By the General Staff
I. Principles of Defense in Relation to Artillery
V. The Repulse of Assaults (Barrage Fire)
VI. The Support of Counter-Attacks
VII. Artillery in a Rearguard Action
VIII. Anti-Tank Defence
IX. Trench Mortars
X. Action of Artillery in Enemy Gas Attacks and Smoke Barrages
XI. Withdrawal to Rearward Positions
Appendix I. Diagram illustrating the Disposal of Artillery in Depth
Appendix II. Disablement of Ordnan
In all offensive operations the whole duty of the artillery is to prepare the way for and support the infantry with whom the eventual decision rests. On the other hand artillery must be regarded as the strongest weapon of the defence. For it alone is able to achieve serious effect on the enemy's troops at all times, to hinder or even to stifle his preparations and to effect decisive results by shell fire on masses of the enemy's infantry assembled for or launched to the attack.
These considerations define the role of artillery in defensive operations as under:
One of the essential considerations in the selection of positions for defence is therefore the relative advantages for the action of the defender's and of the enemy's artillery.
Good ground observation and covered positions for the artillery at favourable ranges should always be looked for, and conversely every endeavour should be made to render the position of the enemy in these respects as unfavourable as possible.
The particular missions demanded of the Artillery can only be satisfactorily met if the whole artillery organization of the defence is based on the principles of depth, suppleness and mobility.
Frequent movement to alternative positions is the best means of diminishing the effect of heavy systematic shelling during the preparatory period.
Once the enemy's attack is launched, rigid and purely defensive fire is not alone sufficient to arrest the progress of determined troops advancing on a wide front and to drive them back. Mobile artillery reserves, on the other hand, will prove of the greatest value, for their existence not only denotes a maintenance of the offensive spirit, but also enables a great variety of tasks to be undertaken at short notice. In the main they will be employed with most conspicuous success at places where the enemy has broken into our positions on a fairly extensive front, either by engaging specially favourable targets, or in supporting our attacks. Under certain circum-stances they can be utilized to reinforce the artillery already in line, or to fill gaps which may have originated during the battle.
The successful employment of artillery held in mobile reserve demands thorough preparation; this includes a careful reconnaissance of the whole battlefield as regards the possibilities of movement and most especially of observation, and also well-considered measures for the rapid supply of ammunition. The sudden intervention in the battle by well and boldly handled mobile artillery will always offer chances of far-reaching success. To effect surprise, however, skilful leadership and use of the ground are essential, and these points must receive particular attention in all artillery training.
2. The organization and chain of artillery command are explained in detail in Artillery Notes, Nos. 3 and 4.
A satisfactory organization will not of itself command success. A high standard of drill and training, foresight, and the utmost energy in preparation are just as necessary to the successful conduct of artillery in a defensive battle as they are in offensive operations.
3. The Siting of Artillery in the Defense. The offensive principle of siting all batteries as far forward as possible has evident disadvantages when offensive preparations are not immediately in view.
Barrage batteries especially should not be situated too far forward, nor should they be massed, for under these conditions they may be too easily neutralized by the enemy's artillery before they can open a decisive fire. A distribution in depth provides a certain security against a large amount of artillery being put out of action simultaneously, and makes the enemy's counter-battery work, especially with gas shell, more difficult. A proportion of the Heavy Artillery will be required for counter-battery work during normal trench warfare. To enable this task to be satisfactorily performed, a certain number of batteries must of necessity be sited in forward positions, and, as the object of this is to obtain maximum range from their guns or howitzers, it is clear that counter-battery requirements should have prior claim in the allotment of weapons of long-range pattern. It must be remembered that in the event of an intended offensive by the enemy, his batteries are certain to be brought up to closer ranges in order that they may adequately support his infantry.
The foregoing considerations, combined with the necessity of being prepared to meet a heavy surprise attack on a large scale, which in its initial stages is practically sure to gain ground in certain sectors to an appreciable depth, show how essential it is that artillery, just as much as other arms, should be distributed in depth for purposes of defence.
As a general guide, the artillery of the defence should be disposed on the plan shewn in Plate I. The actual siting of batteries must, of course, largely be governed by the ground and by the situation of the various rearward lines of defence.
As regards Field Artillery, the importance of siting field batteries in such a way as to avoid any dead ground cannot be over-estimated. It is most important that the majority of the 18-pdr. batteries in any defensive sector shall be able to bring fire to bear well this side of our front line. This requirement is much facilitated by siting batteries well back, and this again makes it possible for artillery to carry out several tasks from one position.
4. Alternative, Reinforcing and Rearward Positions
Alternative positions should be maintained for all Field batteries, and, as far as practicable, for those of Heavy and Siege Artillery as well; these positions should be ready for immediate occupation in the event of the original ones being definitely located by the enemy. Constant movement by the heavier natures of artillery is impracticable, but the use of alternative positions and of roving sections or single guns should be exploited by Field Artillery. Such measures, carried out with circumspection and not too frequently, serve to mislead and mystify the enemy.
Positions for reinforcing artillery must be selected, and prepared as far as labour and material admits; some of those maintained as alternative positions may be available for the defence of the front line.
Positions for covering the rearward systems of defence must also be selected and clearly marked, even if labour is not available to undertake their actual construction.
Such positions must be sufficiently numerous to allow both for the withdrawal of artillery from the forward positions and for the advent of such reinforcements as may be expected.
It is, of course, most necessary that the routes to all rear-ward positions should be reconnoitred, selected and definitely allotted.
5. "Dummy" Positions."Dummy" gun emplace-ments often serve a useful purpose, provided that they faithfully resemble real emplacements down to the smallest detail. Tracks up to them must be made and even short lengths of tramway laid. Particular attention must be paid to imitating the blast marks made by the nature of gun or howitzer supposed to occupy such emplacements, as on air photographs the absence of these marks is usually a reason for deciding that a position is unoccupied.
On fine days, when hostile aircraft are up, fires should be lighted close to "dummy" position; "flashes" may be fired from them, provided that an actual battery is firing at the same time. If roving sections or guns occasionally fire from these positions, the illusion will be heightened.
If any real emplacements have been abandoned owing to hostile artillery fire, a few rounds should occasionally be fired from them.
6. Close Defense Guns.Single field guns in advanced positions may prove of great value in case of an attack by infantry or tanks. (See para. 36.)
