Winston Churchill: The World Crisis:
Colonel Boraston’s account is studiously vague as to the objectives sought for by his chief on July 1. The plan of the British and French was admittedly to pierce the whole German trench system on a front of many kilometres, and then by wheeling outwards—the British to the north-east and north and the French to the south-east—to roll up from the flanks the exposed portions of the German line; and British and French cavalry divisions were held ready to be pushed forward through the gap so made. The French objective was to gain the rising ground east of the Somme south of Péronne, while ‘the corresponding British objective’ was ‘the semicircle of high ground running from the neighbourhood of Le Transloy through Bapaume to Achiet-le-Grand.’ But these objectives, says Colonel Boraston, were not expected to be reached in the first assault:
These Somme positions were objectives for the armies concerned rather than for the troops from time to time engaged in the attack. They marked the stage at which it was thought that the penetration would be deep enough… to enable the Allied armies to turn their attention to the second stage of the battle, that is to say, the rolling up of the German forces on the flank of the point of rupture.
It was certainly contemplated from the beginning that the battle would be long and hard fought; but it will be seen that the time factor is thus left altogether indefinite. One remains under the impression that it was comparatively immaterial whether this penetrating advance and outward movement were to be effected in a few days, a week, a fortnight, or even longer. But this argument cannot be sustained. The whole effectiveness of the plan depended on the speed of its execution. If for instance an interval of two or three days intervened between the penetration and the outward wheel, the enemy’s line would be switched back on both sides of the gap and a whole new web of fortifications would obstruct a further advance. All prospect of a great rupture followed by rolling up the flanks was dependent upon a rate of progress so rapid as to preclude the construction and organization by the enemy of fresh defensive lines. If the Joffre-Haig plan was to achieve any success apart from mere attrition, progress must be continuous and rapid, and the objectives specified must be attained at the latest in two or three days.
If this were not secured, the great attack would have failed. Other attacks might subsequently be planned and might be locally successful, but the scheme of a grand rupture was definitely at an end. It is easy to prove that rapid progress was in fact contemplated and resolutely bid for. The use by Haig of his artillery clearly indicates the immediate ambitions which were in view. Instead of concentrating the fire on the first lines which were to be assaulted, the British artillery was dispersed in its action over the second and remoter lines and on many strong points far in the rear, the hope clearly being that all these would be reached in the course of the first day’s or two-days’ fighting. The position of the British and French cavalry in close proximity to the battle front also reveals indisputably the hopes and expectations of the commanders...