The Signal Service in the European War of 1914 to 1918 – Chapter 5

Jump to: navigation, search
«-- The Signal Service in the European War of 1914 to 1918
Chapter V
Chapter IV Chapter VI

Chapter V.


Lessons of the Battles of 1915. — Intensive Character of Warfare Causes Increased Precautions against Enemy Artillery Fire. — Buried Cable. — Laddered Cable. — Wire Netting. — Alternative Methods of Forward Signalling. — Visual. — Pigeons.— Wireless. — Lessons in Organization and Policy.

Although the main feature of Signal Service evolution during 1915 was undoubtedly the rise in the popularity of the telephone, numerous other lessons were learnt from the battles of this year.

On the front held by the British Force, the comparative peace of stationary warfare was interrupted by three main actions. Two of them — Neuve Chapelle in March, and Loos in September — were offensive operations on the part of the British Army, and at Loos the Cavalry Corps was massed behind our lines ready to exploit success should any considerable measure be achieved. In both cases, however, little advance was made and the position remained substantially unchanged. In the other battle which needs special consideration — the Second Battle of Ypres — the Germans once more concentrated their reserves in a sustained attempt to break through the British lines at the Ypres salient. Thanks to the employment of poison gas they were very nearly successful. Whole battalions of front line troops and supports were horribly asphyxiated and, but for the tenacity shown by the survivors, this second attack on Ypres might well have ended trench warfare in a sauve qui peut towards the coast.

This was not to be, however, and in the self-sacrificing stand without means of defence against this new and terrible weapon, the Signal Service played its part. All honour should be given to the runners who, despite the waves of suffocating gas, delivered the messages calling for reserves or artillery support to save a desperate situation. Equally splendid was the work of battalion and battery signallers and of the linemen and despatch riders of Brigades and Divisions. Until strength was exhausted and breathing no longer possible, they persevered at their tasks, only then to crawl away and die in agony, or, at the best, to be taken to the nearest Casualty Clearing Station and evacuated to the Base, there to cough and gasp away their lives with nothing but a consciousness of duty well done to sustain them in their agony.

No history of Signals nor of any other branch of the Army could be considered complete without some tribute paid to these men who, regardless of personal safety, stood fast at this most critical time. Later months brought with them various measures, more and more efficient as time went on, combating this and all other gases the enemy could bring into use. Almost at once the first "tube helmets" gave comparative immunity, but in these first days nothing saved the situation but sheer heroism displayed by infantry, artillery, and all other arms alike.

Before dealing in detail with the lessons learnt by the Signal Service in the battles of 1915, a short general discussion will not be out of place. In the story of the rise of the telephone system and its adaptation and improvement until efficiency was obtained, it was pointed out that the predisposing cause of this increase was the corresponding growth of the artillery. Throughout the year, as through succeeding years, war was becoming more intensive. Never before had armies had to face anything like the amount of shell fire which was now a daily feature of the enemy's prosecution of the war. Our own guns with their daily ration of a dozen shells or so could not compete. During battle, and notably during the actions mentioned earlier in the chapter, this normally heavy fire increased to an, as yet, unparalleled extent. It was not to be expected that the slender unprotected cables stretched across miles of country which were the frail connecting links between infantry and artillery, between front line and supports, between headquarters of units and formations, could survive the tornado to which they were exposed.

Multiplication of lines might give temporary immunity; the heroic work of devoted linemen might secure intermittent intercommunication; but one great lesson of position warfare was that line communication without an adequate and increasing amount of protection was unreliable in the extreme. More, it was too costly, for linemen's lives are not cheap and the skilled men necessary to deal with a system of increasing complexity cannot be replaced at will. This lesson was taken to heart at once. After a little time attempts were made to solve the problem. The Buried Cable System of 1916 was the final answer which with various small modifications outlasted the war.

This lesson had, however, an important corollary. There was no prospect of a shell-proof system being built immediately. Indeed, a good system must take weeks to evolve and months to build. In the meantime something must be done to supplement line communication at once. Here was an intricate problem for solution. Visual was already discredited; Army Wireless was in its infancy; the runner, though reliable, was slow and far too costly. Where was the answer to be found? The problem was only solved by the development of all these methods to suit new conditions, and by the formation of a Carrier Pigeon Service. Thus the second great lesson of the battles of 1915 was the development of supplementary means of communication. No longer would the Signal Service carry all its eggs in one basket. During 1915 itself, and during the early months of 1916 — until the Battles of the Somme gave opportunity of putting all these means into practice in a great offensive — every effort was devoted towards the evolution of practical systems of trench wireless, trench visual, and, last but not least, an efficient carrier pigeon service for forward work. This year may be characterized as the year of evolution of new methods of signalling; next year was to see the co-ordination of the various means in centrally-controlled and well-advertised schemes.

The culmination of this particular branch of Signal Service activity may be seen in the formulation of a general policy of forward signal work which was finally crystallized and set down in "S.S. 148." The publication of this manual marked a great step forward in Signal Service progress and will be further considered in its place.

Finally, the trying times through which the Signal Service was now passing were, as already indicated, not without result of another kind. Co-operation was first imposed on Signal units by the mushroom-like growth of the telephone system. The comparative failures of Signals in 1915 forced signal officers in self-defence to combine to make the most of their very limited resources. The vagaries of particular formation staffs gave birth to a need for sympathy and for knowledge of what was happening in the adjacent formations. Similarly, the hope of help from above made the O. i/c Signals of the lower formation more inclined to look for assistance to his colleague at the Corps or Army behind him. All these things combined together for good, and out of the many difficulties and distresses of the present arose the future organization which gave to the signal officers of rear formations senior rank and a greater power of supervising, guiding and formulating forward signals. All this was to the benefit of the Signal Service.

A general summary of the lessons learned from the 1915 fighting thus shows three main ways in which the evolution of signal practice and organization was most marked. It is now time to consider them one by one and review their history in detail.

From the beginning of the war the vulnerability of airline and field cable to intensive shell fire was forced upon the attention of everyone concerned. Various methods were tried to overcome this very serious difficulty in the way of maintaining line communication, but for some time with little success. The first step following the exposure of the relative vulnerability of open wire routes was a considerable extension of the use of cable in the forward areas. It was then discovered that cable slung lightly on poles was much less vulnerable than ground cable to high explosive shells bursting on impact. The former was, therefore, substituted for the latter where-ever possible. The next improvement was the adoption of "trench" cable and this at once caused certain modifications in the use made of the various types of cable in the forward area. The enamelled wire and "D1" issued to infantry and forward artillery units served well enough for short periods of time over dry ground or slung on hedges. Their insulation was not, however, intended for trench work, and gradually, as the wet weather set in, both were almost entirely replaced by "D5" even in the front line trenches. This meant, of course, the issue to infantry of lengths of "D5" cable to carry out repairs to the lines which were in their maintenance areas, and the use of the lighter cables fell into abeyance to a certain extent. It is, indeed, interesting to note that enamelled wire never regained any measure of popularity. When broken, it was just as difficult to mend as "D1" or "D2" cable. It was easily damaged by traffic and was particularly cable to such breaks owing to its comparative invisibility. Once the break had occurred, also, the stiff wire ends sprang away and were only retrieved with difficulty, and sometimes after long search.

