The decision to forego all bombardment previous to attack was justified by the following considerations :
In conformity with the general plan of action, the concealment of all Artillery preparations became of paramount importance. This involved minute attention being paid to all measures tending to ensure accuracy of fire on the day of attack without previous registration.
The front held by the Fourth Army was approximately 27,000 yds.
The attack was to be delivered on a front of 19,000 yards, expanding gradually to one of 30,000 yards on the final objective.
The depth of intended advance attained in some places 12,000 yards, exclusive of further ground earmarked for the exploitation of success.
The attack was to be delivered by three Corps. On the right, the Canadian Corps was to attack on a three Divisional front of 7,000 yards between the AMIENS - ROYE road and AMIENS - NESLE railway. The action of the First French Army on the right permitted the Artillery of the Canadian Corps to confine its attention solely to its immediate front, but the operations on the right of the Corps were of a somewhat intricate nature necessitating very careful timing of Artillery barrages and bombardments.
In the centre, the Austr. Corps was to attack on a two Divisional front of 7,000 yards between the AMIENS - NESLE railway and the R. SOMME. Its Artillery was afforded a simple plan of action.
On the left, the III Corps was to attack with three Divisions on a front of some 5,000 yards, from the R. SOMME to the north. The Corps was required to establish a strong flank, on the high ground north of the R. SOMME, covering the operations of the Fourth Army generally. Much difficult ground, intersected by woods and ravines, had to be overcome.
The depth of the flank to be formed necessitated the employment of heavy guns to form a protective barrage, and special attention being paid to hostile artillery to the N.E. and outside the zone of attack.
The Artillery of the Fourth Army was reinforced by :
& also by the Horse Artillery of the Cavalry Corps, raising the available Artillery resources to :
The total number of guns and howitzers available was approximately 2000, of which 672 were heavy guns or howitzers. The strength in detail was as follows:
18 Brigades of Field Artillery and 9 Brigades of Heavy Artillery were allotted to both Canadian and Austr. Corps, and 16 Brigades of Field Artillery and 8 Brigades of Heavy Artillery were allotted to III Corps.
The Artillery tasks comprised :
Normal activity was ordered to be maintained on the front up to Zero. Two factors only were authorised to permit a departure from this procedure. Firstly, the improbable eventuality of a hostile attack in force. Secondly, the possibility of the enemy discovering our intentions and developing a heavy bombardment, more especially with gas shells, on our troops while moving into position on Zero night. In this latter eventuality, orders were issued that all guns available for counter-battery work, without any reservation, on the front concerned, should engage the hostile Artillery and crush it by weight of metal.
The measures taken to ensure secrecy and surprise may be summarised as follows:
In order to carry out the operations, it was necessary for the Fourth Army to take over some 7000 yards of front from the French, immediately prior to the operations. This necessity added considerably to the difficulties of the Artillery preliminary arrangements to be overcome.
The reinforcing Artillery was concentrated in the area between 31st July and 6th August. It was necessary to site the guns well forward in order to cover the Infantry advance as long as possible, and to bring effective fire to bear on hostile Artillery positions and communications. In some cases this led to minor complications as regards trajectory of shells.
The Artillery already in position was moved forward gradually, some guns being left temporarily in the old positions to maintain the normal Artillery activity of the front.
All new positions were re-sected, bearings taken, and battery boards prepared for the Heavy Artillery by the Topo. Sections.
The incoming batteries occupied positions and dumped ammunition gradually on the five nights previous to Zero. With minor exceptions, due to the late arrival of units, the occupation of positions was completed on the night preceding Zero night.
No work on positions likely to be visible by aerial observation was permitted. Guns were camouflaged and remained silent. Wagon line positions were selected with a view to concealment. The endeavours to conceal all movement by day might have been negatived by the necessity for combining this satisfactorily with the watering of a very large number of horses. Fortunately the weather favoured concealment of movement. Under similar circumstances in future operations, it will be necessary to make elaborate preparations for the watering of horses under cover.
The dumping of ammunition was rendered a severe task by the late arrival of some units, and by the fact that in many cases lorries did not arrive with their units. It was successfully performed, but where it is necessary to prepare for a battle of this magnitude with secrecy and despatch, a large number of extra lorries should be placed at Army disposal to facilitate ammunition arrangements.
