The present watch is a rather unusual school masterpiece or watchmaking complication a watchmaker has to be able to construct in order to be recognised as a master watchmaker.
It indicates not only the standard time and seconds but also decimal time and seconds.
Decimal time is the representation of the time of the day using decimally related units. This term is often used to refer specifically to French Revolutionary Time, which divides the day into 10 decimal hours, each decimal hour into 100 decimal minutes and each decimal minute into 100 decimal seconds, as opposed to the common standard time, which divides the day into 24 hours, each hour into 60 minutes and each minute into 60 seconds.
Decimal time was introduced during the French Revolution in the decree of 5 October 1793. Although clocks and watches were produced indicating both standard time with numbers 1-24 and decimal time with numbers 1-10, decimal time never caught on. It was not officially used until the beginning of the Republican year III, 22 September 1794, and was officially suspended on 7 April 1795. The French Republican Calendar, which was introduced at the same time and divided the month into three décades of 10 days each, eventually also fell out of use, and was abolished at the end of 1805.
In 1897 another attempt at the decimalization of time was made when the Bureau des Longitudes created the Commission de décimalisation du temps with the mathematician Henri Poincaré as secretary. The commission proposed a compromise of retaining the 24-hour day, but dividing each hour into 100 decimal minutes, and each minute into 100 seconds. The plan did not gain acceptance and was abandoned in 1900.