ridge to Douai and beyond. Moreover, although it was evident that the enemy might, by a timely withdrawal, avoid a battle in the awkward salient still held by him between the Scarpe and the Ancre, no such withdrawal from his important Vimy Ridge positions was likely. He would be almost certain to fight for FIELD MARSHAL SIR DOUGLAS HAIG this ridge, and, as my object was to deal him a blow which would force him to use up reserves, it was important that he should not evade my attack. (3) With the forces at my disposal, even combined with what the French proposed to undertake in co-operation, I did not consider that any great strategical results were likely to be gained by following up a success on the front about Arras and to the south of it, beyond the capture of the objectives aimed at as described above. It was therefore my Intention to transfer my main offensive to another part of my front after these objectives had been secured. The front selected for these further operations was in Flanders. They were to be commenced as soon as possible after the Arras offensive, and continued throughout the Summer, so far as the forces at my disposal would permit. (4) The positions held by us in the Ypres salient since May, 1915, were far from satisfactory. They were completely overlooked by the enemy. Their defense involved a considerable strain on the troops occupying them, and they were certain to be costly to maintain against a serious attack, in which the enemy would enjoy all the advantages in observation and in the placing of his artillery. Our positions would be much improved by the capture of the MessinesWytschaete Ridge and of the high ground which extends thence northeastward for some seven miles and then trends north through Broodseinde and Passchendaele. The operation in its first stages was a very difficult one, and in 1916 I had judged that the general situation was not yet ripe to attempt it. In the Summer of 1917, however, as larger forces would be at my disposal, and as, in the Somme battle, our new armies had proved their ability to overcome the enemy's strongest defenses, and had lowered his power of resistance, I considered myself justified in undertaking it. Various preliminary steps had already been taken, including the necessary development of railways in the area, which had been proceeding quietly from early in 1916. I therefore hoped, after completing my Spring offensive further south, to be able to develop this Flanders attack without great delay, and to strike hard in the north before the enemy realized that the attack in the south would not be pressed further. (5) Subsequently, unexpected developments in the early weeks of the year necessitated certain modifications in my plans above described. New proposals for action were made by our French allies which entailed a considerable extension of my defensive front, a modification of the rôle previously allotted to the British armies, and an acceleration of the date of my opening attack. As a result of these proposals, I received instructions from his Majesty's Government to readjust my previous plans to meet the wishes of our allies. Accordingly, it was arranged that I should commence the offensive early in April on as great a scale as the extension of my front would permit, with due regard to defensive requirements on the rest of my line. The British attack, under the revised scheme, was, in the first instance, to be preparatory to a more decisive operation to be undertaken a little later by the French armies, in the subsequent stages of which the British forces were to co-operate to the fullest extent possible. It was further agreed that if this combined offensive did not produce the full results hoped for within a reasonable time, the main efforts of the British armies should then be transferred to Flanders, as I had originally intended. In this case our allies were to assist me by taking over as much as possible of the front held by my troops, and by carrying out, in combination with my Flanders attacks, such offensives on the French front as they might be able to undertake. (6) My original plan for the preliminary operations on the Arras front fortunately fitted in well with what was required of me under the revised scheme, and the necessary preparations were already in progress. In order to give full effect, however, to the new rôle allotted to me in this revised scheme, preparations for the attack in Flanders had to be restricted for the time being to what could be done by such troops and other labor as could not in any case be made available on the Arras front. Moreover, the carrying out of any offensive this year on the Flanders front became contingent on the degree of success attained by the new plan. (7) The chief events to note during the period of preparations for the Spring offensive were the retirement of the enemy on the Arras-Soissons front and the revolution in Russia. As regards the former, the redistribution of my forces necessitated by the enemy's withdrawal was easily made. The front decided on for my main attack on the Arras front lay almost altogether outside the area from which the enemy had retired, and my plans and preparations on that side were not deranged thereby. His retirement, however, did enable the enemy to avoid the danger of some of his troops being cut off by the converging attacks arranged for, and to that extent reduced the results which might have been attained by my operation as originally planned. The rôle of the 5th Army, too, had to be modified. Instead of attacking from the line of the Ancre simultaneously with the advance of the 3d Army from the northwest, it had now to follow up the retiring enemy and establish itself afresh in front of the Hindenburg line to which the enemy withdrew. This line had been very strongly fortified and sited with great care and skill to deny all advantages of position to any force attempting