees lying parallel to each other, butts pointing to the rear, and the branches interlaced with barbed wire. All leaves and small twigs should be removed and the stiff ends of branches pointed. The butts are staked or tied down of, anchored by covering them with earth. When more than one row is used the branches overlap the butts of those in front so as to make the abatis about 5 feet high. An abatis formed by felling trees towards the enemy, leaving the butt hanging to the stump, is called slashing.

Plate 4.—Slashing.

Wire Entanglements

Barbed wire is the material most employed in the construction of obstacles. It may be used in the following manner:

1. As a simple trip, for giving the alarm. It is stretched just above the ground and attached to some object that will cause a noise to be made if molested.

2. A simple wire fence, to cause delay and confusion to the enemy in his advance.

3. As an adjunct to tree and brushwood entanglement.

4. As a wire entanglement.

5. As a covering for portable cylinders.

The advantages of the barbed wire entanglement are:

1. It is easily and quickly made,

2. It is difficult to destroy.

3. It is difficult to get through.

4. It offers no obstruction to the view and fire of the defense.

The low wire entanglement is constructed as follows:

1. Drive stakes in the ground until they project about 18 inches. The stakes should be about 6 feet apart, those in each row being opposite the intervals in adjacent rows,

2. The wire is then passed loosely from the head of one stake to another, wound around each and stapled.

3. Where two or more wires cross they should be tied together.

A more useful and efficient modification of the low wire entanglement is made by stapling the wire down the sides of the stakes, allowing five or more feet of slack wire between stakes. Drive the stakes in the ground until the top is flush. This results in a loose network of tangled wires difficult to get through, easily concealed, and difficult to remove.

The high wire entanglement is made by driving stakes so that they protrude from 4 to 6 feet above the ground. They are placed at irregular intervals 5 to 8 feet apart. The head of each stake is connected with the foot of adjoining stakes with the wire loosely drawn, wound around the stakes and stapled fast. Each center post should be stayed by four wires. There should be a trip wire about 9 inches from the ground all the way across the front and another about a foot from the top of the center posts. Barbed wire may then be hung in festoons throughout the entanglement, with no fixed pattern. To increase the entanglement wire may be stapled to the foot of the posts, as indicated in the paragraph above, before they are driven. Large nails should be driven in the tops of the posts with half their length protruding. A number of the wires in the entanglement should be fastened together where they cross. The wire should be passed through paint, if practicable, to take away the bright color. The posts should be painted the color of the surrounding country. Under the conditions encountered on the western front this work has to be done hastily. It is best, therefore, to limit the first stage of construction to just so many strands as will form a nucleus for the whole entanglement, in order that the area may be covered by an obstacle before interruption occurs.

Plate 4a.—Plan of wire entanglement.

Plate 5.—High wire entanglement.

Tight wires help the enemy's advance by forming supports for hurdles. It must be constantly borne in mind that the wires must not be stretched taut.

A portable wire entanglement is constructed by stretching wire loosely around a wooden framework, either circular or square or made on a knife rest, and rolling it into position to close up gaps that may have been made in the entanglement. The illustration shows the wooden framework.

Plate 5a.—Alarm trap.

Plate 6.—Portable entanglement. Constructed in the trenches and rolled into position.

The ordinary repairs to entanglements are made under cover of darkness by working parties detailed for the purpose. Iron posts that can be quickly placed in position are advantageous, their disadvantage being that they may retard bullets that would go through the ordinary wooden posts, thus furnishing just that much cover and protection to attacking parties.

In the construction and repair of entanglements care must be taken to see that they are firmly fastened into the ground with numerous stay posts or "deadmen." This is to prevent the enemy from pulling them to pieces with grappling hooks connected to ropes that lead to his trenches and are attached to powerful windlasses or capstans.

Barricades

Barricades are employed for the defense of streets, roads, bridges, etc. They may be made out of any available material such as furniture, vehicles (overturned or with wheels removed), carts filled with stones, bales of goods, etc.

Where trees grow along the roadside they may be felled across the road. If necessary, barbed wire may be run through the branches to make the passage more difficult.

Plate 7.—Plan of barricade for blocking a road.

Barricades should not as a rule close the road entirely to traffic. Passages are required to allow the defenders to pass through when it is necessary to do so. Hence they should be made in two parts, one overlapping the other, as shown in the illustration.