Such guns should not in principle be so close to our front line or to other clearly defined localities as to be likely to succumb to the effects of the enemy's preparatory bombardment. Their value lies in the ability to deliver a sudden fire over the open sights at comparatively short ranges on either hostile infantry or tanks as they enter our lines, or, more particularly, as they endeavour to penetrate our defensive system. These guns should never, of course, be fired except in the case of an actual attack by the enemy. It is essential that arrangements should be made so that guns can be run out of their pits into the open in case of need.
7. Construction, Protection and Concealment of Battery Positions.It is more than ever important that attention should be paid to concealing battery positions from the air. Camouflage should be constantly improved, and the resulting work studied by means of air photographs.
Regularity is particularly to be avoided. Guns should, as far as possible, be disposed in an irregular line, and as far apart as is compatible with adequate control; the latter consideration not only makes it more difficult to locate them, but also minimises the effect of individual hostile shells.
Blast marks must be obliterated or concealed. Tracks and tramways should never come to a dead end in a battery; they may be advantageously continued on into a "dummy" position.
As regards the protection of positions, the stronger the cover provided (combined with efficient concealment), and the more thorough the organization of the positions themselves, the better able will batteries be, both physically and morally, to fire effectively in the face of a superior artillery on the day of battle.
All work on battery positions should be carried out on a regular system, so that improvement is continuous. As a general guide, the order of importance of work to be carried out on a battery position is:
Arcs of fire should be as wide as possible, and gun emplacements must be so constructed that guns can be run in or out without difficulty. It must be remembered that fire may be required in any direction, and that the embrasure of a gun pit may at any time be blocked by a chance shot.
All battery positions within 3,000 yards of the front line should be wired. This principle should be extended, as labour allows, to all battery positions situated in the various defensive systems. Prepared for all round defence, they may prove of great value as rallying points; batteries will eventually be provided with machine guns, and these, together with the rifles allotted to them, will enable a stubborn defence to be organized by the commanders concerned.
8. Command Posts. Artillery Command Posts must be selected by General and R.A. Staffs in consultation. They must be so sited that they are likely to be out of constant shell-fire, since once communication between artillery commanders and their batteries becomes impossible, or even difficult, organized control ceases.
In the case of infantry and R.F.A. brigades, it is of immense advantage if their respective headquarters can be close alongside one another, always provided that there is reasonable prospect of the artillery commander's signal communications with his batteries and his C.R.A. remaining continuously open. In Divisions and higher formations it is essential that the General and R.A. Staffs should be close together during active operations of any nature.
9. Observation. In the early stages of our offensive battles, at any rate during the period of the actual infantry advance, the great part of the supporting artillery fire is necessarily delivered mechanically in the form of barrage fire and of a general scheme of neutralization of the enemy's batteries. This fact, and the ever-increasing share taken by the R.F.C. in assisting artillery observation, has perhaps led to neglect of the importance of ground observation. Whenever attacking infantry are halted for any considerable time, or as soon as the final objective of the day is gained, the immense importance of ground observation has been exemplified again and again.
In defensive operations, at the moment when the enemy's attack is launched, barrage fire is necessary. It must always be possible to open this fire immediately, in any circumstances and at any hour of the day or night. It must therefore be capable of accurate and instantaneous delivery without observation, and hence be automatic.
But with the exception of this barrage fire, it is not too much to say that observation is essential to the successful application of all artillery fire in a defensive battle. In this case there can be no fire based on pre-arranged programmes, and the possibilities of observation from the air may be severely curtailed. Time will be a matter of vital importance, and artillery fire, if it is to be of any real value, must be accurately delivered where it is most required.
Direct observation from the ground, which under these conditions is the only basis for accurate shooting, therefore becomes a matter of decisive importance.
These considerations necessitate the construction throughout the front of a system of observation posts, with as secure communications as possible (see para. 10). They must be provided so that no portion of the foreground is left unwatched, special regard being paid to the junctions of Corps and Divisions. The hostile country must be kept under observation, not only by day, but also by night, so that the flashes of the enemy's guns may be observed and the work of locating his batteries thus extended.
All Artillery Headquarters, from Corps downwards, should possess a map showing what can be seen of the enemy's defences and territory from each O.P. under their control, and also a photograph of the view from each.
In the construction of O.P.s it must always be remembered that cover from weather and freedom of movement are essential to good work. Concealment must be most carefully studied, and with this must be combined the maximum possible amount of protection from shell fire, so that there may be a reasonable probability of these posts surviving the enemy's bombardment and barrage fire.
It follows that O.P.s should not be nearer to the front line than is absolutely necessary. About 500-600 yards back may be regarded, generally speaking, as a suitable distance, though occasionally they may be as much as 1,000 yards in rear.
In certain parts of the line the configuration of the ground will make it inevitable to have O.P.s in or close to the front line, and in such cases reserve O.P.s must be arranged further back, whence fire can be controlled should the enemy succeed in breaking into our defensive system. Indeed, the observation system must be established in depth just as much as the batteries themselves. Every Group Commander, whether of Field or Heavy Artillery, should establish an observation station for himself in the close vicinity of his headquarters whence a general view of the country can be obtained and from which he can, if necessary, see for himself what is going on in his immediate front. A "crow's nest" in a tall tree will often meet the case.
Every battery must establish an O.P. close to its gun position, ready to be occupied should the enemy succeed in breaking through the forward line of resistance. In some cases it may be necessary to have more than one of these O.P.s available, in order to deal with any of the various situations that may arise.
All reserve O.P.s should be occupied as soon as an attack develops, or sooner if communication with forward O.P.s is lost.
O.P.s must also be selected, marked and tabulated in rearward areas in connection with the gun positions chosen for the support of each successive line of resistance. To what extent these can be prepared must depend on the labour available.
It is advantageous if all O.P.s are wired in and if they can be protected by flanking machine gun fire.
10. Signal Communications. The high importance of observation demands as a corollary a system of communication calculated to withstand the natural conditions involved by a hostile attack.
All means of communication available for the use of the Artillery must be considered and systematically improved in consultation with the Senior Signal Officer of formations.
The following points should receive attention:
Every artillery O.P. that is manned by night should be provided with a complete equipment of "S.O.S." light signals. Those should invariably be used in addition to any telephone or other signal message sent. "Repeating stations" must be established wherever necessary.
The rapid transmission of "Alarm" signals to the actual guns requires the greatest care and forethought. The only sure test of a thoroughly efficient system of communication is that messages get back from the front line to the guns at once at night or in foggy weather, even though the telephone system has broken down.