The next improvement in the line system was the duplication or triplication of lines with the idea of obtaining alternative circuits. In the case of some Brigades operating over heavily-shelled country, as many as six different lines were laid between Brigade and battalion headquarters. These were bunched where they entered the shelter of the trenches and bunched again in the more sheltered areas further to the rear, but spread out by different routes where they passed the more exposed intermediate zone. This policy was attended with a certain measure of success, but was only a palliative. It was also exceedingly wasteful of cable at a time when the supply of cable was very scarce and its economical use all-important.

By the early spring of 1915, however, experiments were already being made with buried "D5" cable, and in this connection it is interesting to note that the first efforts recorded were directed against damage to the lines by traffic rather than shell-fire. This was a natural sequence to the use of buried cable at gate-crossings and gaps of all kinds where traffic was likely to cross the line, which had long been an established feature of the cable wagon drill. The first extension of the use of such local buried crossings was the burying of cable routes along the edges of aerodromes in Flanders.

As early as the month of January, 1915, a further extension of the use of buried cable occurred between a Brigade headquarters and the Keep at Givenchy which was held by one of its battalions. This strong point was expected to be able to hold out for some considerable time, even if the surrounding trench system was overrun by the enemy and it was considered advisable to have a secret means of communication with the garrison. Experiments with trench wireless were yet to begin. Visual as then practised could not by any stretch of imagination be considered secret. There remained the possibility of constructing a line which could be securely hidden. With this in view a "D5" cable was buried between the two headquarters in a trench 18 ins. deep. About the same time, the laying of traffic-, splinter-, and shrapnel-proof cable in trenches up to 30 ins. deep was tried in several British Divisions. The advantages of the new system at once became so obvious that this method of protecting lines was persisted in in face of the labour difficulties which were always its greatest enemy. No special labour could be allotted for the purpose. At first, the work was carried out by the Signal Company personnel themselves, but it soon became quite clear that these men, already overworked, could not deal with a buried system on anything like the scale required. The next advance was the employment of small parties of 10 or 20 general duty pioneers from the Engineers. In some Corps, even, small labour parties of Belgian civilians were recruited and these men were paid contract prices, the adults receiving three francs for a working day of ten hours and boys from two to 1-1/2 francs according to their strength.

By this means and that, it proved possible to dig the first few experimental cable trenches, but the conspicuous success attending them soon caused the desire for buried cable to become universal. The use of shrapnel was much more general in those days than high explosive. The new trenched cable was not immune from a direct hit by a high explosive shell, but shrapnel, traffic, and even shell splinters, were powerless against it. Time after time, a few minutes after operations had commenced, the one or two "D5" cables in filled-in trenches were the only survivals of a complicated system.

Buried cable had established its right to existence even at some inconvenience and at the cost of considerable labour. Somehow this labour must be forthcoming. The problem was finally solved by the system — exceedingly unpopular with the victims — of employing large parties of infantry in rest to dig and fill in the various trenches required. Before the end of the summer of 1915, the dangerous zone between the rearmost communication trenches and the advanced Brigade headquarters was usually bridged by one or more cables buried to a depth of 2ft. 6in., and on many occasions these buried cables remained through when all other fine communication had long been shot away and could not be replaced.

From the first, one of the main problems presented by the new method of using cable was the water-logged condition of the ground where buried cable was first brought into use. In particular, the district around Ypres, where shell-fire during the Second Battle of Ypres first caused the general use of buried cable as a system, was very wet, and only the best "D5" cable could be used with safety. The latter cable, however, did yeoman service under the new conditions for which it was never intended. Month after month, circuits which were not blown to pieces by direct hits kept through, and in some cases these early buried lines remained in working order well into the next year. In the wet and muddy soil near Ypres they were buried a good 3ft. before they could be considered even moderately safe from shells. It was indeed surprising how well the insulation of the lines lasted under the most severe conditions of test. Perhaps the greatest innovation took place when similar "D5" cable was laid through the water of Zillebeke Lake. Prophecies of its immediate failure were many, but all were falsified. The great difficulty proved to be — not the loss of insulation — but the many breakages which took place near the edge of the lake, where the depth of water was not sufficient to protect the cable either from shrapnel or from splinters. It was here cut again and again and the submerged end could only be recovered after long search with improvised grapnels. This finally caused the diversion of this portion of the cable round the edge of the lake, but the experience of the resistant nature of the insulation of "D5" was very reassuring and led to its more general use in similar situations.[1]

Many methods of guarding the cable against the wet and at the same time of giving it additional protection from mechanical strain were tried, but were not usually found worth while. Rubber tubing was used with fair success at ditch and stream crossings; many lengths of cable were laid in gas piping to prevent direct contact between the cable and the soil; in yet other cases iron piping of 1 in. bore was used. In the long run, however, it was found advisable to rely on the "D5" cable, carefully laid in a trench with a level bottom, and to use this until its insulation failed, or until it had been shattered and repaired so often that it was necessary to relay the whole or portions of the line.

Towards the end of the year various improvements had been tried and the systems generally had been more or less standardized. The main features were, however, still the 2ft. 6in. buries between the rearward limit of the zone of frequent shelling and the nearest communication trenches or battalion headquarters. Routes had become more common and many Brigades and Divisions holding particularly exposed fronts such as those in the Salient had duplicated or even triplicated their main buries. In one or two formations, a four-horsed plough had been used successfully as a labour-saving device and this led to exhaustive experiments which will be referred to later in describing the 1916 Buried System. Already several lines were being laid in the same bury, as the policy of concentration of lines was steadily carried out. There was, however, a limit to this concentration. Earthed lines were still in general use and induction troubles were very marked on the early multiple buried routes. Some times during operations one line only in each bury could be used. If more were employed, over-hearing and consequent irritation and inefficiency far outweighed the advantage of being able to carry on two conversations at once. The use of twisted pairs was indicated and was already a matter of general discussion. For the present, however, the shortage of cable was too acute to allow this solution of the difficulty to be adopted. It was reserved for the more serious question of enemy overhearing to sweep away the prejudice against metallic circuits. In individual cases signal officers took the matter into their own hands, and twisted "D3," sometimes, even, improvised twisted "D5," was laid and buried, but as a general rule earthed lines were persisted in, in spite of induction troubles.