A fougass is a mine so arranged that upon explosion a large mass of stones is projected against the enemy. An excavation is made in the shape of a frustum of a cone, inclining the axis in the direction of the enemy so as to make an angle with the horizon of about 45 degrees. The sides splay outward slightly. A box of powder is placed in a recess at the bottom. This is covered with a platform of wood several inches thick, on which the stones are piled.

The fuse is placed in a groove cut at the back of the excavation, or the mine may be exploded by means of electricity.

The line of least resistance for the charge must be arranged so that the powder will act in the direction of the axis and not vertically. This is accomplished by throwing the excavated earth on the crest towards the defender's side and ramming it well.

To ascertain the powder charge for any fougass, divide the number of pounds of stone in the charge by 150. This gives the number of pounds of powder in the powder charge. Thus a fougass charged with about 70 pounds of powder will throw about 5 tons of stone over a surface about 160 yards long and 120 yards wide.

Plate 8.—Fougass.

Plate 9.—Vertical fougass.

When broken up a cubic foot of stone weighs about 100 pounds.

A vertical type of fougass is also shown. A charge of 25 pounds of powder should scatter a cubic yard of stones over an area about 200 by 100 yards.

Small Land Mines

Land mines are placed in the line of the advance of the enemy and exploded either by electricity or fuse from the defense. They are made by digging holes from 2 to 3 yards deep, either by excavation or by boring. In the former case the charge is placed in a recess which extends into the solid earth at the side of the hole, which is then refilled and tamped. In the latter case the charge is placed in the bottom of the hole, which is then refilled and solidly tamped. In common earth the powder charge for a 2-yard hole is 25 pounds. That for a 3-yard hole is 80 pounds. The diameter of the crater formed will be about twice the depth of the charge.

The mines may be arranged in one or more rows. The intervals between mines should be such that the craters will nearly but not quite join. The position of the mines should be concealed as much as possible and further sophisticated by disturbing the ground slightly at points where there are no mines and so situated as to suggest a systematic arrangement.

Plate 9a.—Land mine.
F, Line from powder charge to battery.
P, Powder charge.

Inundation

Backing up the water of a stream so that it overflows a considerable area forms a good obstacle, even though of fordable depth. If shallow, the difficulty of fording may be increased by irregular holes or ditches dug before the water comes up, or by constructing wire entanglements in the water. It may be employed with advantage when the drainage of a considerable area passes through a restricted opening, as a natural gorge, culvert or bridge.

Open cribs filled with stones, or tighter ones filled with gravel, may form the basis of the obstruction to the flow of the water. The usual method of tightening spaces or cracks between cribs is by throwing in earth or alternate layers of straw, hay, grass, earth, or sacks of clay. A continuous construction, as shown in the illustration, may be employed. The ends of the dam must be carried well into the solid earth to prevent the water from cutting around them. This type of dam is easily destroyed by artillery fire, and cannot be depended upon.

Plate 10.—Dam construction.

CHAPTER III

Lookout and Listening Posts

Except when the garrison are actually required to man the parapet, they will be kept under cover, with the exception of a few lookouts, whose duty it is to give timely warning of the movements of the enemy.

When the opposing forces are in close proximity to each other mining operations are generally resorted to by both sides to compass the destruction of the opposing works and open the way for an attack.

Lookout and listening posts serve the double purpose of having a few men at the most advantageous places for observation at the front and flanks and providing points at some distance to the front of the first line fire trenches from which listeners may be able to discover the location and direction of enemy mining operations before they really menace the fire trench.

In the normal case there will be some natural cover available. Such, however, is not always the case, and specially constructed observation stations have to be provided.

The posts should be placed in advance of the first line trench, the distance depending upon circumstances which have to be determined in each particular instance. They must be fully protected from reverse fire so that there will be no chance of the observer masking the fire of his comrades manning the fire trench.

Unless the ground is very favorable it will be found difficult to provide for observation above ground. Where there are natural features such as embankments, mounds, hedgerows, ruins of buildings, etc., it may be possible to make provision for observation even by day.

Where a loophole is used, the type having the narrower end outward should be provided.

In the open type of post the observation directly to the front may be greatly facilitated by the use of the periscope. (Plate 11.)

A good, strong parapet thrown up and chopped off at the corners will enable the observer to cover areas from an oblique direction from the post and protect him from fire from the front.

In the covered type the observer is provided loopholes having the splay towards him. These may also be constructed to the oblique rather than to the front. When this is done, provision must be made to cover the entire front of the position from the several posts. (Plate 12.)