11. Liaison between Artillery and Infantry. As already pointed out in paras. 1. and 2, flexibility of organization and mobility are essential to the successful employment of artillery in the defensive battle. These principles demand the closest touch between artillery and infantry. Personal liaison between the commander of an infantry formation and the commander of the supporting artillery is the best form of liaison on all occasions. It is for this reason that it has been laid down (see para. 8) that the headquarters of such commanders should, if possible, closely adjoin each other. If is not feasible, then liaison between artillery, both R.F.A. and R. G.A., and infantry must be ensured by the attachment of responsible artillery officers to the infantry formations concerned.
As regards liaison between batteries and battalions, it is to be understood that the right place for a F.O.O. during the hours of daylight is at his O.P. There he can see the front with which he is concerned and is responsible for bringing fire to bear if required. Thus he must be able to pass a call for fire more quickly than it could possibly be conveyed if emanating from a liaison officer with a battalion.
By night (apart from O.P.s manned for counter-battery purposes and those used as repeating stations for S.O.S. calls) F.O.O.s are unable to carry out their primary dutyobservationand a liaison officer should remain with every battalion.
The closest touch between R.G.A. Brigades and the Division whose front they cover must always be ensured.
12. Co-operation of R.F.C.Photographic records of the areas in which gun positions are likely to be constructed are of great importance. These photographs should be taken at regular intervals in order that the progress of the enemy's preparations may be followed.
Once the battle commences, the principal role of the Royal Flying Corps will be observation for the artillery. At this period, therefore, everything must be subordinated to the duty of keeping our own artillery machines in the air. If this object can be attained it will be of far greater assistance to the infantry and artillery, though invisible to them, than any amount of low-flying or bombing against the enemy's front line troops.
13. Fire Direction and Control.Ability to open at once an accurate fire at any hour of the day or night must be the ideal of every battery, and all artillery commanders must seek to develop in this respect a constant improvement in their commands. When any important firing is to be carried out, or when a condition of abnormal activity prevails, observation posts should always be manned by officers of some standing and discrimination.
Orders as to checking ranges daily on datum points, routine firing and concentration schemes; the provision of battery boards for reinforcements, as well as for batteries in the line; measures to improve co-operation by Observation Groups, Sound Ranging Sections and Balloons; care of material; the system of transmitting orders and information from all sources to the guns; arrangements for opening annihilating and barrage fire; all these matters require constant attention, and improvement will only be marked if commanders not merely issue orders on these subjects but by test and by personal supervision ensure a satisfactory execution of the principles laid down.
Full consideration must be paid to the advantages to be derived from enfilade fire and from concentrations of fire.
Enfilade fire over parts of the enemy's front line may be possible from batteries sited in normal positions, but it should be particularly regarded when siting forward guns, or employing roving sections. Under the ordinary conditions of trench warfare the amount of artillery in the line is not very large, and it is therefore an economy in gun-power to arrange for enfilade fire, as far as is possible, without infringing the principle of distribution of artillery in depth. The value of this nature of fire is apparent not only for routine firing but also in counter-battery work, bombardments, and, when safety considerations admit, in the defensive barrage.
Concentration of fire is a principle applicable to many situations. Its object is to exert a maximum artillery effort on a given target, combined very often with an intention to effect surprise.
It follows, therefore, that careful arrangements and clear orders are necessary if this form of fire is to attain the best results and is to be capable of being carried out at short notice. Every Artillery Staff should maintain a chart showing what batteries can concentrate their fire on each map square; by this means it is possible to see at a glance the number and calibre of guns that can fire on any given target.
A concentration of fire by several batteries in no way implies a haphazard rain of projectiles over the target concerned. Each battery must be assigned a definite portion the target or a distinct lane or area to cover with fire. To what extent ranging should be carried out depends upon the target and on the situation; ranging, for instance, is inapplicable to concentrations of fire on important fleeting targets ("LL" call), while on the other hand accuracy of fire is essential to the deliberate destruction of defences.
To obtain the benefits of surprise and to achieve the greatest moral results, concentrated fire for effect should always be opened simultaneously. It should be remembered that a concentrated fire will be the more effective in accordance with the care taken in the selection of the batteries to take part, with regard to their nature, ammunition and line of fire; oblique and enfilade fire, as already pointed out, present considerable advantages in this circumstance.
14. Routine Firing.Artillery fire during quiet periods of trench warfare tends to become spasmodic, and therefore wasteful of ammunition unless definite principles of conduct are employed.
To what extent the initiative should be taken in artillery action against the enemy depends entirely on the general situation, and is a matter for the decision of the High Command. On the other hand the enemy's activity must be countered, when necessary, on clear and organized methods.
Artillery "retaliation," the automatic discharge of a number of rounds at the opposing trenches, is useless. When the action of the hostile artillery becomes so aggressive as to demand reprisal, our action should take the form of an organized, fierce and concentrated fire against definite and selected targets whereon appreciable damage is likely to be caused. Care should therefore be taken not to shell empty trenches with shrapnel; when it seems best to direct our fire on the enemy's trenches, a definite target (machine gun or trench mortar emplacements, dug-outs, etc.) should be selected for destruction.
Shrapnel fire may, however, be employed with great advantage after a destructive shoot with the object of inflicting casualties on repairing parties.
It is advisable that all ordinary shooting (harassing fire, engagement of working parties, small reliefs, etc.) should be carried out by roving guns or by single guns or sections sited some few hundred yards away from the main battery position, which by this means can be kept "silent." It is a mistake to unnecessarily disclose guns, the presence of which it is desired to conceal.
15. Mobile Reserves.That mobility is the essence of artillery action in the defence has been emphasized in the opening section of this book and the application of this principle occurs at all stages of the defensive battle. A proportion of the artillery at the disposal of divisions and of higher formations must always be kept as a mobile reserve so that artillery may with certainty be available, both to reinforce a threatened front and to support the counter-attack (see Section VI.) by surprise fire.
16. Vulnerability of Artillery Teams.Care must be taken to avoid, as far as possible, exposing artillery horses to attacks by low-flying enemy aeroplanes. For this reason wagon lines should not be massed together, and every opportunity should be taken to keep horses under cover from view. Artillery on the march presents a vulnerable target and all movements should therefore be carried out as smoothly and expeditiously as possible.
17. Natures of Hostile Attack.A hostile attack on a large scale may be launched, broadly speaking, in one of two ways; either with the object of achieving the utmost measure of surprise, or after full artillery preparation.
In the first case the enemy will make every effort to conceal his intentions, and, should he succeed in doing so, the counter-preparation of the defence will have to rely on the immediate development of annihilating fire or, possibly, only of barrage fire at the last moment.
