The Home Depot at Wool had also increased, and there had been changes and developments at the Ministry of Munitions and in the Tank production side generally. It is in fact impossible in a single chapter to give more than a brief indication of this universal and increasing “back area” activity. To begin with the changes in the home organisation and in the production of Tanks. The “New” Tank Committee was, as we have already related, a success. In December 1917 and January 1918 it saw a rather interesting new phase, when Majors Drain and Alden, of the U.S. Tank Corps, attended certain of its meetings, and when the manufacture for the British and American Armies of the Mark VIII. or “Allied Tank” was decided upon. This Tank was never fought, but its projection is perhaps interesting as an example of inter-Allied solidarity. By January 1918 proposals for an expansion from nine to eighteen Battalions and for a reorganisation of Tank control had been put forward. These proposals were eventually (in April 1918) discussed by the Inter-Allied Tank Committee, a sort of sub-committee of the Versailles Conference, on which the British, French and American Tank Corps were represented. But neither men nor really constructive thought could then be spared from the immediate needs of meeting the German onrush, and nothing was done to realise their proposals until that onrush was finally stemmed. But in July 1918 the business was taken up again. It was decided to expand the Tank Corps to thirty-four Battalions armed with about six thousand machines. II In December 1917 the manufacturing situation was not particularly satisfactory. As late as August 20 the Commander-in-Chief had, it will be remembered, laid down, in an official letter, an order of priority in which there were four categories preferred to Tanks. “The manufacture of Tanks should not be allowed to interfere in any way with: “(1) The output of aeroplanes. “(2) The output of guns and ammunition. “(3) The provision of mechanical transport, spare parts therefor, and petrol tractors up to the scale demanded. “(4) The provision of locomotives up to the scale demanded. And though by December the views of the authorities had changed considerably, the sudden expansion of the Tank building programme was not easy. In October 1917, 700 Mark IV. Tanks had already been delivered in France, and a balance of about 500 was still due. But the Fighting Side was anxious that these should not all be of the unimproved Mark IV. pattern. For up to now no change in the design had been made since the first Mark IV. had been delivered. It was decided, therefore, that some of the 500 should be given Ricardo engines and Epicyclic gears, and that others should be fitted as Supply Tanks.