A special variety of buried cable which should receive passing notice was that laid in the forward trenches. Even these did not give sufficient protection against shrapnel, bullets and splinters, and especially against traffic. Buried cable soon spread beyond its original forward limit and many lines were buried 6 ins. below the bottom corner of the trenches. This custom did not gain general popularity, however. It is true the lines were safer, but the difficulty of maintenance was also much increased. Trench cables such as those described in the last chapter were much preferred and buried cable in trenches was never universally adopted.[2]

Before finally leaving this description of the earlier buried cables, mention should be made of the first proposal for the introduction of armoured cables. This was made in the autumn of 1915. The use of these cables did not actually become general until the following year and they are better considered in detail when describing the evolution of the "deep" bury. They first sprang into prominence, however, in this autumn, when at a conference of signal officers of one of the armies they were referred to as the "only possible solution of the present complicated forward trench System." In isolated cases they had been used in buried cable routes before the year was out and it soon became evident that the only obstacle to their general adoption was that of supply.

Not the least of the problems raised by the general adoption of the shallow bury was that of the identification of the routes. Trampled upon by traffic of every description, used as a guide by all ranks returning to and from the trenches, the neat rounded mound which marked the site of the newly-buried cable was soon levelled with the surrounding country and reduced to the semblance of the numerous tracks that covered the war-worn country in an intricate network. Time after time, the earlier buries were lost to all intents and purposes and it was soon evident that some means of marking buried cable routes clearly and definitely was urgently required. Here, as in many similar cases, unexpected difficulties arose. The neat stakes or standards with their carefully-painted blue and white squares were trampled under foot or torn up and burnt by cold and hungry soldiers. The final solution of the difficulty came with the introduction at a later date of special metal buried cable "markers," but a temporary remedy was early found in at least one Corps in the Ypres district. Despairing of the ordinary stake marker which was erected only to be used by the private soldier for his own illegitimate purposes, an ingenious subaltern hit upon the idea of marking his buries with a series of wooden crosses with the inscription R.I.P. He had chosen the one emblem the British soldier will respect himself and will not allow any other man to abuse. From the date of the erection of the new emblems, his lines were labelled for the duration of their usefulness, and the incident is a striking example of the ingenuity necessary to keep ahead of circumstances. Much of the thought expended by officers and men of the Signal Service during the war was devoted to overcoming the obstacles put in their way by the mass of the soldiery whose needs they were serving. This is a factor which will recur in future wars, unless a campaign of education is carried on among the rank and file of the troops — both Regular and Territorial — in time of peace. Instances will arise in this History again and again of special efforts directed towards the education of the rank and file in the uses and limitations of signalling in war, or of special organization or devices to combat the results of an ignorance which was as dangerous as it was universal. The blame for this in the past cannot, perhaps, be accurately apportioned. It is for the Signal Service of the future, with its vastly greater powers and responsibilities, to see that efficient propaganda is carried on and that the situation does not recur. Had the energy expended on policing circuits, on tracing routes lost through the wanton removal of the means of identification, and on repeating work wilfully destroyed, been available for improvement of the existing system, better results cannot but have been obtained.

A special aspect of the protection of the line system against enemy artillery fire was that which arose in the very forward and exposed areas where the trench system was incomplete or even entirely wanting. This was particularly the case after an advance or a reverse. In either case the infantry, having left their original defence system which had been made good by many months' work, were compelled to dig themselves hastily into little unconnected strips of trench or into individual rifle pits. Some system of signal communication between the principal posts and headquarters had to be devised, and this difficulty was overcome to some extent by the use of "laddered" cable. Two lines were laid from front to rear with an interval of the order of 60 yards between them. These were then cross-connected by a number of lateral lines, the resulting network resembling the uprights and rungs of a ladder. Such a device minimized the likelihood of a complete disconnection, although individual breaks were more difficult to locate. Laddered cable was very useful during and immediately after an advance or a retreat, and became at one time very generally used. The main drawback to its use was the necessity for constant overhaul of the whole network in order to ensure efficiency. If this was not done systematically, weak places would accumulate, until a final break might render the line useless.

A local variant used in some formations was rabbit netting. This was often experimented with, its value being that it was more difficult to cut than cable. Lengths were laid with six inch overlapping joints, connected by copper wire, but not soldered. The netting was tried both suspended on stakes and lying on the ground, and good buzzer signals were obtained over distances up to 1000 yards. It was very cumbersome, however, and by no means immune from the effects of high explosive shells. Although frequently employed near heavily-shelled spots such as cross-roads, it never gained a prominent place in the scheme of forward communication.


It is now necessary to consider the second great lesson of the battles of 1915 — the necessity for supplementary means of communication to reinforce the telephone system. This need was driven home — also by the German artillery — both in attack and defence. Did the enemy attack, then his attack was preceded and accompanied by such a barrage of shells that all line communication became uncertain and, in many cases, the life of the forward lines could be measured in minutes. Did the attack come from the British lines, it was invariably countered by heavy enemy shelling on the whole forward area, both that occupied before, and that captured during the battle. In all cases, the persistence of line communication as far forward as battalion headquarters was the exception rather than the rule.

Late in the year, the general adoption of the splinter-proof bury eased the situation, but even that was not infallible and when broken took some time to mend. In the meantime the great need was for some means of communication which depended for its safety and usefulness on some other factor than the continued maintenance of an uninterrupted thread between headquarters. Good work was being done in battle by the lines to the rear of Division, and also between Division and Brigade. In the Ypres fighting, telegraphed messages between Army and Division averaged 15 minutes, while exceptionally good times ranging between six and eight minutes were not uncommon; D.R.'s over the same distance taking from 1/2 to 1-1/4 hours.

