Cooke, Troughton & Simms

Cooke, Troughton & Simms was a British instrument-making firm formed in York in 1922 by the merger of T. Cooke & Sons and Troughton & Simms

in 1924 the company became a wholly owned subsidiary of Vickers. A new factory was built in 1938 in Haxby Road, York and the firm's telescope-making business was acquired by Sir Howard Grubb, Parsons and Co. Ltd. During the Second World War 3,300 people were employed by the company. In 1963 it became a part of the new Vickers Instruments Ltd and they ceased trading in 1988.

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:

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