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"ARNOLD & DENT, (/) 84 Strand, London, No. 1131"
box 6 inches sq.
During the perion 1830-1840 when John Roger Arnold and E. J. Dent were in business together, Arnold & Dent made some 600 chronometers. This one dates from around 1838, and was purchased by the U.S. Coast Survey. The U.S. Coast and Geodetic Survey transferred it to the Smithsonian in 1955. It is a 48-hour instrument, with an early Earnshaw spring detent escapement, and indications for hours, minutes, seconds, and up and down.
Ref: Vaudrey Mercer, John Arnold & Son, Chronometer Makers, 1762-1843 (London, 1972).
Arnold & Dent