(S.R.R.), of i officer, in other ranks, was allotted to every 10 groupes. There was for the whole unit a Section de pare, or repair park, similar to that of the Mechanical Transport Service. This was found necessary so soon as tanks had been delivered in any number, owing to the amount of tuning-up, minor repair work and even alterations which had to be done.
Numerous faults at once developed in these entirely new machines (as had been the experience of the British), but thanks to the time available before they went into action, certain defects were discovered and remedied. The first was that some parts of the machines wore out very quickly, necessitating the maintenance of a very large stock of spares. The thickness of steel plate where vertical was not proof against the German " K " bullet, and it was found necessary to add an outer plate of 5-5 mm. to the vertical armour of the Schneider ma- chines, and 8-5 mm. to that of the St. Chamond machines. On the whole the defects discovered in the Schneider tanks were not such as to give reason to suppose that they would not be able to go into action in the spring ; but those of the St. Chamond were more serious. The design was found clumsy and the machine liable to ditch. In addition to breakdowns in the power system and failure in details, there was a lack of rigidity in the whole machine, and the tracks of the first machines were too narrow.
Delivery of both types was extremely slow, especially of the St. Chamond machines. At the end of March, though personnel for 1 5 of the latter was ready, there was not one machine service- able. At this time, on the eve of the great 1017 offensive of which so much was expected, the Artillerie d'Assaut, instead of being in possession of the 800 tanks which were to have been ready by the previous autumn, had received not more than 208 Schneider and 48 St. Chamond machines. There were for this operation, therefore, only 8 fully and 2 partly trained groupes of Schneider and i of St. Chamond tanks, and not 40 groupes as originally contemplated; and of the 160 Schneider machines only one had been fitted with the extra bullet-proof protection. In view of the diminution of the tank force from what was ex- pected to be available, and with the example of the result of the action of the British in the previous Sept. before it, the French High Command had grave doubts whether to make use of tanks in the coming operations or to wait until there should be suffi- cient to exercise a greater influence. It was finally decided to throw all possible weight into the attack.
April 16 was the baptism of fire of the French tanks, in Gen. Nivelle's unsuccessful attempt to break through the German line along the Chemin des Dames, E. of Craonne.
Eight Schneider groupes cooperated with the French V. Army. They were divided into two parts of three and five groupes respec- tively. One party did not succeed in crossing the German line, though a few machines reached it, and it suffered severely from the enemy's guns posted on the Craonne Plateau. The other party suc- ceeded in crossing the enemy's second line, but were not followed up by the infantry, owing to the German machine-gun fire. Two Schneider groupes and one St. Chamond groupe allotted to the French IV. Army for employment on the iyth were not thrown into the fight, as the German artillery observation posts were not first cap- tured by the infantry a lesson of the action of the l6th. The offen- sive failed ; and though the new arm showed the utmost devotion and gallantry, and its intervention saved many lives, it did not achieve the success that was hoped. But the conditions were almost as unfavourable for the employment of tanks as they could be, and the tactics employed were not those urged by those responsible for the new arm. The attack was not a surprise, being preceded by a heavy bombardment, which, however, did not succeed in overcoming the German artillery, and was made in broad daylight, without any smoke-screen, against a position which permitted of direct observed artillery fire against the tanks both when approaching and when they reached the enemy's positions. The plan, also, in which certain infantry units had been trained to cooperate, was that the tanks were to attack the German third defensive line after the infantry should have gained the first and second, and were not to advance until after this had been achieved. The Germans, who were prepared for the attack, therefore, had even additional time before the tanks ap- peared, and the result was that their guns caught many of the ma- chines in column before they deployed.
The machines themselves showed certain faults they were de- ficient in speed and climbing capacity, the latter defect being accentuated by the fact that since the Somme the Germans had increased the width of their trenches. They also proved, as was
known before would be the case, vulnerable to direct hits of H.E.
shell, by which many machines were set on fire. Amongst other points of design in which modification was found necessary was that of isolating the petrol tanks from the interior of the machine, im- proving the means of communication, the power of observation, the
ventilation, and various details of mechanism, and of widening the tracks. On the whole the Schneider machines stood the trial best.
In the next tank attack, carried out on May 5 by the VI. Army, the battle of Laffaux Mill, the three groupes employed advanced with the infantry with marked success, especially in the case of the Schneider machines. The counter-battery work of the French was good and the enemy observation posts were destroyed or masked; and the tanks did not remain too long in advanced positions where the infantry were checked.
For nearly six months the tanks did not again go into action. During this period great efforts were made to remedy the de- fects disclosed, to expedite the delivery of machines, which was much in arrears, and of spare parts, the demand for which (as in England) had been found very greatly to exceed any anticipa- tions, and to augment the establishment of repair units. In preparation for the next operation great care was taken in the training of infantry with the tanks in attack and in tank tactics generally. On Oct. 23 five groupes of tanks took part in the battle of La Malmaison along the Chemin des Dames. Their assistance was most valuable.
Owing to previous heavy rain, and the bombardment which had continued for six days and six nights, the ground was extremely difficult, and in the centre the tanks were not of so much help in the first phase of the attack as later. This state of the ground and the lack of surprise again discounted to a great extent the preparatory training undergone by the units of the Artillerie^ d'Assaut. The practice which had been carried out beforehand with the attacking infantry, however, proved of great value, as did the work of the special unditching sections. The ground had been carefully recon- noitred and aerial photographs supplied. The Germans relied on this occasion more on their advanced field guns for defence, and had also organized numerous special machine-gun posts furnished with plen- tiful supplies of armour-piercing ammunition. But owing to the counter-battery work of the French the tanks were not so much damaged by the German guns as in April, in spite of the fact that the attack was not a surprise. Two days later some St. Chamond machines again operated with success.
Apart from the projected light tanks, the necessity for an improved medium tank had been realized before April 1917, and the subject was under consideration throughout the year. The main directions in which the April offensive showed improvement to be necessary were the desirability of mounting the gun in a turret to give all-round fire, of mounting a 75-mm. field gun in place. of the shortened 75, and of increasing the size of the tracks and the power of the engine. Designs for a new medium machine (C.A.3) were prepared in Aug. 1917, but were aban- doned after the battle of La Malmaison because the further im- provement then found desirable, i.e. the provision of 6 to 7 H.P. per ton weight, a trench-crossing capacity of 3 metres, and an ability to climb ahead or astern, showed that the designs were already out of date, and would be more so by the time the machines could be made. At the end of Oct. it was decided to suspend the construction of an improved type of medium tanks and to concentrate on that of the light machines; and in Dec. the idea was finally dropped. The question of providing heavy tanks was taken up at the end of 1916 as a result of the opera- tions of the British machines in Sept., and in order to have available a machine which would be complementary to the light tanks it was hoped would be made. A project was put forward for a heavy tank weighing 38 tons to carry a ios-mm. gun, but its execution was postponed in view of the demands that might be made for other machines. Two experimental heavy tanks, one with mechanical and the other with electrical transmission, were tried, and it was decided to investigate in the direction of still heavier machines.
In regard to the type which will always be especially associated with the French, the Char leger, or Renault tank, first suggested by Gen. Estienne in July, and for which designs were prepared in Nov. 1916, the commander-in-chief in that month expressed his desire for 1,000 of such machines. But whereas those respon- sible for supply had, in the case of the medium tank, pressed forward the construction of one type, the St. Chamond, without military approval of the design, in the case of the Renault 'every obstacle seems to have been placed in the way of manufacture of this machine, for which army H.Q. and the Arlillerie d'Assaut