It was in the forward area — in the zone of frequent shelling — where the disconnections were most common and continuous, and it was here that supplementary means of signal communication were most needed. Whether the matter in hand was the relief of our own hard-pressed troops, reeling back before the waves of German gas and battered beneath a hail of shells; or whether the problem was to bridge the gaps between our own advancing troops and battalion and Brigade headquarters, signal touch could not be maintained with lines. Constantly shifting their targets as the situation changed, the German artillery thrashed the contested area continuously with an iron storm. Lines laid before the attack were blown to pieces before they could be used. Further attempts to establish line communication resulted in casualty and failure. Again and again would front line troops be isolated for hours, and sometimes even for days. Driven by sheer necessity, battalion commanders and Brigade signal officers alike began to have recourse again to visual. Flags were sometimes used from sheltered sites in buildings and copses without attracting the enemy's attention. Discs and shutters, as inconspicuous and small as could be usefully employed over the distances involved, were designed and manufactured in large numbers, issued to front line troops, and used by them on occasion with great success. Exposure of the receiving station was minimized by the introduction of the trench periscope; its safety was catered for by the building of heavily-concreted emplacements or the use of specially strengthened buildings. In this respect, evolution was parallel with that which was taking place in the line system simultaneously with the introduction of buried cable. Central test stations and central visual stations were planned on similar lines, though usually the same building or shelter was not used for both purposes. This could not well be, for one of the first principles of the new school of thought as regards line routes was that they should avoid all prominent features of the landscape. Test stations in particular were to be as inconspicuous as possible, reliance being placed rather upon freedom from enemy observation than on protection once attention had been attracted. Fortification as applied to trench warfare was yet in its infancy and the occupants of the new central visual observing posts were in no enviable position. Few shelters yet existed which would stand the direct hit of any but the smallest types of high explosive shell. Visual stations were necessarily in exposed positions, though in the worst cases attraction of undesirable attention was minimized by the adoption of D.D.D.D. working. Any prominent point was. however, a natural target for artillery, and many casualties testified to the devotion shown by the Divisional, Brigade, and battalion signallers whose efforts made possible the rejuvenation of visual.

A modification of the use of the disc was afforded by the issue of discs on long poles intended for use from the comparative shelter of forward trenches. These were, however, not an unqualified success. They were a considerable encumbrance to the regimental signaller, laden as he already was with his full infantry equipment, and in many cases they did not reach their destination. In later types this difficulty was overcome to some extent by adapting the disc to fit on to the signaller's rifle. Always, the powers of endurance of the men had to be taken into consideration. So often the various new devices for forward signalling in an attack — excellent as many of them were — proved to be the proverbial last straw to break the camel's back. At the ordinary steady pace of an advance, the signaller could just stagger along with all his various impedimenta. If, however, anything out of the ordinary happened, if special haste were required of him, or if he became involved in the vagaries of a bursting shell there was the chance that his signalling apparatus would be the first thing to be dropped. Not once nor twice, but many times, signalling parties arrived at their destination only to find themselves useless owing to the loss of some essential piece of apparatus. Discs and shutters are only a case in point. Later, with the introduction of more complicated means of forward signalling, this factor assumed a more important aspect. For the present it may be noted as the most prominent cause of the failure of the long-handled signalling discs from which much was expected by their sponsors.

The rise of the signalling disc in popularity was admittedly the feature of the new visual telegraphy by day. Semaphore with the necessary exposure of the person was still unpopular save under exceptionally favourable circumstances. Morse on the flag was also relegated to a subordinate position. The daylight lamp was yet a thing of the future, though the germ of the idea was already forming in minds ever searching after new expedients. For night work, the old Begbie lamp had proved itself hopeless. Both by sight and by sound, even — so said some signallers — by smell, its presence betrayed itself to all enemy posts in its immediate neighbourhood. Its place was now definitely taken by the much more portable and much more silent electric signalling lamp, the first pattern generally adopted being that used in the French Army.

The large degree of dispersion of the rays of this lamp was still a decided drawback in the eyes of forward signal personnel. Still more was this so in the eyes of their neighbours, who, without a personal interest in the signalling lamps, were exposed to the full effects of the storm of shot and shell so frequently brought down upon the vicinity of visual stations by their too incautious employment. This matter was also taken in hand in 1915 with good effect, however, and excellent results were obtained over distances up to half or three quarters of a mile by the use of tubes 1 in. or 2 ins. in diameter, which reduced the dispersion of the signalling beam. With the rays directed and controlled in this manner, two-way working was possible, even with one station within a hundred yards or less of the front line. Horizontal and vertical dispersion were both reduced to a very few yards over the distances covered. To make assurance doubly sure it was only necessary to see that the lamp at the rear station was aligned so that its rays projected slightly downwards. There was then no likelihood of a distant German station picking up its light. This artifice proved successful and was very generally adopted in forward stations both for one-way and for two-way working. The use of these tubes demanded considerable skill and care both in the original alignment of the station and in the subsequent working, but keen men soon reduced the setting-up and working of the new visual stations to a routine.

Once more the front at night was starred with minute winking flashes of light as the Morse messages passed to and fro, the only difference being that from now on each station had its own particular star jealously screened from all alien observers. Indiscretion or bad management had an altogether disproportionate penalty. A lapse, no matter how slight, might result in summary extinction. At the least it was likely to be visited on the head of the offender in the form of the wrath of the nearest Brigadier. Many a signaller would have found it difficult to say at short notice which he would have preferred. In both cases, the result was the same. Slips were seldom made and gradually visual regained a certain usefulness and popularity.

Thus, in one way, the yawning gap between front line and artillery and supports, and between advancing troops and directing Staff, was bridged without the intervention of lines. The weakness of visual was that it was never of universal application. Beyond every other method of signalling, it is dependent on favourable weather conditions. The mists of early dawn — the usual hour for attack on either side — were fatal to its use. The "fog of war" was another obstacle which was inseparable from the conditions under which supplementary signal communications were most essential. The smoke and dust of bombardment were fated time and again to cause the entry in the reports of signal officers of the words "Visual impossible." It was quite clear that visual schemes, useful as they sometimes were, could only be a partial solution of the problem of replacing an unreliable line system.

Some other means was required — if possible one independent of weather conditions. The problem was to do away with wires. One inevitable answer was "Use wireless telegraphy," but in the path of the adoption of this solution stood many obstacles. Wireless telegraphy was yet in its infancy and many months of experiment would be required before decisive results could be hoped for. In no army had wireless yet been adapted for trench work. Use could not be made of work already carried out by our allies; deductions could not be drawn from progress made by our foes. Our own Intelligence informed us that in neither army were small wireless sets in use for tactical purposes. The nearest approach to what was wanted existed in the British Flying Corps and it was along the lines of these sets that the first experiments were carried out.

In the summer of 1915 the problem was tackled in earnest, and officers were definitely appointed to carry out experiments in trench wireless. Thus the first step was taken in the programme that was destined to rejuvenate wireless, converting it in time from a temporarily obsolescent type of intercommunication, into one of the mainstays of the signal system, as it became during the advance in 1918 and on the Rhine in 1919. This result was not achieved in a day. The struggles of forward wireless for recognition — first as a possible means of intercommunication in emergency, then as a regular means of supplementing line communication, and finally as an efficient means, under certain circumstances, of replacing lines — form no mean part of the history of the Signal Service from this time onwards.