If, on the other hand, the enemy intends to deliver an attack after full preparation, numerous indications will inevitably be forthcoming; widespread railway construction, the digging of new battery positions and trenches of various natures, increased wireless and aircraft activity, the formation of dumps and the arrival of new batteries on the front are among the number. In this case the artillery counter-preparation of the defence will be able to observe in their entirety the principles laid down in the following paragraphs.
18. Definition of "Counter-Preparation." The term "counter-preparation" in its wide sense includes all the measures taken by the defence to hinder the enemy's preparation for an attack. It must automatically come into being from the first moment when a hostile intention to attack is suspected.
The characteristics of counter-preparation are therefore clearly defined, and, as far as artillery is concerned, consist of:
It is clear that material advantage will be derived if the defence can succeed in opening the artillery battle first. It is therefore essential that all measures of counter-preparation should be fully thought out and arranged, so that they can be put into immediate execution, with the object of hampering the enemy's preparations from the very outset, and before he is in a position to develop the full power of his artillery.
19. Counter-Battery Work. The principles and practice of counter-battery work under varying conditions are fully discussed in "Artillery Notes, No. 3Counter-Battery Work" (S.S. 139/3), and "Co-operation of Aircraft in with Artillery" (S.S. 131).
It only remains therefore to emphasize those points which are particularly applicable to the circumstances of the defensive.
The first principle is always continuity of counter-battery work on organized lines; that is to say, relentless energy in counter-battery intelligence and persistent destruction of hostile batteries in accordance with the resources available and the requirements of the moment.
As soon as an intention on the enemy's part to attack is apparent, or even suspected, effective counter-battery work becomes a matter of exceptional importance to the defence. By means of continual losses the fighting power of the hostile artillery may be impaired to such an extent that it will be unable adequately to fulfill its chief mission, the preparation of the infantry attack. Moreover, if the enemy's batteries arc strongly attacked by our artillery they will be less able to bombard our defensive organizations and infantry gar-risons, whose fighting power will thus be maintained till the infantry combat begins. It is, however, a vital con-dition of the defence that at the moment when the enemy's attack is launched, a prompt, accurate and adequate artillery fire shall he brought to bear on his infantry. If, therefore, the numerical superiority of the enemy's artillery is such that the counter-battery duel must inevitably turn to his advantage, then the counter-battery work of the defence may have to be severely curtailed. Under these conditions the enemy's superiority may best be countered by a judicious use of alternative positions, by fire to destroy the dumps, railways, roads and tracks by which the enemy's batteries are fed, and by strong concentrations of gas shell at opportune moments. The exhausting effect produced by persistent gas shelling on the detachments of hostile batteries situated in localities where gas is not easily dissipated should be borne in mind. The bombardment of observing stations is another matter that must not be overlooked.
20. Bombardment of Rearward Organizations and Harassing Fire.The principles of harassing fire in the offensive (see "Artillery in Offensive Operations," S.S. 139/4, Section V.) and in the defensive are the same, but this form of artillery action assumes in the defensive even greater importance. If successfully applied, it may well cause very serious losses and, at least, delay the enemy's offensive action, thus contributing a distinct point to the favour of the defence.
The essentials to successful fire action in this respect are:
The targets selected should include important railway centres and junctions, billets, headquarters, signal centres and approaches and communications of all natures.
Works in the neighbourhood of the enemy's front system of trenches that have been subjected to bombardment by the artillery of the defence must also receive vigorous attention.
Gas-shell bombardments may be very effective under suitable conditions. These shell may be profitably employed in various ways, provided always that weather conditions are not unfavourable to their use and that they are expended in sufficient quantity. The principles of gas shelling are laid down in S.S. 134 "Instructions on the Use of Lethal and Lachrymatory Shell." It must always be remembered that gas shell will have the greatest effect against living targets who are, by reason of their duties, unable to escape from the infected area. It is for this reason that gas shelling assumes such an important place in counter-battery work. (see "Artillery Notes, No. 3Counter-Battery Work," Section V., 37.) A continued bombardment will prove most exhausting to the gun detachments, and will eventually reduce them to impotence. In this connection it may be remarked that a gas shell bombardment of batteries sited close to roads or other main avenues of approach will often produce a double effect, neutralization of the batteries and also denial of the road, etc., to traffic for some time.
Gas shell will also be effective against concentrations of troops in assembly formations or in billets and bivouacs, especially in valleys, woods, quarries and other localities where the effect of wind is lessened. In order to obtain the greatest effect a gas shell bombardment should be always initiated as far as possible as a surprise; but, apart from this, gas shelling at all times compels the enemy's troops to put on their masks and thus hampers their activity and tends to produce exhaustion.
Gas shelling by night conduces to surprise, is generally favoured by weather conditions and is particularly effective in that it denies sleep or rest to those attacked.
As in offensive operations, infantry must co-operate with artillery by means of direct and indirect machine-gun fire. Special measures should be taken to deal with any known or suspected reliefs or assemblies of troops or tanks. In all fire of this nature the use of roving guns and sections should be exploited to the utmost. This primarily applies to harassing fire on the enemy's forward zone, but the greater the extent to which the principle can be adopted, the less will the enemy be able to neutralize the guns that cause him annoyance and loss. Careful organization is a matter of the greatest importance, as without this it will inevitably occur that certain targets receive an unnecessarily large volume of fire, while others are neglected.
On no account must harassing fire be permitted to die down during the early hours of the morning.
21. Destruction of the Enemy's Infantry Defences.To what extent destruction by the defender of the enemy's trenches and strong points is of value is a matter demanding due deliberation. The destruction of selected points in the enemy's defensive organization is, generally speaking, a necessity for the attacking force in order that material obstacles to the advance of the assaulting infantry may be sufficiently reduced.
Where the defensive is concerned, the object of destroying the enemy's trenches and strong points is based on other considerations.
Wholesale destruction of the opposing trenches is out of the question; partial destruction will not prevent the delivery of an attack. Therefore, whatever ammunition is devoted to such tasks must be expended with a definite object in view.
An enemy preparing to deliver an attack can be materially damaged in three ways by means of fire against his trench system.
For these purposes, zones, areas or lanes must be allotted to the artillery of the defence just as for the preparation of offensive operations. Accuracy of fire, and therefore, observation, are of the utmost importance under defensive conditions, for it is essential that the defending artillery, which will usually find itself numerically inferior, must compensate for any such inferiority by technical superiority of fire. Destructive fire by night will therefore rarely be justifiable, though short and sharp bursts of fire designed to inflict casualties on living targets should constantly be employed.
