A polished black slate eight-day mantel clock with perpetual calendar and moonphase by Japy Freres, circa 1890.

The twin barrelled drum movement of typical Parisian form has a visible Brocot escapement with ruby pallets mounted within the two-pieced enamel Roman dial. Employing a countwheel system the clock strikes the hours and half-hours on a single bell. The striking train indexes the separate perpetual calendar movement once per day. The calendar is displayed on a five inch enamel dial with outer month chapter and day and date subsidiary dials and moonphase indication. The perpetual calendar is so-called as it automatically adjusts for the unequal length of months as well as adjusting for leap years.

The polished black slate case has a ribbed front and corresponding shaped moulded base.