Fine Geo III mahogany stick barometer, signed on the silvered dial Troughton London, with vernier index and a mercury thermometer. Scale graduated in Fahrenheit degrees, provided with a second scale of temperature corrections in hundredths of an English inch, calculated for a pressure of 30 inches of mercury.
Mahogany case with scroll pediment having carved wood terminals and brass finial, ivory float to the cistern for adjusting the level of mercury.
Length 38 inches. (96.52 cm)
Date c. 1780.
Edward Troughton established himself as the leading maker of instruments in England after the death of Jesse Ramsden in 1800. Troughton won the Copley Medal in 1809 for his methods of dividing instruments, a development traced from Henry Hindley and Jesse Ramsden.