22. Destruction of the Enemy's Infantry (Annihilating Fire).The casualties caused among the enemy's troops by harassing fire and by the bombardment of his infantry defences will be commensurate with the forethought and accuracy with which such artillery fire is applied.
But as soon as an attack threatens, special measures must be brought into force with the object of causing the enemy's infantry, while assembling for the assault, such losses that the attack will not be delivered at all, or, at least, only half-heartedly. An annihilating fire must be promptly directed on those trenches, dug-outs, communication trenches and dips in the ground wherein the attacking troops, and possibly tanks, are believed or are actually seen to be massing. Careful and continuous observation, both from the ground and from the air, of the enemy's lines and back areas is important in order that any massing of troops by the enemy may be noticed in time and fire opened at once on such targets, with observation if possible.
The threat of an attack, however, by no means depends solely on actual sight of the enemy's assembling troops; it may be betokened by the approach of abnormal numbers of aircraft, by the presence of tanks or by an intense bombard-ment. Again, an intended attack may be given away by prisoners, deserters, or listening posts.
It should be borne in mind that attacks on a grand scale, especially if accompanied by tanks, are likely to develop about dawn. If, therefore, an attack by the enemy is expected shortly to take place, bursts of annihilating fire shortly before daybreak and occasionally before dusk may bring about great results, especially if accompanied by increased harassing fire during the hours of darkness.
It is obvious that a violent fire cannot be maintained for an indefinite period, and hence annihilating fire should be reserved for moments of maximum tension. At other times the enemy's bombardment must be met by the measures described in the previous paragraphs.
Annihilating fire, to produce its full effect, must be con-centrated as regards both time and space, and should therefore consist of short bursts of rapid fire. The principle of concentration demands in its turn a careful organization. Areas or zones must be allotted to the various natures of artillery, and, as far as possible, targets should be allotted beforehand to batteries. Schemes for annihilating fire must deal with a general attack along a whole Corps front and also with attacks confined to divisional and brigade sectors.
Although premature interruption of counter-battery work is to be avoided, at moments of extreme tension the engage-ment of the enemy's batteries becomes a matter of minor importance, and the full power of the defending artillery must be devoted to the overwhelming of the enemy's infantry. At the same time it must always be possible to engage at once especially favourable or dangerous targets, such as columns in movement in back areas or assembled tanks, or to afford support to neighbouring sectors. It is also essential that annihilating fire should be capable of immediate conversion to barrage fire should the enemy's infantry succeed in leaving their trenches.
The foregoing considerations exemplify very strongly the need for flexibility in the artillery organization of the defence (see paras. 1 and 2). This suppleness must ever be regarded as a cardinal principle, as without it the ability of the artillery to meet its many obligations will also be wanting.
23. The Principles of Barrage Fire.The object of barrage fire is in the first place to destroy an enemy during the actual delivery of his assault, and secondly, to prevent the advance of his supports and reserves, thus paralysing the attack. The essence of effective barrage fire is that it shall be of the greatest volume possible, accurately placed and automatically available under any circumstances and at any time.
The quantity of field artillery allotted to any particular front during periods of normal trench warfare is such that the density of the barrage which can be put down to break up an attack on a large scale will not suffice for the whole front.
Artillery barrage arrangements must therefore aim at denying to the enemy an advance against the more important tactical features of the defence, rather than to establish a uniform and therefore comparatively weak barrage along the whole front. For the defence of the intervening portions of the line reliance must be placed on machine gun and trench mortar fire.
It follows that the selection of the fronts to be covered by barrage fire rests primarily with divisional commanders, and that co-operation between divisional artillery and machine guns must be of the closest.
The advent of artillery reinforcements will naturally increase the front that can be adequately barraged.
It must be clearly understood that at the critical moment, when the enemy's infantry leave their trenches to attack, every single weapon of the defence must be devoted to their destruction. For the time being counter-battery work must cease. Artillery, infantry, machine guns and trench mortars must all combine with the object of mowing down the advancing waves and to shatter those waiting in readiness in rear.
24. The Field Gun (18-pdr.) barrage.In principle field gun barrage fire should be put down as close as possible in front of the defender's front line; the safety of the front line garrisons must, however, be definitely assured.
If the opposing trenches are so far apart that the enemy's front trench does not lie within the 100 per cent. zone of the barrage on its original line of delivery, the barrage should search forward as far as the enemy's front line and then creep back to its original line.
Where, on the other hand, the opposing trenches are so close together that the barrage cannot be safely brought down upon the enemy's jumping-off trenches, much of the value of the barrage is lost. The task must then be left to trench mortars, machine guns and rifles, while the field artillery fire is directed upon the enemy's support line and nearer communication trenches.
Although frontal fire facilitates observation and communication, the value of enfilade fire in the barrage must always be remembered, particularly where the amount of field artillery available is small. It will often be difficult to arrange, but it greatly assists to strengthen or complete the barrage curtain.
25. The Field Howitzer and Heavy Artillery Barrage.The field howitzer barrage will generally follow the same principles as those of the field gun barrage, strengthening the latter, but necessarily, for safety reasons, being placed at a somewhat increased distance from our front line.
The part taken by Heavy Artillery depends chiefly on their natures and on the distance at which fragmentation of their shell on bursting is dangerous to our own troops.
Howitzers with No. 106 fuze are a formidable man-killing weapon, and high velocity flat trajectory guns have great shell power and deep searching effect. The role of 6-inch howitzers is essentially to increase the barrage proper by fire to prevent the advance of the enemy's troops waiting in rear to follow the foremost waves. The heavy howitzers and long-range guns may be said to continue to deliver annihilating rather than barrage fire, inasmuch as their specific task is to tie to the ground and to destroy the enemy's supports, reserves and reinforcements.
