The present historians, on the contrary, feel tempted to adopt the simple method of their Hebrew predecessor, who, having picked out one plum, so often blandly continues: “And the rest of the acts of the Trench Warfare Department and all that they did, are they not written in the book of the archives of the War Office?” However, it is possible that the Hebrew historian honestly believed that the lost books of the Chronicles were really available to the inquiring reader. The present authors have no such illusion about War Office papers, and therefore propose to give at least an outline of the vicissitudes and fluctuations of early Tank control. The chief persons of the Drama remain throughout: _The War Office_: (1) In its capacity as Ordnance, and (2) in its capacity as General Staff. Later (3) as the Tank Department, War Office. _G.H.Q._: (1) In its main capacity, and as (2) The Experiments Committee. Later, the _H.B.M.G.C._ Finally, the Tank Corps. _The Admiralty_: (1) In its capacity as the Land Ship Committee, and (2) as Squadron 20 of the R.N.A.S. _The Ministry of Munitions_: (1) In its capacity as the Trench Warfare Department; (2) in its capacity as the Inventions Department. (3) Later, as the Mechanical Warfare Supply Department (really another Tank Committee). (4) Later still, as the Tank Supply Department. _The successive Main Tank Committees_: (1) The Joint Naval and Military Committee (which did not survive Act I.). (2) The Tank Supply Committee, afterwards called the Advisory Committee of the Tank Supply Department, and divided into a main committee and a sub-committee. (It was this sub-committee which afterwards formed the backbone of the very active and occasionally criticised M.W.S.D., before referred to). Later, (3) after a gap, the First Tank Committee; (4) the Second reconstructed Tank Committee. _Grand Chorus of Directors General, Interdepartmental Conferences, Manufacturers, and Workshop Personnel._ III We find that the period from August 1915 to February 1916 constitutes a kind of Act I. in the history of Tank administration and manufacture, for the 1914 and early 1915 period is too dim and legendary to serve as anything but prologue. During the whole of the Act I. period it was the Admiralty and the Joint Land Ship Committee which played the “leads.” It was the Admiralty which defrayed the whole cost of the extensive experimental work and provided the necessary personnel, and it was by members of the Joint Committee in consultation that the Mark I. Tank, “Mother,” was ultimately designed. On September 11, two months after Colonel Swinton’s visit, the Experiments Committee, G.H.Q., laid down in an excellent and far-sighted memorandum what were the qualities which they desired should be aimed at in designs for the caterpillar cruiser and what were the tactical purposes which it must serve.