A large number of articles and published material, as well as copies of notes and reports, relating to the development of Ricardo & Co Engineers (1927) Ltd and its engineering projects, mainly to do with internal combustion engines with reference to tanks, many written by its founder Sir Harry R Ricardo, covering the period 1912 - 1967. Together with a microfilm copy of the articles.
Military conflict took place during every year of the 20th Century. There were only short periods of time that the world was free of war. The total number of deaths caused by war during the 20th Century has been estimated at 187 million and is probably higher.