item has been sold.
mahogany & satinwood wheel barometer by Salmoni
impressive English wheel barometer is made of finely
figured mahogany with satinwood cross-banding inlay
and edged with boxwood stringing. The
silvered engraved barometer dial, with black enamel
filling, is 10 inches in diameter and graduated in
inches from 28 to 31.
just below the main dial is an alcohol-filled level
dial which is signed by the maker P. Salmoni, Bath,
and above the main is a thermometer with convex glass
and over that a removable dry/damp indicator topped
off by the swan neck pediment and brass finial.
44 inches high
Peter Selmoni (Salmoni) is recorded as having been
working at 4, Milsom St, Bath between 1829 and 1841
moving to 24, Union St, Bath in 1833 until 1841.
operation of the 'wheel' or 'banjo' barometer was
invented by Robert Hooke in 1664, but not commercialized
until over a century later. It is comprised of a Torricellian
tube bent like a 'U' with two weights attached by
a line, run over a pulley, which is connected to the
hand on the dial. The one weight rides on the mercury
column and the other acts as a counter weight to keep
tension in the line. As the mercury moves up or down
the line rotates the pulley which moves the hand on
Banjo or wheel barometers started being manufactured
in the late 18th century in France and expanded to
England in the early 19th century when a number of
Italian immigrants started producing the cases. The
earlier models tend to feature mahogany with marquetry
in contrasting woods and inlay lines on the edges