The Army Calibration Range proved of great service, a very large number of guns being calibrated behind the line immediately before the operations.
Minute arrangements were made with the object of obtaining accuracy of fire. Those took the form of ensuring the checking of all laying and lines of fire, the testing of sights, etc., immediately before or during the operations.
Stress was laid on the importance of the timely issue of orders, and on the danger of introducing changes into the same subsequent to issue.
Army Artillery orders affecting the operations generally were issued through the General Staff, those of a purely technical nature direct to the Artillery.
The demands for Camouflage material were large, and a big stock should be kept in hand to meet sudden requirements.
Army "Maps" rendered valuable assistance in the production of "Barrage" Maps.
Generally speaking, the preliminary arrangements worked smoothly and well, largely due to the zeal displayed by all ranks and the mutual assistance afforded by units.
For a brief spell, on the III Corps front, the arrangements appeared likely to be jeopardized by a German attack on "X" night, which resulted in the capture of a portion of our front system, but the difficulties created were successfully overcome.
Simplicity of barrage was obtained admirably on the Austr. and part of the Canadian Corps fronts. On both flanks local conditions connected with objectives or irregularity of our front line complicated matters somewhat and necessitated special Corps arrangements.
On the III Corps front, it was necessary to employ 60-pdrs to form a flank protective barrage.
The number of 18-pdrs available afforded a barrage of 1 gun to 25 yards approximately.
The general arrangements for barrage fire were as follows:
The 18-pdr barrage fire came down 200 yards in front of the Infantry taped line at Zero. All lifts were of 100 yards. The first lift was timed for Zero plus 3, the second for Zero plus 5, and the next 8 lifts at 3 minutes interval. Subsequent lifts were at 4 minutes interval. The barrage was timed to reach the first objective in about 2 hours, and a protective barrage was maintained until Zero plus 4 hours, when all barrage fire ceased.
The 4.5" barrage moved in advance of that of the 18-pounders.
In view of the nature of the ground, which was hard and comparatively free from craters, and of the weak nature of the hostile defences, it was left to Corps to employ either 18-pdr. shrapnel or H.E. with delay action fire for barrage purposes. Canadian and III Corps employed shrapnel; the Austr. Corps shrapnel and H.E.
Use was made of smoke shells locally, both for barrage purposes and to form smoke screens.
The barrages were remarkable for their accuracy.
The deciding factors in the nature of barrage to employ, as also in its rate of advance, are those of nature and state of ground and defences to be overcome.
Shrapnel may be regarded as efficacious under all circumstances of ground, and its advantages are pronounced on heavy shell-pitted ground. It is unmatched as a man-killer against troops in the open, but has not the same demoralizing effect as H.E. The difficulties connected with adjustment of height of burst lead to a somewhat large percentage of rounds being burst on the ground, where they are generally ineffective, or too high in air; moreover, the error introduced by the time of burning of the fuze, more especially at long ranges, makes a time shrapnel barrage compare unfavourably in accuracy and simplicity with that of H.E.
H.E. with non-delay fuze is very suitable on hard ground, provided the slope of ground is not unfavourable. It is very effective against entrenched troops. Infantry can advance very close under it without undue risk of casualties. It is not effective and should not be employed on soft or shell-pitted ground nor at long ranges.
H.E. with instantaneous fuze was not employed on this occasion, but affords an effective substitute for H.E. with delay action fuze on soft or shell-pitted ground, and is the only shell which can be relied on as effective at long ranges.
In employing H.E. generally, it must be remembered that the zone of dispersion is outwards and somewhat forward; there is but little back-blast.
10% of smoke shells forms a suitable proportion for barrage purposes.
In view of the nature of the enemy's defensive system, the fire of most of the Heavy Artillery, other than that employed for Counter-Battery work, was directed on strong points and localities, being timed to lift according to the advance of the Infantry. Roads and communications in the forward area were dealt with chiefly by 60-pdr fire.
For the later stages of the operations, lines of demarcation for Heavy Artillery fire, based on the probable progress of the Infantry, were laid down.
As the hostile Artillery was regarded as the chief menace to the attack, two-thirds of the available Heavy Artillery was allotted to deal with it. At Zero, the whole of this Counter-Battery Artillery opened fire on a pre-arranged programme. H.E. and 106 fuze were employed almost exclusively, except on the III Corps front where gas shells were used in addition against the batteries lying outside the intended zone of advance.
