At the same time a jumping barrage of smoke shells and H.E. was to cover the advance of the Tanks and infantry.
The secrecy of the attack made it impossible for any registering shots to be fired, and the ranges could be worked out in theory only.
Several squadrons of the R.A.F. were to co-operate, flying low; their especial work being to bomb enemy Headquarters.
The cavalry were also billed to co-operate.
Special wire-pulling Tanks fitted with grapnels were employed to clear convenient broad lanes through the wire for them, and their needs were throughout carefully considered.
For one reason and another, however, the cavalry did not, after all, find it possible to take much part in the fighting.
The preparations for the battle were of the thorough and laborious kind always requisite for a “full-dress” attack.
An immense amount of railway movement was necessary in order to bring up the three Tank Brigades, whose component parts were a good deal scattered. Thirty-six trainloads of twelve Tanks each had to be dealt with, and their stores besides.
For the sake of secrecy all this movement was done after dark. There were only two minor accidents, otherwise the whole scheme was worked out exactly to programme.
The usual huge dumps of petrol and grease and special stores had to be formed. Most of them were made in neighbouring woods, where the Tanks also lay up. Havrincourt Wood and Desert Wood were, for instance, used for main dumps, and as lying-up places for the 1st and 2nd Brigades, for in these woods the hornbeam undergrowth had not yet shed its leaves and the Tanks and their stores could lie in perfect secrecy.