Plate 11.—Open type of listening post.

Plate 12.—Covered type of listening post.

Plate 13.—A listening and observation post.

The post may be connected with the first line fire trench by a narrow zigzag trench or by an underground passage. If the former, it must be thoroughly concealed and have no excavated earth visible. If it can be located along a hedge or some other natural feature its location may remain unknown to the enemy for a considerable length of time. Where a communication gallery is constructed the roof and walls must be suitably shored up by casing and supports.

The sentinel in the listening post carries no accouterments. It has been found that the creaking noise made by equipment when the sentinel moves has been taken for mining operations of the enemy by his comrades.

Listening galleries should never be left without a sentinel. There should be a depot of arms and hand grenades near the entrance to the gallery in case men are attacked while on duty from either above or below ground.

Listening will be conducted at specified times, or on some prearranged signal, and for a definite period. During this time all within the listening area, including the trenches, must remain absolutely motionless.

Infantry manning a trench can assist listening by digging a small pit, 6 feet deep below the trench, and running a bore-hole out 20 feet or more.

The enemy is always listening for indications of the direction and position of gallery heads. Work must therefore be carried on with a minimum of noise. Shouting down the shafts of galleries is absolutely forbidden.

When the mining operations of the enemy are detected a report should be made at once to the officer in charge of that section of the trench.

CHAPTER IV

Field Trenches

The next element of the defensive position is the first line fire trenches. These are located so as to have a good field of fire to the front for several hundred yards and so constructed as to give the greatest cover and protection from the fire of the enemy.

An unbroken, continuous trench would be exposed to enfilade fire. A shell, shrapnel or grenade bursting therein would have widespread effect. To overcome these elements the trench is constructed in short lengths, with traverses between them, and technically known as the traverse type.

Better defilade is thus secured and the material effect of any burst is confined to narrow limits.

The trench interval between the traverses is known as the "bay," which should not ordinarily be longer than 18 feet. Longer bays invite heavy casualties in case the trench is enfiladed or a high explosive shell finds its mark.

The illustration, Plate 14, shows a trace of the traversed type of fire trench.

PLAN OF TRAVERSED TYPE OF FIRE TRENCH
PLATE 14.

1. Length of bay, 18 feet.
2. Width of traverse, 5 feet.
3. Length of traverse, 5 feet.
4. Overlap of traverse, 3 feet.
5. Height of traverse depends upon defilade required and practicability of concealment.

Type of Trench

Formerly, protection from the enemy's fire was obtained by thickness of parapet. In the trench warfare of today it is obtained by completely concealing the riflemen in a deep, narrow trench with a very low parapet.

The height over which the average man can fire is about 5 feet or about five-sixths of his own height. This factor determines the height of the parapet above the firing banquet of the trench or the height of bottom of loophole above the same point, when the latter is employed.

The type of trench in general use today is the simple standing trench shown in Plate 15.

Plate 15.—Simple standing trench. 1. Width at top, 3 feet 4 inches. 2. Width at bottom, over all, 2 feet 8 inches. 3. Width of firing banquet, 1 foot 4 inches. 4. Height of parapet above firing banquet, 5 feet. 5. Height of parapet above bottom of trench, 6 feet 4 inches.

PLATE 15a.
Type of INSTRUCTION FIRE TRENCH AT VALCARTIER CANADA
Used in the instruction of Canadian Troops.

Drainage

If a trench is to be occupied for any length of time, especially if much ground or falling water is to be encountered, drainage becomes of prime importance. Many years ago a celebrated military authority asserted that "nothing so saps the courage of a soldier as to wet the seat of his breeches." This may be accepted as a true maxim, especially in cold weather. The trench should therefore be made as dry as possible. The floor of the trench should be given a sufficient slope to the rear where an intercepting drain should carry the water to prepared sumps or to a point from which it can be disposed of by drainage. Provision should also be made to exclude surface drainage from the trenches.

A scheme for trench drainage is shown in the illustrations (Plates 16, 17 and 18).

Overhead cover may be provided as shown in Plates 19 and 20.

Loopholes are made wherever head cover is provided. Where the enemy's trenches are close, there is considerable danger in using them. Collective firing takes place over the parapet. When loopholes are used they should face half-right or half-left and not directly to the front.

Plate 16.—Method of draining trench.