The German Artillery fire was rendered almost negligible.
Careful arrangements had been made for the continuance of vigorous Counter-Battery work in the latter stages of the offensive, but as the enemy's gun positions were practically all over-run, there was comparatively little scope for it, except on the III Corps front.
Before the attack, the enemy's Artillery strength was computed at about 680 guns. As a proportion of these lay outside the zone of operations, north of the SOMME, and the captures amount to some 450, but few can have succeeded in retiring.
An examination of the gun positions was of great interest. The positions generally were well concealed, and natural cover was made good use of, but very little artificial protection against shell fire was afforded. The ammunition was generally scattered in small dumps at and in the neighbourhood of the guns. It was placed in gun pits behind banks, in trenches, or in shell craters, according to local conditions, and camouflaged over.
As a rule, bomb-proof cover was not provided for the detachments at the gun positions.
Some guns had been hit and some dumps of ammunition blown up, but generally the damage caused to equipment and ammunition was comparatively small, in spite of the evident accuracy of the fire.
In the majority of cases, the detachments had evidently either been driven from their guns or had failed to man them. Some guns were captured with camouflage material over them and muzzle and breech covers still on. Where attempts had been made to keep the guns in action or to limber up, the havoc wrought amongst personnel and horses was generally great, and afforded excellent testimony to the accuracy of the fire and the destructive effect of the shells.
The destructive effect of Artillery fire, unless the enemy is manning his guns or replenishing ammunition, is always likely to be small.
We require, firstly, to concentrate all the means at our disposal towards the accurate location of the enemy Artillery positions, and secondly, to register carefully the positions so determined. It then remains to direct sudden and overwhelming concentrations of fire on the positions thus located and registered. This is the form recommended for pre-arranged destructive shoots.
In addition to this, our Counter-Batteries should be capable of concentrating their fire rapidly on hostile Artillery in response to the indications of aeroplane, balloon or ground observers. This is the form that impromptu destructive shoots should take.
The interior mechanism of this system, and the times and places for its application form a vast field of enterprise for all concerned, more especially for Counter Battery Staff Officers. The system is equally applicable to dealing with campsvillagesand centres of activity.
A map was issued by the Army indicating the special localities, bridges, railheads, etc., which were to be kept under fire by the 6-inch guns under the direction of the Corps.
Minute arrangements were made for pushing forward Artillery as soon as possible after Zero. Roads and tracks were allotted, and preparations made for bridging trenches rapidly. A few units were held mobile from the start, but the majority detailed to advance joined in the barrage and subsequently limbered up to advance at pre-determined times.
The Artillery may be said to have advanced in waves. First of all, Brigades under orders of Divisions, with Sections pushed out to the front. Then a limited number of 60-pdrs, and in the case of the Canadian Corps some 6" howitzers, since this Corps possessed fortunately two 6" howr. horse-drawn batteries. These were followed by further Brigades of Field Artillery. The remainder of the Field and Heavy Artillery moved up subsequently under Corps orders. The change in command from Corps to Divisions, and subsequently the resumption of command by Corps, worked smoothly. A special point was made of pushing forward the 6" guns as early as possible in order to shell the approaches and bridges over the SOMME.
The whole advance of the Artillery may be described as very successful. At the same time instances were not wanting to indicate the necessity of combined training in open warfare.
Experience points to the increased importance to be attached to pushing forward Sections in the immediate support of Battalions and Tanks. Unless they are pushed well forward, they are not likely to be available when required.
It is sufficient to attach one battery of 60-pdrs and one battery of 6-inch howitzers under a Brigade Commander R.G.A. to a Division. These should be placed under the orders of the C.R.A. of the Division. A larger force of Heavy Artillery becomes somewhat unwieldy for the Division to handle in moving warfare.
Many units carried portable bridges, and a few made use of them. They are not considered essential, but if not carried, ample provision should be made to carry tools. Material assistance was rendered to the Heavy Artillery of one Corps by the attachment to it of R.E. personnel and this procedure is recommended strongly.
Each Cavalry Brigade was accompanied in its advance by its own battery. R.H.A. Brigade Commanders remained with the Cavalry Divisional Commanders, acting as Artillery advisers. Every gun went forward with three ammunition wagons, i.e., 252 rounds in all. The moral effect produced by a few rounds fired against machine guns and local counter-attacks is reported as remarkable. The importance of pushing the R.H.A. guns well to the front, and handling them with great boldness, was demonstrated. Guns which were kept back proved of but little value, as the opportunity for their successful use quickly passed away.
