Rare Swiss silver lever inking cylinder chronograph Circa 1879

Silver open faced inking chronograph by Patek Philippe
–
A fine and rare Swiss silver open faced keyless lever inking cylinder chronograph, circa 1879. 3/4 Plate gilt finished keyless cylinder movement, 8 jewels, plain three armed brass balance. White enamel dial calibrated for 60 seconds, Arabic numerals, large central hand with ink bowl and discharging pointer, subsidiary dial for 60 minute register. Case with snap on back, button in the crown to discharge ink, chronograph activated/stopped by depressing the left button and right button for reset. Case numbered, dial signed.
–
Diameter: 57 mm
–
Signed: Patek Philippe & Co Genève