26. Organization of the Barrage.The selection of "S.O.S." lines, the density of barrage fire and the rapidity with which it can be opened must be the particular concern of the General Staffs of Corps and Divisions. Barrage fire entails a great strain on personnel, material and ammunition resources, and it is therefore of the very highest importance that it should never be called for except under the actual circumstance of attack. The more completely this principle is accepted, the more fully will the artillery appreciate how incumbent upon them it is that their barrage fire shall, when called for, invariably reach the highest stage of perfection. On the other hand, it is clear that the more effectively annihilating fire and other previous artillery tasks are carried out, the less often will a hostile attack be able to materialise. Barrage fire will ordinarily be called for by infantry or by artillery observers by means of the "S.O.S." call, that is to say, by means of light signals, and confirmed by telephone messages; visual signalling and every possible form of communication must be effectively organized as alternative means of getting this message through to the guns under all conditions (see. para. 10.). It is impossible to pay too much attention to ensuring that barrage fire shall be opened with the least possible delay. At the same time, battery, section and single gun commanders must by their personal diligence be prepared to open barrage fire even without the receipt of a "S.O.S." call. This particularly applies by night, when observation is often impossible; an intense hostile bombardment or the outbreak of a violent fusilade may justify the immediate opening of barrage fire without orders. Any battery, etc., commanders opening fire under such circum-stances must, of course, take immediate steps to discover the real situation.
The duration of barrage fire on the receipt of a "S.O.S." call and the rates of fire for the various natures of artillery must be laid down by Armies and Corps. It must be remembered that to continue firing on "S.O.S." lines at barrage rates for an indefinite period is not only wasteful in every respect, but cannot be justified by results. The enemy's attack must either have failed or to some extent succeeded, and in both cases the original distribution of barrage fire can no longer be entirely applicable.
It is advisable that orders should lay down a high rate of fire for the first five minutes or so, the rate then gradually decreasing unless a further "S.O.S." signal indicates that barrage fire is still required.
Should the enemy succeed in entering our lines, barrage fire must be brought back on to those portions of our trenches occupied by him. Such action must be definitely warranted, either by demand from the infantry or by the actual observation of artillery observers; in any case, great care must be taken to describe explicitly where fire is required. It is this contingency that renders it so important that the majority of barrage batteries shall be able to direct their fire well this side of our own front line.
At the same time part of the available artillery must be devoted to preventing the advance of the enemy's supports and reserves.
The role to be taken by machine guns in repelling hostile assaults must be carefully worked out and co-ordinated with the artillery arrangements. The necessity for covering those parts of the front untouched by artillery fire and also the advantage of strengthening the artillery barrage by means of machine gun fire must both receive full consideration.
Artillery commanders must work in close personal touch with Divisional machine-gun commanders and the officer in charge of machine guns at Corps Headquarters, so that the best results may be obtained from the combined efforts of the two arms.
One point may require special attention during winter months. Ground that is ordinarily marshy may become frozen over, and so for the time being be passable to infantry. This possibility must receive due consideration in the selection of "S.O.S." lines, and arrangements made temporarily to barrage any frozen surfaces that may be adjudged important from the point of view of the defence.
27. The Support of Neighbouring Sectors.It should be possible to switch barrage fire from one area to another as if by word of command. But to what extent barrage batteries should in practice be directed from their own "S.O.S." lines to strengthen the barrage of a neighbouring sector is a matter that demands special consideration. In the case of hostile trench raids, once the enemy's point of attack has been definitely established, it will usually be justifiable to afford any additional assistance required, particularly as far as Heavy Artillery is concerned. But in the event of a hostile attack on a large scale, or even of a raid where the front of attack is not clearly defined, a premature diversion of the fire of barrage batteries from their own front is to be strictly avoided. For until the situation is clear, such a diversion of fire may result in leaving a sector devoid of its artillery protection in the face of a subsequent attack, without adding very effectively to the barrage of the adjoining sector. Where it is decided that assistance can be given to some extent, it will be most economically and effectively afforded by means of enfilade or oblique fire. All measures of assistance must very carefully worked out and periodically practised.
28. Principles of Artillery Action.Efficient artillery support to the counter-attack will require the most resolute action and the exercise of the highest form of initiative; all artillery commanders, including Battery and Section Com-manders, must be trained to act, when the occasion arises, independently and with complete self-reliance. Besides the power of quick and sound decision, mobility, reconnaissance and observation are essential to successful artillery action in support of counter-attacks.
29. Immediate Counter-Attacks.If the enemy succeeds in entering our front line trenches, the first mission of the artillery is to cut off the enemy's supports and reserves by means of annihilating fire and at the same time to bring back the barrage on to those parts of the line captured by him. (See para. 26.) Observation from the ground and from the air and communication with the infantry must be re-estab-lished, if interrupted, in order that artillery fire may quickly be concentrated where it is most required, and that our infantry may not be hampered in their counter-attacks by our own artillery fire. At this time the employment of isolated guns and of mobile artillery units (batteries and sections) which know the ground may well result in striking success. Mobile units should either have their teams close to hand or may occupy positions in observation. (See F.A.T., Chap. VIII, Section 184.)
Boldness must form a marked characteristic of their action, so that the utmost benefits of surprise may be afforded by their fire and that the infantry may be conscious of vigorous and visible support. The enemy's assaulting troops will still be in ground unknown to them, and his artillery will, in all probability, be unable to locate the silent or mobile artillery of the defence. To facilitate the advance of such artillery under heavy shell fire, every opportunity should be taken of utilising gaps and pauses in the enemy's fire. This again calls for rapid reconnaissance and quick decision.
If the early counter-attacks by our infantry fail and the enemy succeeds in breaking further into our system of defence, the primary duty of the artillery is to arrest his advance. The first essential to this end is a well-devised system of observation posts throughout the various zones of defence. (See para. 9.) These posts must provide a good view, if possible, without any gaps, not only over all the ground in front of our lines, but also over the area between and in rear of them. With such powers of observation, the mission of the artillery is greatly facilitated. A careful distribution of fire and co-operation with mobile artillery reserves and with rearward machine guns must be fully prepared beforehand in order that the enemy's advancing infantry and also his reserves may both be suitably engaged. Flank guns of field batteries must be pulled out of their pits (see para. 36) so as to be able to engage the enemy over the open sights from whatever direction he approaches. Batteries, too, must make the utmost use of their rifles and machine guns, in case of need.
It will be of considerable assistance at this critical stage in the battle if one or two field batteries in each divisional sector have been placed in action at a distance of 5,000 yards or so behind our front line. Strongly entrenched and remaining silent till the time of assault, they will be able to support counter-attacks in their initial stages while mobile units are coming into action.
30. The Decisive Counter-Attacks.The employment of artillery to support decisive counter-attacks, carried out in accordance with orders issued by the Higher Command, must be based on the principles laid down for the offensive battle. (See Artillery Notes, No. 4, "Artillery in Offensive Operations," S.S. 139/4.)
