Colin Brand Antiques has dated this piece to the 19th Century.

It became a limited company in 1915 and in 1922 it merged with T. Cooke & Sons to form Cooke, Troughton & Simms.
The firm produced hundreds of astronomical instruments such as mural circles, transit circles, sextants, and other astronomical instruments for observatories around the world.

Previously, Troughton had been a sole proprietor, and before that he was in partnership with his brother John. John died and Edward took on Simms in 1826. Edward Troughton died in 1835.
In 1876 they supplied the Imperial Standards Of Length gauges mounted at Trafalgar Square in London UK.
Colin Brand Antiques has dated this piece to the 19th Century.
Antiques with a story to tell and where history finds a home
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