Experience tends to show that Artillery support is as important to the Tank as it is to the Infantry. If Infantry move forward without the protection of barrage fire, they become a prey to machine guns. If Tanks excursionize out without Artillery support, they are liable to fall victims to a single gun. So long as they remain under the protection of the barrage, but little ill befalls them. In moving warfare it is just as essential to push forward sections of Artillery in the close support of Tanks as it is of Infantry Battalions.
On the fighting front only one Corps (Canadian) made an extended use of 6" Trench Mortars. These were employed as follows:
One Mortar accompanying the Infantry was knocked out by a direct hit early in the day. The remaining 11 succeeded in keeping in close touch with the Infantry. They engaged numerous machine gun nests, etc., which were holding up the advance and in this way were of the greatest assistance.
In every case in which a strong point was engaged by a Mortar, the enemy cleared off after a few rounds had been fired.
The two Mortars with the "Independent Force" also did useful work. They fired 50 rounds, and on occasion claim to have silenced an enemy Field battery.
At Zero hour the Anti-Aircraft guns were disposed:
1 section of each battery 1000 yards to 2000 yards behind the START line.
1 section of each battery in the "Balloon" zone.
The remaining sections covering rear areas.
The orders for the advance were:
Front section of each battery to advance as close as possible behind the Infantry.
Sections in "Balloon" area to advance with the balloons.
Rear sections to await further orders.
The above orders were carried out according to plan, and by the afternoon of 8th August, two sections of each battery were in action in the captured area, except on the northern flank where the depth of the advance was not great enough.
During 8th August, enemy aircraft showed little activity, and were dominated by our aeroplanes. 176 E.A. [enemy aircraft] were seen, of which 90 were engaged, although only 16 are reported to have crossed our lines.
On August 9th and 10th, enemy activity increased, the number of machines seen being 263 on 9th and 305 on 10th.
Between August 8th and August 14th, both dates inclusive, 7 enemy aeroplanes were crashed by A.A. fire and one damaged.
After August 8th, hostile bombing activity became marked in the forward areasmore especially at night. This was to a large extent negatived by pushing forward searchlights. In future operations, arrangements should be made to push these forward on the first day of operations.
The Corps Topographical Sections, assisted by topographical personnel from the Field Survey Battalion, resected all battery positions not already occupied, worked out centre lines to correspond with the tasks allotted to the various batteries, and in many cases provided map boards. The thoroughness with which this work was carried out assisted materially in enabling accurate barrage and counter-battery fire to be opened without previous registrations.
The Observation Groups moved forward on the day of battle, and from then on kept pace with the advance of the Heavy Artillery. It was found that the church towers and other buildings in the villages in the captured territory provided excellent flash spotting O.Ps. and these were made full use of.
The Sound Ranging Sections advanced on August 8th, and by the 10th had established bases covering the old AMIENS defence line. On August 12th it was decided to advance the Sound Ranging Sections further, and by the 15th they had their bases established to cover the new front.
The accuracy with which the work of Field Survey units was carried out prior to the operations and the promptness with which the Sound Rangers and Flash Spotters were established on the new line proved of the greatest assistance to the Artillery in carrying out their tasks.
The morning of 8th August was misty, and visibility remained indifferent until late in the day.
Very few 'NF' calls were sent, as the German batteries were soon overrun, but many 'GF' calls were sent and received.
In the Canadian Corps a special contact aeroplane was sent out to keep Divisions informed of the situation of their Field batteries. Batteries were provided with special panels to show:
There had not been time to equip all batteries with the special panels.
Some messages were dropped at the wrong stations by mistake.
Although the system was not perfected, it enabled Divisions to receive useful information earlier than they would have done otherwise. The system is one which merits attention with a view to future operations.
The system on which the advance of balloons was directed was:
On III Corps front, balloons worked 1000-2000 yards in advance of normal positions.
On Canadian and Australian Corps fronts all balloons were inflated before Zero, but were not then moved to forward positions owing to the prospect of visibility being much obscured and to the danger of their being knocked out by chance shots before they could do useful work.
