Jason Clarke Antiques has dated this piece to the 1870s.
This magnificent and extremely weighty forty eight inch flat section example with bevelled edges is divided into inches on one side with numbering which graduates in thirds of an inch (1 to 144 rising in threes).

It is superbly engraved to the centre to, Baker, 244 High Holborn, London.
According to some of the company’s advertising, the Baker firm had roots stretching back to 1765 but Charles Baker (1820-1894) is actively recognised to have been trading by 1851 and presented itself as both opticians and instrument makers.

Baker is more commonly associated with the making of microscopes to most modern collectors but voluminous catalogues held at The Borthwick Institute in York suggest that he was as prolific as the likes of WF Stanley and Elliotts in the range of instruments available.

The company continued after Baker’s death under the stewardship of the Curteis family until it was finally subsumed by Vickers Instruments Ltd in 1959 although a repair business called “Rekab” continued to be managed by Michael Curteis until his death in 1965.
Circa 1870
Jason Clarke Antiques has dated this piece to the 1870s.
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