to attack it. The adjustments necessary, however, to enable me to carry out the more subsidiary rôle which had been alloted to my armies since the formation of my original plans, were comparatively simple, and caused no delay in my preparation for the Spring offensive. My task was, in the first instance, to attract as large hostile forces as possible to my front before the French offensive was launched, and my forces were still well placed for this purpose. The capture of such important tactical features as the Vimy Ridge and Monchy-le-Preux by the 1st and 3d Armies, combined with pressure by the 5th Army from the south against the front of the Hindenburg line, could be relied on to use up many of the enemy's divisions and to compel him to reinforce largely on the threatened front. The Russian revolution was of far more consequence in the approaching struggle. Even though the Russian armies might still prove capable of co-operating in the later phases of the 1917 campaign, the revolution at once destroyed any prospect that may previously have existed of these armies being able to combine with the Spring offensive in the west by the earlier date which had been fixed for it in the new plans made since the conference of November, 1916. Moreover, as the Italian offensive also could not be ready until some time after the date fixed by the new arrangement with the French for our combined operation, the situation became very different from that contemplated at the conference. It was decided, however, to proceed with the Spring offensive in the west, notwithstanding these serious drawbacks. Even though the prospects of any farreaching success were reduced, it would at least tend to relieve Russia of pres sure on her front while she was trying to reorganize her Government; and if she should fail to reorganize it, the Allies in the west had little, if anything, to gain by delaying their blow. Preparations were pushed on accordingly, the most urgent initial step being the development of adequate transport facilities. Spring Campaign-Preparations for Arras Offensive (8) When transport requirements on the front in question were first brought under consideration, the neighborhood was served by two single lines of railway, the combined capacity of which was less than half our estimated requirements. Considerable constructional work, therefore, both of standard and narrow gauge railway, had to be undertaken to meet our program. Roads also had to be im proved and adapted to the circumstances for which they were required, and preparations made to carry them forward rapidly as our troops advanced. For this latter purpose considerable use was made both in this and in the later offensives of plank roads. These were built chiefly of heavy beech slabs laid side by side, and were found of great utility, being capable of rapid construction over almost any nature of ground. By these means the accumulation of the vast stocks of munitions and stores of all kinds required for our offensive, and their distribution to the troops, were made possible. The numberless other preparatory measures taken for the Somme offensive were again repeated, with such improvements and additions as previous experience dictated. Hutting and other accommodation for the troops concentrated in the area had to be provided in great quantity. An adequate water supply had to be guaranteed, necessitating the erection of numerous pumping installations, the laying of many miles of pipe lines, and the construction of reservoirs. Very extensive mining and tunneling operations were carried out. In particular, advantage was taken of the existence of a large system of underground quarries and cellars in Arras and its suburbs to provide safe quarters for a great number of troops. Electric light was installed in these caves and cellars, which were linked together by tunnels, and the whole connected by long subways with our trench system east of the town. A problem peculiar to the launching of a great offensive from a town arose from the difficulty of insuring the punctual debouching of troops and the avoidance of confusion and congestion in the streets both before the assault and during the progress of the battle. This problem was met by the most careful and complete organization of routes, reflect ing the highest credit on the staffs concerned. The Enemy's Defenses 9. Prior to our offensive, the new German lines of defense on the British front ran in a general northwesterly direction from St. Quentin to the village of Tilloy-lez-Mofflaines, immediately southeast of Arras. Thence the German original trench systems continued northward across the valley of the Scarpe River to the dominating Vimy Ridge, which, rising to a height of some 475 feet, commands a wide view to the southeast, east, and north. Thereafter the opposing lines left the high ground, and, skirting the western suburbs of Lens, stretched northward to the Channel across a flat country of rivers, dikes, and canals, the dead level of which is broken by the line of hills stretching from Wytschaete northeastward to Passchendaele and Staden. The front attacked by the 3d and 1st Armies on the morning of April 9 extended from just north of the village of Croisilles, southeast of Arras, to just south of Givenchy-en-Gohelle at the northern foot of Vimy Ridge, a distance of nearly fifteen miles. It included between four and five miles of the northern end of the Hindenburg line, which had been built to meet the experience of the Somme battle. Further north, the original German defenses in this sector were arranged on the same principle as those which we had already captured further south. They comprised three separate trench systems, connected by a powerful switch line running from the Scarpe at Fampoux to Lievin, and formed a highly organized defensive belt some two to five miles in depth. In addition, from three to six miles further east