It was at once evident that it was worth while to endeavour to produce stations suitable for work as far back as Corps headquarters. Already the range of the enemy's guns was encroaching upon the hitherto inviolate territory behind Divisional headquarters. In this year Bethune was shelled with 15-inch shells and soon afterwards these projectiles became a recognized feature of back area shelling. It did not need much prescience to foresee a considerable rearward extension in the immediate future of the zone affected by enemy shelling. An additional argument in favour of Corps stations was the necessity for control which would at once spring up with the general adoption of small range wireless sets. Behind Corps headquarters, the sets already in existence, with perhaps slight modification, would suffice. The Marconi 1/2 kw.[3] pack set might even conceivably be of use forward of Corps headquarters, but the ranges for which this set was intended were considerably greater than the distances over which it would have to work under the new conditions. Excess of power was to be deprecated for several reasons. For one thing, universal jamming[4] might be expected to result; for another, any undue use of power would assist enemy wireless stations in their work of intercepting our messages.

For both these reasons the pack wireless set was ruled out for general forward work, though used for the early experiments. The men engaged in building up the new system were given the task of designing two suitable sets; one for use near the front line or at Brigade or Divisional headquarters, the other slightly more powerful, for use as a directing station with the Corps.

Meanwhile the first experiments in the line were actually commenced with Stirling transmitters and short wave receivers borrowed from the R.F.C. On June 15th to 17th, 1915, four of these sets were erected at the headquarters of two divisions, one brigade, and one battalion of the V Corps. A series of exhaustive tests were carried out and the value of the new short range wireless as an emergency method of communication was at once demonstrated. In these early experiments the directing station was a lorry set specially adapted for short wave working, but it was from the first obvious that this must be only a temporary expedient and that as soon as possible it must be replaced by a more portable and less conspicuous set. A rough sketch of the position of the sets and of the type of aerial employed with the set at Ypres is shown in Plate IX. Although not on this occasion used for messages of tactical importance, touch was successfully maintained under adverse conditions and the possibilities of the new application of wireless were fully demonstrated.

The experiments were continued and obstacles to progress were steadily overcome. At the same time a fresh use for wireless was suggested — that of direct wireless communication between observation posts and the headquarters of batteries or brigades of heavy artillery. This problem was a similar one in its essential features and its solution was attempted along the same lines. R.E. personnel could not be spared, but Signal Service instructors and some small sets were provided for the brigade chosen for the experiment, and N.C.O.'s and men of the artillery were collected in a class and trained in the principles of wireless telegraphy and in the use of the small portable wireless sets. This experiment was even more successful than the former one and from the first the sets were used for observation purposes. Their value was demonstrated almost the first day of their arrival when enemy shelling destroyed six out of the seven cables running to one of the observation posts, and four men were wounded or killed in carrying out the necessary repairs to the lines. The small wireless aerial did not escape attention. It was shot away again and again, but was easily replaced in the lulls of firing, and was maintained throughout the "shoot" without loss of effectives.

By the middle of August a design had been drawn out for a suitable wireless set for forward work. It was sent home together with an experienced technical officer who had been personally engaged on the problem, and the building of 100 sets to this design was ordered. It was this set slightly modified which finally took its place, as the B.F. set, in the standard equipment of all Divisional signal companies. The cryptic letters of the name round which much speculation on the part of the uninitiated has centred, refer essentially to the main purpose for which the set was intended. It was designed for use by hurriedly trained operators and was therefore to be as nearly as possible "fool-proof." Hence, by the Army generally, with its tendency to provide nicknames for everything and everybody, the letters B.F., given as an appropriate title to the set by its designer, were acclaimed as being an ideal appellation. The new instrument was known as the B.F. set to all within whose range of experience it came, and the title by which one was accustomed to refer to it when describing it to Generals at official inspections — the British Field Set — was in part devised to cast the mantle of respectability over the original meaning of the letters. Well-conceived for the work for which it was intended, the station could be successfully worked by the most inexperienced wireless operator, and with its general adoption much later in the war the early troubles of forward wireless were much reduced.

In the early days of experiment the set was not produced in sufficient numbers to stand alone. Many others shared the field for some time and chief among these was the Stirling transmitter and the R.F.C. type of short wave receiver.

These latter, however, uncombined as they were, required a party of five men to transport them. The bigger the party required, the less likely was it that the whole of it would arrive at its destination, while there was also a greater waste of personnel for a given amount of result achieved. The new British field set was a combined receiver and transmitter, stoutly built and designed to stand the conditions, of forward work, and it soon outdistanced all rivals.

While the development of a suitable wireless set for forward work was being made the subject of experiment, search was being made for a set of slightly greater power, and yet with as high a degree of portability as possible, for use as a directing station at or about Corps headquarters. This was very quickly solved by the discovery of the possibilities of the Wilson wireless transmitter combined with the Mark III service short wave receiver. With a mast 30 ft. high — quite a possible height under the circumstances in which the set would be used — good signals were obtained both ways between this set and the new B.F. set at a range of 10 miles.[5] The Wilson set possessed a very musical note and a satisfactory degree of simplicity and strength, and was probably the most successful of all the spark wireless sets produced during the war. It at once replaced the pack set as a directing station and, with the B.F. set, was destined to become the standard apparatus for forward wireless working in the area between Corps and Brigade headquarters for the duration of the war.

During the first experiments much trouble was experienced with the R.F.C. wireless sets working to the artillery. The latter possessed an almost complete monopoly of wireless working on short wave lengths during the early months of this year, and, not unnaturally, were jealous of any infringement of their rights. In the first trench wireless experiments their own type of sets was in use and complaints of jamming were numerous from both sides. The tactical significance of trench wireless was not yet quite clear and at first the new stations laboured under considerable disadvantages, their working being suspended on several occasions while special shoots and reconnaissances were carried out. Both sides were, however, amenable to reason and a compromise was soon effected, the R.F.C. retaining complete control over wave lengths up to 300 metres and the new army wireless sets being standardized on 350, 450 and 550 metres. From this time, jamming troubles with our own sets were less acute, though the situation was soon to be complicated by the arrival on the scene of action of German trench sets of much greater power than our own, and by the enemy's employment of special jamming stations.

