Quiet Street Antiques of Bath has dated this piece to the 1800s.
, with the numeric scale on the left-hand side, and the mercury tube is original, with its 'ball' reservoir.

William & Samuel Jones worked as a highly regarded firm of barometer and scientific instrument makers in London from approximately 1790-1850. (See a full chapter on their work and history in "Barometers" by Goodison pages 168-169.
Quiet Street Antiques of Bath has dated this piece to the 1800s.
Fine antiques at sensible prices
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