1933 only 30% of the factory was in use. In 1938, the telescope manufacturing part of the business was sold to Grubb Parsons. Wartime Production In 1936 a list of military requirements was issued by the minister for co-ordination of defence, Sir Thomas Inskip. One result was the building of a new factory in 1938 in Haxby Road, York. The firm's telescope-making business was acquired by Sir Howard Grubb, Parsons and Co. Ltd. At the outbreak of war in 1939 the UK government placed large orders for military sighting telescopes and theodolites. By 1940 output was only limited by the supply of raw materials and orders exceeded £1,000,000. During the Second World War many Tavistock theodolites were used in artillery observation and many other applications by survey regiments. During this period 3,300 people were employed by the company. Anticipating post war trading conditions several new products such as medical microscopes suited to a civilian role were developed using tooling created for wartime production. At the end of the Second World War, a film entitled Cooke Troughton & Simms in Wartime 1939-1945 was released which documented the manufacturing processes used to produce many of the optical instruments which were used in tanks, aeroplanes and on ships. The Haxby Road factory was re-designated "Kingsway North" with a workforce of 900 in 1939, rising to 2000 in 1941 and peaking in 1943. Post War Products In 1963 CTS became a part of the new Vickers Instruments Ltd. During this period it made the Vickers V.11 and V.22 theodolites. The company produced a range of precision microscopes and survey equipment including theodolites and it manufactured one of the first usable interference microscopes. A 1950 catalogue listed the following range of microscopes: M1005/M1025 - student microscopes M1000 - 'general purpose' microscope M2000 - microscope for 'routine and research investigations' M3000 - The M2000 with vertical adjustment to the stage M4000 - 'universal stand' for visual and photographic examination M6000 - stereo microscope M7000 - polarizing microscope Cooke, Troughton & Simms ceased trading in 1988. Upon closure all buildings on the site were demolished, leaving only the concrete foundations and as of October 2018, the site is still waiting to be redeveloped. References Manufacturing companies of the United Kingdom