It was at the Battle of Loos in September, 1915, that the tactical employment of the short range wireless stations was first justified in action. For this operation a wireless section consisting of two lorry sets, two pack sets, and six short range sets was attached to First Army under a specially-qualified senior officer. Previous to the battle, one pack set was installed in a dug-out on the Bethune-Lens road near Vermelles, and the short range sets — to man which a considerable proportion of the personnel of the motor lorry section was absorbed — were arranged to provide emergency communication between each of four divisions and one of their brigades in the line. The dispositions of the sets were altered from time to time during the battle and one set in particular was erected in Loos after its capture and did most excellent work in spite of heavy shelling by shrapnel and high explosive shells. In a general summary like the present, it is not possible to go into the details of the action, but on three critical occasions wireless messages were got through when all other means of communication had failed. On one occasion, the cavalry would have been ordered forward under the impression that the enemy's line was pierced and must infallibly have suffered heavy casualties but for a message from the small wireless set in Loos. On a second, the troops in Loos were hard-pressed and wished to withdraw. They would have done so, and Loos would have been lost, had not a wireless message been received advising the immediate advent of support. In the third case, casualties were occurring among our own troops from our own artillery fire. All means of signal communication had failed except wireless, but by this means the error was corrected and the fire of the guns directed on to enemy targets. Many minor administrative difficulties were betrayed by this operation and the correction of these was put in hand at once. A far greater obstacle to the use of trench wireless was, however, not so susceptible of immediate improvement. There was a general disinclination to use it even though it had already proved its value. Commanding officers considered that wireless was likely to give their positions away; Staffs thought the code that had been arranged for the occasion inadequate and cipher troublesome; Signal Officers themselves had little faith in the value of the new method of signalling. Once again the Signal Service, and in particular the officers detailed to promote the use of wireless, were faced with difficulties which could only be surmounted by a campaign of education and propaganda. This was at once commenced. The history of trench wireless during the following year is largely the attempt to popularize this means of signalling both within the Signal Service itself, and amongst the Staffs and Commanders who would have to use it as a means of transmitting orders and information. It was a long uphill struggle and was complicated by the occurrence of the many technical failures which are inseparable from the building up of a complicated organization and the use of delicate instruments under war conditions. It was not until 1918 that forward wireless really came into its own, though both in 1916 and 1917 individual cases occurred when wireless proved the only survival of a shattered intercommunication system. Such cases properly advertised converted many officers from hostility to warm partisanship. The education of the Signal Service itself was carried out by means of classes of junior and senior officers, held first at the wireless headquarters at Campagne les Hesdin and later at the Wireless School at Abbeville. Every wireless officer was an enthusiastic teacher, preacher, and prophet. As we go on to consider other phases of the growth of Signals, we can leave the wireless service carrying on with its experiments, its schemes, and its educational programme. The organization through which this new branch of signal activity was controlled and manned will be reviewed in some detail in a later chapter.


The natural rival to visual and wireless for bridging the forward zone where wires were difficult or impossible to maintain was the pigeon. In a previous chapter the use of pigeons by the Intelligence Corps in the early months of the war has been referred to. It was in the spring of 1915 that the attention of Corps and Divisions was first attracted to the possibilities of this method of conveying messages. In May, during the enemy attack at Ypres, pigeons were successfully used to bring back situation reports and requests for assistance and artillery support, and it was as the result of these operations that the first Corps Pigeon Service was organized in the Second Corps in that month.

From this date the growth of the forward Carrier Pigeon Service organization was rapid. The obstacles in its way were considerably less than those which hindered the advance of trench wireless. The carrier pigeon had long been recognized as a trustworthy and speedy means of conveying messages over distances far greater than those involved in the new experiment. The birds had no great objection to shell fire; they were much less susceptible to the effects of poison gas than human beings. The chance of their being hit whilst on the wing was very small, and if hit while in the trenches they were much more easily replaced than the runners instead of whom they were being used. One disadvantage of their use was the fact that the lofts had to be kept well back out of sight of the enemy and out of range of his guns. This meant of course the abandonment of the ordinary channels of communication, and pigeon messages went straight from battalion headquarters or from pigeon posts in the trenches to Division or Corps headquarters. As the majority of the messages were intended for the Brigade to which the battalion belonged, a certain amount of delay was inevitable. It was, however, reduced to a minimum by connecting up the lofts to the nearest signal offices of the formation which the birds served. Messages were treated as priority and were given preference over all less important telephone traffic. Thus a message from the trenches could be relied upon to reach Brigade headquarters in 10, 15 or 20 minutes, according to the distance flown by the birds. In addition, the barraged zone was traversed in minimum time with minimum loss of life, and as a result pigeons increased rapidly in popularity amongst the front line troops.

One trouble which had, of course, to be faced from the outset was the human element in the problem. Men were carefully trained in pigeon duties. Stringent regulations were made as to the feeding and watering and the general care of the birds, but here again careful education was necessary to avoid wastage both of birds and of opportunities to use them.

It was very difficult at first to prevent the infantry making pets of their birds, feeding them at odd times and on forbidden food, and in other ways making them disinclined to leave their baskets in the trenches. The limitations of the pigeon were also not at first understood, and many messages were rendered of no avail through birds being liberated in the dark or too late to enable them to reach home before darkness fell. Similarly, if cocks and hens were liberated together, the result, while it might ultimately increase the numerical strength of the pigeon service, was not liable to improve the time of the individual message concerned. Pigeon nature altogether is not unlike human nature, and the natural habits and desires of the birds had to be taken into account so far as was possible. As more and more men were trained as brigade and battalion pigeoneers, a greater degree of efficiency was attained. Pigeons were properly handled, properly fed, protected against the rats, which were their natural enemies in the trenches, and against wet and mud. The care of pigeons became as natural to the men entrusted with them as horse mastership is to the men of a mounted unit. Whenever possible, men with previous experience of the birds were chosen , but whether this was so or not there was no difficulty in obtaining a sufficiency of enthusiastic volunteers. As the service became more efficient, a greater proportion of birds homed successfully and in better time and, by the autumn of 1915, the carrier pigeon had become a usual and most valuable supplementary method of communication.

The organization of the first Corps service included the allotment of certain lofts to the Corps and the formation of a pigeon station for each Brigade sector of the front. At each Brigade station was a basket containing four pigeons in charge of a specially trained man. Two copies of the same message were usually sent off by different birds to avoid possibility of miscarriage and the time of flight from all stations averaged about 15 minutes. At the loft, an ingenious arrangement was contrived, by which the pigeon landing in the trap automatically rang an electric bell which served the purpose of notifying the loft attendant of the bird's return and in some cases of calling up the local signal office. On receipt of this warning, a D.R. at once proceeded to the loft and brought back the message. This was then handed in at Corps headquarters, a copy being wired simultaneously to the Division and Brigade concerned.

