Small English duplex in a silver open face case Circa 1883

A small English duplex in a silver open-faced case, hallmarked London circa 1883. Keywind gilt Lepine caliber movement with suspended going barrel, polished steel Geneva stopwork. Plain cock with diamond endstone, polished steel regulator, plain three-arm steel balance with blue steel spiral hairspring. Duplex escapement, brass escape wheel, ruby locking jewel. White enamel dial with subsidiary seconds, Roman numerals, blue steel hands. Silver open-faced case with decorative chased and engraved back, wound and set through the silver inner dome. Maker’s mark ‘WD’.