An antique 18th century silver pocket watch. Turtle shell outer case, with 19th century paper 'W.J. Zanstra & Zoon Uurwerkmakers te Akkrum'. In first grade (925/1000) English silver inner case, marked with English lion passant, London city mark, year letter H, and master mark 'HE' or 'HF'. Silver dial with Arabic and Roman numeral indications, centrally featuring a depiction of a figure and shell and the name 'Drills' = John Drills, active in London in the mid-18th century.