Plate 17.—Details of trench drainage.

Plate 18.—Detail of trench drainage.

Plate 19.—Overhead cover.

Plate 19a.—Overhead cover.

Plate 20.—Overhead cover.

Plate 20a.—Overhead cover.

The disadvantages of loopholes are:

1. The difficulty of concealing firing points. Loopholes give the enemy's snipers an easy mark.

2. They lessen the number of rifles that can be used at a given point.

3. The necessary head cover makes it difficult to get out of the trench quickly.

4. Damaged head cover often spoils a good firing point.

The three types of loopholes are:

1. Narrowest point of the opening nearest the marksman. This type is most difficult to conceal, much of the parapet thickness is cut away and, if of hard material, tends to deflect the bullets into the firer's face. This defect may be remedied somewhat by stepping the surface of the loophole.

2. Narrowest point to the front. Easiest to conceal but gives a limited field of view.

3. Narrowest point midway between the front and rear. A compromise between the first two types.

The following general remarks on the construction of loopholes are taken from a work based upon the experience gained during the war in Europe:

1. The angle of splay is usually 60 degrees. The thicker the parapet the smaller must be the angle of splay.

Plate 21.—Types of loopholes.

2. The marksman holds his rifle in a line connecting the right shoulder, the eye and the object, hence most of the body lies to the left of the rifle. The loophole should be made to the
right, with a niche in the wall of the parapet from the hip to the armpit, to bring the left shoulder well forward. It will be found that this permits the right elbow to be placed on the edge of the parapet.

Plate 22.—Methods of constructing loopholes with sandbags.

3. Box loopholes with screens or blindage may be used, but should be placed by a skilled marksman. The great disadvantage is that the enemy notes these parapet alterations. Steel loophole plates are now provided for this type of loophole, As the Germans sometimes use a steel bullet with great penetrating power, it is advisable to place two plates together to insure protection.

4. With every precaution that may be taken it is difficult to conceal a loophole. A good plan is to deceive the enemy by using painted sandbags and preparing plenty of dummy loopholes.

5. The minimum width of loopholes should be 2-1/2 inches. If narrower than this, it is impossible to use both eyes to judge distances correctly.

6. The parapet should be so sloped that there is a maximum grazing fire when the rifle is fired as it lies on the parapet.

To insure that the bullet will not graze the parapet, although the sights are clear, look through the barrel with the bolt removed.

Communication Trench

Plate 23.—Type of communication trench.

In the first line fire trenches there are so many crooks and turns and the trench itself is so narrow that passage along the same is very difficult. To provide for this lateral communication a trench known as the communication or supervision trench is dug. It runs generally parallel to and a short distance in rear of the fire trench and is connected therewith by zigzag approaches. The factor that determines the distance between the fire trench and the communication trench is that it should be at such a distance that a shell bursting in one of the bays would not destroy the communication trench.

The location of the communication trench with respect to the fire trench and the arrangements of the approaches is shown in detail in Plate 1.

The profile of the ordinary communication trench is shown in Plate 23.

Dugouts

During the artillery bombardment few men are left in the fire trenches. The remainder of the garrison is held under cover a short distance to the rear. This cover is provided by a system of dugouts connected with the fire trench through underground passageways that lead to the communication trench. This arrangement is shown in Plate 1.

A profile of the latest type of dugout is shown in Plate 24.

The solid earth cover is from 12 to 18 feet thick, which gives protection from all but the very largest caliber shells.

Effective resistance is supplied by roofing materials as follows:

1. From shrapnel bullets: 2-inch planks covered with 12 inches of earth.

2. From 3-inch shells: 4-inch planks supporting 4 feet of earth with a top layer of heavy stones to cause an early shell burst.

Plate 24.—Type of dugout.

3. From howitzers of less than 6 inches caliber: 12-inch beams or logs covered with 8 feet of earth.

4. From the largest caliber guns: 15 to 25 feet of earth.

The following table shows the penetration of the German S bullet at a range of 200 yards:

In addition to the regular "dugouts" for the supports, the latest type trenches have squad dugouts just in rear of the bays of the fire trench. These provide shelter during bombardment for the members of the squad not actually required on duty in the trench bay.

Plate 24a.—Section of traversed type of fire trench showing entrance to squad dugout.

Communications

The fire trench is connected with the cover for supports by a system of zigzag trenches having the profile shown in Plate 23. The arrangement is shown in Plate 1.