It will, however, be particularly important that the flanks of the counter-attack should be fully secured by fire and that the protective barrage subsequent to a successful attack shall be strong in volume and deep in distribution. The principles of artillery preparation for such a counter-attack are precisely similar to those for an offensive battle, though time may necessarily be short. That an adequate force of artillery and of ammunition with the guns is available and can be maintained must above all be ensured.
In working out the details of the artillery preparation and support, special attention must be paid to the question of whether the artillery available on the ground is in a position to lend its full weight. If it is not in a position to do so, then part of it must be withdrawn and be re-established in new positions, or additional artillery must be allotted to the counter-attacking force from the outset. (See F.A.T., Chap. VII., Section 163). In either case, a certain number of mobile batteries should always form part of the force detailed for the counter-attack so as to contribute to the possibilities of surprise by decisive fire at short ranges from unlocated positions.
31. Co-operation between Artillery and Infantry.In all cases where mobile artillery is detailed to support a counter-attack, of whatsoever nature, it is essential that the commander of the artillery should have opportunity of getting into personal touch with the commander of the counter-attacking force.
"Whenever a subordinate artillery commander is allotted a task necessitating co-operation with a certain force of infantry, whether he is placed under the orders of the com-mander of that force or not, it becomes his duty to open communication with its commander, reporting to him in person, if possible, in order to obtain full information as to the character of the operation that he is to support and as to the proposed method of its execution." (F.A.T., Chap. VII., Section 153.7.)
The infantry commander must indicate the targets on which he wishes the artillery to fire, but battery commanders must naturally not wait for these targets alone. Fire must on all occasions and without orders be directed on whatever holds up the infantry of the counter-attack, especially machine guns.
In principle some of the batteries, or even sections, allotted to the counter-attack should follow the infantry as far as possible, moving up over the open, and rely on firing with direct observation and over the open sights.
Besides the necessity of arranging that the commander of the mobile artillery detailed to support a counter-attack shall establish personal touch with the commander of the counter-attacking troops, it is particularly important in the case of early counter-attacks in force that the artillery already in the line shall be made aware of the conditions of the intended counter-attack. Unless this is ensured, the success of the counter-attack may be limited by the action of artillery unaware of the situation. At such a time normal com-munications are liable to be interrupted to a greater or less extent, and the difficulty of directing the fire of the artillery in the line will thereby be increased. Every endeavour must therefore be made to establish communication between counter-attacking divisions and the Headquarters of Divisional Artillery, Corps Heavy Artillery, or, at least, Brigades R.F.A. and R.G.A. already in the line. Generally speaking, the action of such artillery must necessarily be devoted to preventing the approach of hostile reinforcements, while all resistance opposed to the attacking infantry must be overcome by the artillery attached to the counter-attack troops.
In the case of decisive counter-attacks, delivered after full reconnaissance and preparation, no difficulties should arise on this account.
32. Under certain conditions it may prove advisable for a force acting on the defensive to undertake a rearguard action, at any rate for a time, as, for instance, when deliberately withdrawing over a considerable distance to fight on a Battle Zone deliberately chosen and prepared in advance.
The principles of artillery action in such circumstances are laid down in F.A.T., Chap. VII., 166; this section should be carefully studied. Instructions as to the successive positions to be occupied by the artillery of the rear-guard should have been prepared beforehand and made known in time to those concerned. It is of particular importance that the routes of withdrawal for artillery shall have been carefully selected so as not to clash with the requirements of other arms, and that arrangements for the supply of ammunition to artillery of all natures shall have been worked out in detail for each step of the withdrawal.
In the face of a powerful hostile artillery, main roads running straight back from the front, villages and other defiles should, of course, be studiously avoided, as far as possible. Visual observation will, as in all phases of defensive operations, be a matter of vital importance in order that any false step made by the enemy and every favourable target presented by him may be met by an immediate and decisive artillery fire.
33. "Instructions for Anti-Tank Defence."Anti-tank defence is dealt with in detail in S.S. 203, from which the following paragraphs are quoted. The pamphlet in question must, however, be studied in connection with the general action of artillery in the defensive.
34. "Artillery the Chief Means of Defence."Experience shows that artillery fire forms the most effective defence against tanks and that all other arms and weapons can only be regarded as subsidiary means.
"The moral effect produced by this new weapon of offence is considerable, and tanks should therefore be engaged at the earliest opportunity.
"But, as has already been stated, it is not so much the actual tank itself that constitutes the danger as the assistance which it offers to the enemy's infantry to break into our defences. Hence, it is essential that only those guns which have been specially detailed for the purpose should deal with tanks, all others devoting their whole energy to destroying the enemy's infantry."
35. "Organization of Defence in Depth.""Artillery defence against tank attack, just as against infantry attacks, should be organized in depth both as regards the artillery holding the line under normal conditions and especially with regard to the plan for reinforcing the front where attack is threatened or takes place. Such an organization will ensure that any tanks which escape early destruction will have to face artillery fire at all stages of their advance."
36. "Engagement of Tanks.""The engagement of tanks prior to an attack depends primarily on their discovery by aircraft and on careful examination of aeroplane photographs. Tanks thus discovered will be engaged under the zone call system, or, if time allows, be deliberately destroyed by the concentrated fire of several batteries.
"At the beginning of an attack hostile tanks will have to pass through the defensive barrage fire, which should make it difficult for them to penetrate our lines.
"If the enemy's tanks are not stopped before reaching our trenches, the object must be sought by the employment of guns using direct laying, i.e., by forward guns, dug in and strongly protected. Sections of field guns should be brought up on the first warning of a tank attack to positions whence they can engage such targets over the open sights.
"Should even a few of the enemy's tanks succeed in passing through those forms of artillery defence already considered, they will by then have advanced far into the defensive system, and it becomes imperative to stop their further advance.
"It may be advisable to site single guns specially for this work, in the main area of field artillery concentration.
"Apart from this, in all batteries one or two guns (the flank guns are the most easily handled) should be told off to be run out, in the event of a tank attack, into positions in the open close to their batteries. Such positions must have a good view to front and flanks, so that direct fire can be brought to bear on advancing tanks.
"This procedure has been adopted by the enemy, and has in recent operations been the cause of the chief losses to our tanks. Prompt and accurate fire by these guns will restore what otherwise might prove to be a dangerous situation. Regardless of the position of our own troops, they must fire at the surviving tanks till they are definitely put out of action. The remaining guns of batteries will meanwhile continue to engage the enemy's infantry either by barrage fire or by individual action as the situation may require.