a new line of resistance was just approaching completion. This system, known as the Drocourt-Queant line, formed a northern extension of the Hindenburg line, with which it is linked up at Queant. Fight for Aerial Supremacy (10) The great strength of these defenses demanded very thorough artillery preparation, and this in turn could only be carried out effectively with the aid of our air service. Our activity in the air, therefore, increased with the growing severity of our bombardment. A period of very heavy air fighting ensued, culminating in the days immediately preceding the attack in a struggle of the utmost intensity for local supremacy in the air. Losses on both sides were severe, but the offensive tactics most gallantly persisted in by our fighting airplanes secured our artillery machines from serious interference and enabled our guns to carry out their work effectively. At the same time bombing machines caused great damage and loss to the enemy by a constant succession of successful raids directed against his dumps, railways, airdromes, and bullets. The Bombardment (11) Three weeks prior to the attack the systematic cutting of the enemy's wire was commenced, while our heavy artillery searched the enemy's back areas and communications. Night firing, wire cutting, and bombardment of hostile trenches, strong points, and billets continued steadily and with increasing intensity on the whole battle front, till the days immediately preceding the attack, when the general bombardment was opened. gas During the latter period extensive discharges were carried out, and many successful raids were undertaken by day and night along the whole front to be attacked. Organized bombardments took place also on other parts of our front, particularly in the Ypres sector. The Troops Employed (12) The main attack was intrusted to the 3d and 1st Armies under the command of General Sir E. H. H. Allenby, G. C. M. G., K. C. B., and General Sir H. S. Horne, K. C. B., respectively. The Method of Attack (13) The attack on the front of the 3d and 1st Armies was planned to be carried out by a succession of comparatively short advances, the separate stages of which were arranged to correspond approximately with the enemy's successive systems of defense. As each stage was reached a short pause was to take place, to enable the troops detailed for the attack on the next objective to form up for the assault. Tanks, which on many occasions since their first use in September of last year had done excellent service, were attached to each corps for the assault and again did admirable work in co-operation with our infantry. Their assistance was particularly valuable in the capture of hostile strong points, such as Telegraph Hill and the Harp, two powerful redoubts situated to the south of Tilloy-lezMofflaines and Railway Triangle, a stronghold formed by the junction of the Lens and Douai lines, east of Arras. The Arras Battle (14) The general attack on April 9 was launched at 5:30 A. M. under cover of a most effective artillery barrage. Closely following the tornado of our shell fire our gallant infantry poured like a flood across the German lines, overwhelming the enemy's garri sons. Within forty minutes of the opening of the battle practically the whole of the German front-line system on the front attacked had been stormed and taken. Only on the extreme left fierce fighting was still taking place for the possession of the enemy's trenches on the slopes of Hill 145 at the northern end of the Vimy Ridge. At 7:30 A. M. the advance was resumed objectives. Somewhat against the second was greater opposition was now encountered, and at the hour at which these objectives were timed to have been captured strong parties of the enemy were still holding out on the high ground north of Tilloy-lez-Mofflaines, known as Observation Ridge, and in Railway Triangle. Four army corps were placed at the disposal of General Allenby, with an additional Army Corps Headquarters to be used as occasion might demand. Cavalry also brought up into the 3d Army area, in case the development of the battle should give rise to an opportunity for the employment of mounted troops on a considerable scale. The attack of the 1st Army on the Vimy Ridge was carried out by the Canadian corps. It was further arranged that, as soon as the Vimy Ridge had been secured, the troops in line on the front of the Canadian corps should extend the area of attack northward as far as the left bank of the Souchez River. additional army corps was also at the disposal of the 1st Army in reserve. An The greater part of the divisions employed in the attack were composed of troops drawn from the English counties. These, with Scottish, Canadian, and South African troops, accomplished a most striking success. My plans provided for the co-operation of the 4th and 5th Armies under the command respectively of General Sir Henry S. Rawlinson, Bart., G. C. V. O., K. C. B., and General Sir H. de la P. Gough, K. C. B., K. C. V. O., as soon as the development of my main assault should permit of their effective action. North of the Scarpe, north country and Scottish territorial troops, attacking east of Roclincourt, were met by heavy machinegun fire. Their advance was delayed, but not checked. On the left the Canadians rapidly overran the German positions, and by 9:30 A. M., in spite of difficult going over wet and sticky ground, had carried the village of Les Tilleuls and La Folie Farm. By 12 noon men from the eastern counties of England had captured Observation Ridge and, with the exception of Railway Triangle, the whole of our second objectives were in our possession, from south of Neuville Vitasse, stormed by London territorials, to north of La Folie Farm. A large number of prisoners had already been taken, including practically a whole battalion of the 162d German Regiment at the Harp. Meanwhile our artillery had begun to move |