English silver lever watch by Charles Frodsham Circa 1853

Silver lever pocket watch 
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An English silver open faced lever pocket watch, Hallmarked London circa 1853. Gilt full plate movement with English lever escapement, cut and compensated bimetallic balance, diamond end stone.
White enamel dial with black Roman numerals and black outer minute track, subsidiary seconds at 6 o’clock, blued steel spade hands.
Polished consular case, signed inner cap, case and cap numbered. Case, dial & movement signed, case also stamped J.T.W.
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Diameter: 54 mm
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Signed: Charles Frodsham AD Fmsz
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Since 1852, Frodsham’s best watches have been distinguished by the code AD Fmsz. By substituting numbers for the letters spelling Frodsham, the code translates to AD 1850, the year the firm introduced a new watch calibre and commenced making high quality watches. Their position among the first rank of English watchmakers has been recognized ever since.