The extension of the Carrier Pigeon Service for general signal purposes was very quick and widespread in the summer of 1915, and G.H.Q. Intelligence at once realized the danger and inconvenience of divided control. In June of this year the proposal was definitely made that the Director of Signals should assume complete control over a remodelled service and without any further delay the reorganization took place. It is impossible here to go into the detail of this reorganization, but in principle it provided for a Carrier Pigeon Service centrally controlled from G.H.Q. and catering for the establishment of ten pigeon stations with each army and a similar number with the Cavalry Corps. A considerable number of extra men was required to man the new service and the enlistment of 60 specialists was sanctioned. The question of the immediate supervision of the service was overcome by transferring to the Signal Service the officer who had organized the Carrier Pigeon Service for the Intelligence Corps. He was now made responsible to the Director of Signals for the efficiency of the new Signal Carrier Pigeon Service. The original estimate of ten carrier pigeon stations per Army was soon exceeded and First Army organization towards the end of 1915 is seen in Plate X. During the battle of Loos when trench wireless first underwent extensive trial, pigeons were also employed, and to a more considerable extent. During the fortnight that followed the commencement of the offensive many urgent messages were transmitted by pigeons. Casualties were few, 14 birds in all being lost, and times were very good. A slight reform which had good results was the invention of a smoke bag to protect pigeons from gas while in their baskets. This was made on the same principle as the smoke helmet and was very successful, birds being kept in gassed areas for as much as six hours without bad results.


So far, in the present chapter, the protection of cable routes in forward areas and their reinforcement by other means of signalling have been considered. An equally important step forward in the evolution of the Signal Service is seen in the general consolidation of its policy and its members and the building up of an esprit de corps under pressure of circumstances. The original signal units which landed in France in 1914 were uncoordinated. No senior officer commanding a company owed allegiance to anyone except his Staff and — in very much less degree — to the Director of Signals at G.H.Q. Attempts of the signal officers of higher formations to assume control over the Signals of lower formations would have been resented and co-operation generally was at a minimum. As time passed and the pressure of circumstances increased, the first result was a certain interdependence between units. With formations constantly shifting about in the line, Os.C. Signal Companies were constantly coming into contact with one another, exchanging ideas, and modifying points of view based merely on their own experience. Systems admirably adapted for one part of the front were not suitable for another. The open routes of sheltered and undulating country could not survive the conditions which the shallow bury supported with difficulty on the flatter front in Flanders. Gradually a spirit of co-operation began to pervade all ranks of the Signal Service. The blue and white armband became a badge of comradeship. Everyone was out to help defeat the conditions which bade fair to strangle an over-burdened service. The result was manifested in many ways. Control of the wires in the forward area, with the greater responsibility and authority conferred thereby, improved the position of the Divisional signal officer, while at the same time it prepared him for a logical extension of the same principle which should in time make him subordinate to his immediate superior at the Corps. In the same way, the appointment of senior officers as O. i/c Signals at Army headquarters gave birth to a new power of co-ordination throughout the whole of each Army. It did not need much farther thought along the same lines to complete the chain of command in Signals by the creation of two posts which practically made the senior signal officer at Corps and Army a Signal Adviser to the Staff of his formation. Early in 1916, the O.C. Signals, Army, was released from his executive duties and appointed Deputy Director of Signals to the Army Commander with the rank of Colonel and with general supervision over the whole of the signal communications of the Army. A little later, a similar administrative reform took place at the Corps and for the first time the chain of command in the Signal Service was complete. These reforms were the direct outcome of the gradual but definite extension of Signal responsibilities, of which the first fruits had been the acceptance of responsibility for signals in the higher artillery formations and the general control of forward lines. They immensely strengthened the position of the Signal Service. Elaborate signal communications had become essential to the success of modern warfare. It had long been recognized in theory that the signal officer must be consulted beforehand, if operations were to be carried through according to programme. This principle, too often ignored by Staff officers, had now become an uncontrovertible fact. It was no longer to be a question of saying: "such and such are my dispositions; such and such signal communication must be forthcoming." Future operations must be modified by considerations of intercommunication problems in the same way that signal systems are dependent upon operations. The need for some such reform had already been well shown in the battles of 1915, particularly in the case of lower formations. Divisions and Brigades had commenced to split up into front and rear headquarters. In one particular case, a Divisional headquarters split up into three portions, while at the same time the Divisional artillery also divided into two, and each Brigade established an advanced and rear office. The result might have been foreseen. The Signal Company, already strained to its utmost capacity to deal with a normal number of signal offices, was quite unable to lay and maintain all the circuits required. At one time all the linemen were out on the lines at once. The artillery had to be left to run their own intercommunication as regards operators, and little could be done for them as regards lines. The visual signallers of the company were all employed on the telephone system and additional cyclist orderlies had to be borrowed. A gallant attempt was made to maintain touch, but it not unnaturally failed.

At one time this splitting up of headquarters and the still more aggravating constant moves of headquarters, because the Staff did not like their billets or because of enemy attention, became the rule rather than the exception. Gradually, however, the representations of signal officers, reinforced as they were by frequent failures of intercommunication that could be traced directly to the changes, began to have effect. The division into advanced and rear headquarters became a normal procedure, but it was recognized that the main responsibilities of the Signal Company consisted in maintaining communication between the fighting headquarters. Rear headquarters were connected, it is true, but they became of secondary importance during operations.

Another question intimately connected with the movements of formation headquarters was that of reliefs. The lower the formation and, therefore, the nearer the fighting line, the more frequently the troops became worn out and had to be relieved. This meant, of course, that the responsibility for signal communication in the same sector was constantly changing. Here, also, as time passed and experience was gained, improvements in organization took place. In the first few months of trench warfare, signal units moved out with their formations, carrying off with them every inch of cable or wire and every instrument and terminal. The incoming unit had to reconstruct the whole system of communications, often at the expense of several casualties, always with unnecessary expenditure of labour and stores. The disadvantages of this system were soon seen and individual officers handing over to men they could trust, left their lines in position, taking over in exchange an equivalent amount of wire or cable. Gradually, as such reliefs became a part of the normal routine of every unit, this practice became universal and the exaction of the quid pro quo in the form of line stores fell into disuse.

The same could not be said about instruments, however, and in the earlier days when the personnel of units was trained to work with improvised and unstandardized instruments, this dislike of exchanging to instruments probably of a quite different type was understandable. The disadvantages of the relief procedure in existence were certainly obvious, though acquiesced in by everyone concerned. In Brigades, particularly, and in Divisions to a great extent, moves were frequent, and the instrument repairers spent a considerable portion of their time in the signal office either installing, improving, or taking down the instruments on completion of a relief which had just taken place, or in preparation for a relief to come. Work thus proceeded under disadvantages, yet the custom persisted. Even in 1918, it was the exception rather than the rule for a Division to hand over its instruments in position to the incoming Division, though this was often done with test-panels, and, less commonly, with telephone exchanges. Perhaps the motive at the root of this policy of constant change was a low opinion of human nature; perhaps an affection for instruments that had been in use for many months. Whatever was the cause, it was one which might well receive the attention of future signal officers. If a complete system of office relief can be evolved and insisted upon, much will be achieved in the direction of greater efficiency and incidentally a policy of faith in one's fellow men will be inculcated with good effects.

