First decimal watch

Nearly two years before decimal time became law, on January 27, 1792, Louis Berthoud was commissioned by the Chevalier de Borda to manufacture this decimal watch chronometer, which was completed on June 19, 1793. It displays the Roman numerals I…X in an inner circle and 100 marks with every 5, numbered from 5…100, around the outer edge. 

[Source]