A Decimal Clock is a timepiece displaying time according to the decimal system, dividing the day into 10 hours, each hour into 100 minutes, and each minute into 100 seconds. Introduced during the French Revolution as part of the decimalisation of weights and measures, decimal clocks were produced only for a brief period and are now exceptionally rare. Surviving examples are highly prized for their historical significance and unusual method of timekeeping. *Related Terms*\ Clock, French Revolution, Horology, Regulator Clock, Timepiece.