Cooke, Troughton & Simms

Thomas Cooke set up a business in York in 1837 making astronomical telescopes. One early notable instrument was a 4.5 inch equatorial refractor which would have been exceptional at the time. In 1851 Cooke built a 7.25 inch equatorial telescope. Cooke made the optical elements himself for both these instruments. Thomas Cooke built a reputation for high quality optics and, as well as smaller instruments, supplied large instruments to observatories around the world.

From the outset in 1826 and earlier Troughton and Simms of London excelled in the high precision work of dividing circles and so provided many observatories with large transit instruments and supplied national surveys such as the Ordnance Survey, with large transit theodolites.

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.

In 1922 with business in a depressed state Cooke and Troughton & Simms merged with head offices at York. However foreign competition was strong. In particular the Swiss firm of Wild was making theodolites which were lighter, smaller and more accurate than CTS products.