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. For the 3rd Brigade, however, there was no wood conveniently near, and the Tanks lay out in a village with camouflage clothes thrown over them, painted to represent bricks and tiles. For the forward dumps splendid work was done by the 3rd Army’s light railways, who handled astonishing masses of stores; for example, 165,000 gallons of petrol, 541,000 rounds of 6-pounder ammunition, and 5,000,000 rounds of S.A.A. Beyond the light railways the Tank fills were transported by supply Tanks. All these preparations had to be carried out as secretly as possible. Moves were made after dark. No new wheel tracks must be made. There must be no reference to the battle over the telephone. There must be no extra horse or mechanical transport seen about in daylight. The concentration of Tanks in the background was explained by the establishment of an alleged new training area. Tank Corps Headquarters established with the army at Albert was disguised under the plausible alias of “The Tank Corps Training Office.” There must be no increase in aeroplane activity for reconnaissance purposes. The same troops were to continue to hold the line, the attacking forces passing through them, and those in the line were as far as possible to be kept in the dark as to the new operations. There was always a danger of men in the trenches being taken prisoner in some raid, and the less they knew the better. Oosthoek Wood had not been forgotten.