"O.P.s must be established and manned near all batteries so that selected guns may receive immediate news of the approach of tanks; they will equally prove of value in observing fire against advancing infantry.
"It may occasionally prove possible to employ 60-pdrs. in this way; in any case 60-pdr. batteries must be prepared to engage tanks approaching their positions, the heavy shell of these guns being particularly effective against such targets."
37. "Ammunition.""All artillery specially detailed to engage tanks must use H.E. In the case of 13-pdrs. and 18-pdrs. No. 101 fuzes, with or without delay, should be used with H.E. against tanks, as with these guns No. 100 fuze (when available) cannot be relied upon to be effective in all cases. With all other guns and howitzers any type of fuze may be used."
38. Principles of Co-operation.The co-operation of trench mortars under all conditions is described in "Artillery Notes, No. 6Trench Mortars" (S.S. 139/6).
In the defensive battle the principal role of trench mortars is to relieve the artillery of as much of the close range work as possible.
Light mortars should be disposed in depth and their positions selected with a view to supporting immediate counter-attacks in the event of the enemy penetrating into any of our defences.
Medium (6-inch) and heavy trench mortars should, generally speaking, be employed on the same lines as medium and heavy howitzers, within the limits of their range; that is, for bombardment and for annihilating and barrage fire. Medium mortars, in particular, should also be utilized to bombard and barrage in conjunction with machine gun fire those parts of the enemy's trenches which are either too close to our own for artillery to engage with safety or for which for any other reason artillery barrage fire is not available.
Trench mortars should not, in principle, be sited within 500 yards of our front line, for in such positions they are liable to be put out of action by the enemy's preliminary bombard-ment and to be over-run in the event of the enemy succeeding in entering our lines. It may, however, be necessary to place a proportion of the available mortars in advanced positions in order that they may be able to bombard particular portions of the enemy's front system of trenches. Shell-proof emplacements and alternative positions should be provided, as far as time and labour admit.
The chief difficulty in all trench mortar work is the transport and storage of ammunition. This fact must be recognised, and special carrying parties are essential. The moving of medium and heavy mortars to new positions and the preparations for opening fire take up considerable time.
39. Gas Attacks.Enemy gas attacks may be executed for purposes other than the preparation of a subsequent infantry attack.
During a gas discharge from gas cylinders a heavy-artillery fire on the actual trenches whence the gas is issuing is the best way of dealing with the situation, provided, of course, that safety considerations admit. Also, it is essential that the gas discharge should be interfered with as early as possible, as the opening periods of the discharge are the most effective.
To ensure an effective and immediate artillery fire the following points require attention:
For some time past the tendency has been not to follow up a gas discharge with an assault. All the same, the artillery of the defense must be prepared instantly to open annihilating or barrage fire, as the situation may require.
40. Smoke Barrages.A smoke barrage may be employed by the enemy to cover an immediate attack, or it may be fired solely with the object of drawing our fire and thus disclosing the positions of our batteries.
The action of the artillery to be taken in such a contingency must therefore be carefully weighed, for the answers to these two probable reasons for a smoke barrage are directly opposed. The situation at the time must form the best guide. If there is reason to believe that an attack is imminent, annihilating fire should be opened at once, and its instant conversion to barrage fire must be possible. If, on the other hand, there is no reason to anticipate an attack, it will only be serving the enemy's purpose to disclose our artillery positions, and fire should be limited to an endeavour to arrest the smoke discharge by causing casualties to the personnel concerned. At the same time, all artillery should be immediately warned to stand by in case, after all, an attack should develop.
The action of hostile artillery and aircraft should ordinarily contribute to a decision as to the enemy's probable intentions.
41. Withdrawal of Batteries*It is a point of honour with batteries never to retire without orders from a position which they have been detailed to hold to the end. They must be prepared to defend their positions against close infantry attacks by means of their own fire and with the aid of such rifles and Lewis guns as they possess. Should it become apparent that guns will be captured by the enemy and when communication with higher authority is interrupted, artillery commanders must use their own discretion as to whether they will render more assistance to the defence by fighting to the last where they stand or by withdrawing to new positions where they can re-open fire under ordinary methods. In the latter case, retirement should be made by sections or half-batteries, the first echelon moving to an intermediate position whence the withdrawal of the rest of the battery to its selected position can be covered.
"When it is a question of ensuring the safe withdrawal of the main body, artillery must be ready to take any risk, and loss of material is then fully justified." (F.A.T., Chap. VII., Section 165.2.)
It is to be remembered that, in default of definite orders, the bold policy of holding a battery position to the last will generally pay. For by so doing the enemy's attack may be held up and time be afforded to the infantry of the defence to advance to the assistance of the guns.
Every battery sited for the defence of the Forward Zone must have positions allotted to it for the defence of the Battle and Rear Zones.
42. Disablement of Material.The destruction or disablement of material is only justifiable when it is apparent that guns must fall into the hands of the enemy. In view of the fact that it is always to be expected that a decisive counter-attack will restore the situation, it is rarely that resort should be had to the ultimate measure of destruction. Removal of breech-blocks will ordinarily suffice, at least for all guns that are situated in or behind the Battle Zone.
Instructions as to the methods to be employed for the destruction or disablement of ordnance are given in Appendix II.
43. The storage, transport and supply of ammunition is one of the most difficult problems that confront the successful handling of artillery in defence, and the solution can only lie in thorough forethought and most careful arrangements.
As regards storage, an adequate supply of ammunition must be kept at or near the guns, while a disposable reserve is maintained in Corps and Army dumps. Orders must be issued as to the amount of ammunition to be kept at reinforcing battery positions.
As far as labour and other practical considerations allow, shell proof cover should be afforded for ammunition, at least for cartridges. As a minimum demand, fixed ammunition and separate cartridges must be protected from the effects of the weather. All dumps must be concealed or camouflaged.
In all large gun and mortar dumps arrangements must be made so that one hostile shell shall not result in the explosion of a great part of the ammunition stored. Cartridges especially should be kept in small lots.
Touching transport and supply, it is most important that field tramways should, as far as possible, run right into (and beyond) the battery positions. Supply must be so arranged that by the aid of tramways, lorries and horse-drawn wagons, a continued interruption of traffic by the enemy's fire is impossible.
The control of ammunition at Corps and Army Dumps must be rigorously exercised, and officers in charge must be furnished with definite instructions as to what units they are to supply and their expected and actual consumption of ammunition.
The supply of ammunition to mobile reserves requires special attention, and a careful reconnaissance of the best and safest routes for this purpose is a primary necessity.