Marriott whom he had met while in South Africa. Marriott occasionally sent Swinton news of technical developments that might have a military application, and his letter described a machine he had seen in Antwerp, an American-made Holt Caterpillar Tractor. He suggested that the machine might be useful for transport, and Swinton passed the information on to several military and political figures who he thought might be interested. At the time, with no apparent prospect of war, the idea seemed to be a matter only of transport efficiency, and Swinton forgot about the matter. The idea of a caterpillar track as the basis for a fighting vehicle occurred to him only as he drove from St. Omer to Calais on the morning of 19 October. In Britain, David Roberts of Richard Hornsby & Sons had attempted starting in 1911 to interest British military officials in a tracked vehicle, but failed. Benjamin Holt of the Holt Manufacturing Company bought the patents related to the "chain track" track-type tractor from Richard Hornsby & Sons in 1914 for £4,000. When World War I broke out, with the problem of trench warfare and the difficulty of transporting supplies to the front, the pulling power of crawling-type tractors drew the attention of the military. The British War Office conducted trials with Holt tractors at Aldershot but saw them only as suitable for towing heavy artillery. Major Swinton was sent to France as an army war correspondent. In November 1914 he suggested to Sir Maurice Hankey, Secretary of the Committee of Imperial Defence, the construction of a bullet-proof, tracked vehicle that could destroy enemy machine guns. In July 1915, Swinton was given a prominent post in the War Office and became aware of the Landship Committee, which was entirely under the control of Admiralty; he formed a working friendship with its secretary, Albert Gerald Stern. Swinton was able to persuade the prime minister to call an inter-departmental conference on 28 August 1915, which ensured the army's cooperation with the Landship Committee's work and it was Swinton who drew up the specifications of the performance which the army would require. In 1916 Swinton was promoted to Lieutenant Colonel and given responsibility for training the first tank units. He created the first tactical instructions for armoured warfare. The Royal Commission on Awards to Inventors decided after the war that the inventors of the tank were Sir William Tritton, managing