One difficulty which was first experienced in this year to a serious extent was the lack of continuity of signal responsibility in areas. Every few days in the case of Brigades, every few weeks in the case of Divisions, every two or three months in the case of Corps, a move took place and the whole of the signal system of the areas concerned was either replaced altogether or changed hands. There was no continuity of policy or of acquaintance with the system or the area. Even the habit of handing over line systems complete had its draw-backs from this point of view. Records were seldom exhaustive in detail or up to date. The new company or section had to grope their way through the system of their predecessors step by step; a proceeding nearly as difficult in some cases as re-laying the whole. Some co-ordinating authority was required, who would have a general and continuous responsibility over the area, who could insist on a standard system of records, and who could provide a nucleus of personnel who would remain in the area independent of reliefs. These directions of reform were indicated from the first and formed a prominent subject of discussion in the many Army and Corps signal conferences that were held during the year.

Out of these conferences arose a policy which differed in different Armies and Corps, but followed the same general lines. In one Army a cable detachment was attached from the Corps to each Division in the Corps. The personnel of this detachment was given general charge of the working of all forward lines, manning of test-points, keeping of records, etc. This personnel belonged still to the Corps Signal Company and did not move with Division. In Second Army area, on the other hand, properly constituted area parties consisting of one officer and eight men were formed — also from the personnel of the cable sections — and one such party was told off to each area to control the maintenance of all lines not in use. The original proposal, which contained the germ of the whole future official policy of the Signal Service, was as follows: —

"Before laying cable or wire the new officer taking over should refer to the officer in charge of the permanent party. Once taken over maintenance to be by unit. Officers to keep a complete record of all wires in their area. These permanent parties to be attached to each Infantry Brigade Section."

In putting forward this proposal, it is interesting to note that an analogy was drawn from the German system already in use, where one officer and forty men looked after, and were responsible for, area signals.

To carry any regional policy into effect, a careful delimitation of areas was necessary and, in November, 1915, the Director of Signals ruled that signal areas should be allotted by Armies to Corps, by Corps to Divisions and by Divisions to Brigades. About the same time, the O.C. Corps Signals was made generally responsible for the signal communication in the Corps area generally, and in order to ensure continuity of policy it was decided that the Corps Signal Company should not move with the Corps, but should remain in the area when the new Corps headquarters took over.[6] This, of course, separated the Corps Signal Company in many cases from its Corps and led to some confusion and difficulty of identification. This position of affairs was permitted to persist for some time, but was finally set right by the allotment of letters to the Corps Signal Company, the original First Corps Signal Company becoming "A" Corps Signal Company, and so on throughout the alphabet as far as necessary.

At the same time as the reforms referred to above, it was represented to the Staff that signal efficiency could not be reckoned upon unless the frequent changes of headquarters so common in 1915 were reduced to a minimum. This was a fact that was rapidly becoming self-evident. Changes of headquarters, other than those taking place at reliefs, were invariably followed by a certain dislocation of traffic which was quite clearly unavoidable with the present complicated line system. Still more so did this become the case when buried cable became general. Buried routes could not be moved and the rebuilding of a buried system took many nights of the labour of large parties of men. New spurs, even, could not be dug in a few hours. Either the Staff must learn to stay in one place between reliefs or they must be satisfied with indifferent signal communication for some days after each move. The problem was solved partly by the appreciation by the Staff of the quite unnecessary difficulties they were putting in the way of their own signal companies, partly by the improvement in the methods of fortification of headquarters that was rapidly taking place.

Some of the past moves of headquarters had been capricious. Far more had been made to avoid enemy shelling or to find better protection. As headquarters were more thoroughly protected against direct hits, and as the Staff came to realize the difficulties under which the Signal Service was working, moves of headquarters were reduced to a minimum. Moves between reliefs became less common except in the event of advance or retreat. A greater victory still was gained for signals when it became an established custom for incoming headquarters almost invariably to take over the headquarters of the formation or unit they were relieving. This, again, was in the main due to the necessity for fortification on an ever increasing scale. Suitable headquarters were very few. Those that existed were constantly being improved both from the point of view of convenience and of safety. Soon there was no temptation for an incoming Staff to go elsewhere than where their predecessors had lived. Thus 1915 and the early months of 1916 saw the crystallization of the comparatively rigid signal system necessary to cope with the conditions of stationary- warfare. The main features of the new system were: —

(1) The general introduction of the telephone.
(2) The protection of forward lines.
(3) The devising of supplementary means of bridging the zone between the front line and the limit of hostile shelling.
(4) The extension of Signal Service responsibility forward to the front line, and to artillery and infantry communications.
(5) The allotment of areas of signal responsibility and the consequent attainment of a continuity of policy in such areas.
(6) The evolution of a good system of signal relief generally.
(7) The recognition of the necessity for a Chain of Command within the Signal Service.
(8) The commencement of the recognition by the Staff of the importance of the Signal Service. While still quite properly regarded as the servant of the Staff, the signal officer was in process of being raised to the status of a Confidential Adviser.

On these lines advancement continued throughout 1916. The latter year was one of great re-organizations. Before, however, it is possible to proceed to deal with the principal features of this — perhaps the most interesting year of trench warfare as regards signals — it is necessary to consider in some detail the weakness which caused the death of the forward telephone system, or rather its paralysis and atrophy.


  1. It is a fact that constant unchanging conditions — whether wet or dry — exert a much less injurious influence upon the insulation of a cable than constant alternation from one to the other. The test referred to above was therefore perhaps of most value as providing a useful example of a law, well-known, but likely to be overlooked.
  2. In late September, 1916, a method was tried of combining buried cable with a communication trench. A trench eight feet deep was dug, cable laid therein and then two feet filled in. There were possibilities in the idea but it proved a failure, (a) the task was too great for a single night and the depth was not obtained; (b) the bottom of the trench became too muddy and was impassable in places; (c) the organization and execution of the work was defective.
  3. Kilowatt
  4. Wireless interference.
  5. This figure was a normal range in the most suitable country. On the Somme it was often necessary to push Wilson sets forward to limit the range to 6,000 yards.
  6. This particular reform was not popular either with Corps Staffs or A.D. Signals. It was given a fair trial in the late winter of 1916, but was soon dropped.

«-- The Signal Service in the European War of 1914 to 1918
Chapter V
Chapter IV Chapter VI