Balloons were indicated the places which they were expected to reach at stated times. These advances, amounting in some cases to 10,000 yards, were successfully carried out, and by 3.0 p.m. on August 8th, the front was under observation by balloons at normal distances from the line.
The depth of the advance on August 8th made the upkeep of communication by telephone a matter of great difficulty, and reliance was placed chiefly on visual signalling and C.W. Wireless Sets.
The country lent itself well to visual signalling, and this form of communication was extensively and successfully used, lamps being the principal means employed.
C.W. Wireless Sets were used with success on Canadian and Australian Corps fronts; the amount of information received through this means was limited by:
One point brought out in these operations is that although the higher formation is responsible for upkeep of communication to the next lower formation, the latter must keep the former informed of intended moves, and must continue to send information back to their old Report Centre for transmission until the higher formation has established communication to the new Headquarters of the lower formation.
Failure to take these precautions led to one Brigade of Artillery being out of touch with its Divisional R.A. for the greater part of the day.
The following arrangements were made for passing Artillery information back:
Each Corps R.A. had direct lines to Divisional Artilleries and Corps H.A.
A Liaison Officer was established at each Corps R.A., H.Q., to transmit information direct to Army R.A. These Officers were given authority to send "Priority" telephone messages.
By these means information was quickly transmitted to Army H.Q.
Provision for the use of captured guns was made in preliminary orders and instructions. Parties were detailed to proceed to hostile battery positions as soon as these were captured; these parties were taken in some instances from batteries not under orders for an early advance while in other cases they were found from Trench Mortar personnel. All available information as regards types of guns and howitzers, range tables etc., was circulated beforehand.
Many of the captured guns were found to be deficient of sights or other essentials, but sufficient pieces were found complete to enable a considerable number to be used against the enemy.
In several instances valuable assistance was afforded the Infantry by turning the fire of captured guns on to localities which were temporarily holding them up. Unless the personnel to man the guns accompanies the Infantry the fire of the guns is likely to be masked.
As in the case of Mobile Trench Mortars, it was found that a few rounds were sufficient to break down the enemy's resistance and to enable the Infantry to push on.
During the course of these operations, many valuable documents were captured in the form of up-to-date Range Tables, handbooks, etc; it is suggested that the information so obtained should be widely circulated in pamphlet form. It is also suggested that instruction in German Artillery equipment should in future form part of the course at Artillery Schools.
One of the advantages of an attack carried out without previous bombardment is the high percentage of guns which are available for the day of battle. On August 8th, 98.5% of the Artillery strength was so available.
Practically no extra workshops were required beyond those accompanying normally the Canadian Corps.
The advance of Workshops commenced on the day of battle. Those that first went forward acted more as Store Shops than Workshops.
The advance of Workshops should be conducted in "leap-frog" fashion, those furthest to the rear being held mobile to move forward as soon as success is assured.
It is essential to have a "pool" system of lorries in Corps, permittingunder Corps ordersof supply lorries being used in an emergency for ammunition purposes and vice versa. This in no way prohibits Siege Park lorries being under the orders of the C.H.A., but merely legislates for the lorries under his command being available for general purposes if not required for those of the Artillery.
It is necessary to call attention to the importance of the lorries of the Artillery detailed for a concentration for battle, firstly, being fit for work, and secondly, arriving with their units. In both these respects arrangements were not altogether satisfactory.
For an advance it is essential to exercise the closest supervision over ammunition supply, more especially as regards the clearance of ammunition from vacated positions, if prohibitive waste is to be avoided. The arrangements of the Australian Corps worked excellently and some useful remarks on this subject by the G.O.C., R.A. of that Corps are added as an Appendix to this paper. [not reproduced]
The dumps of ammunition authorised by the Army were as follows:
18-pdr: 600 rounds per gun.
In addition echelons were kept full.
The number of rounds dumped erred somewhat on the large side, even allowing for the necessity which always exists to legislate for possible eventualities.
If special ammunition is required in large quantitiessuch, for example, as H.E. with delay action fuze for barrage purposesample warning must be given, as it is otherwise not practicable to adjust ammunition supply satisfactorily.
The total expenditure of ammunition on the Army front was:
August 8th: 448,953 rounds.
The expenditure in detail on August 8th was:
The average number of rounds per gun fired on August 8th was:
The economy in ammunition expenditure realised by the absence of preliminary bombardment is enormous.