Although Marie Antoinette would find it difficult to deal with it, the French Revolution of 1789 had more in mind than simply overthrowing the monarchy. Revolutionaries sought to liberate the nation from its past, particularly from the clutches of the Catholic Church, and to lead France into a more glorious and prosperous future. They did this in part by radically changing their measurements of the passage of time.
Throughout the 18th century, most French people were Catholic, as it was the only religion allowed to be openly practiced in the country and had been since Catholicism was repealed Edict of Nantes in 1685. As such, the nation had traditionally adhered to the 12-month Gregorian calendar – itself based on even older, sexagesimal (6-unit) divisible systems adopted by the Babylonians and Egyptians – while the French clocks all 60 minutes and seconds ran.
But if there was little reason aside from tradition to continue using the established chronology system, the revolutionaries figured why not transform it into a more rational, scientifically sound method, just as the revolution itself sought to bring stability and new order to French society than whole? And what system could be better suited than that of the decimal, which already ruled the weights and measures of the nation. So the point was not to abolish the privileges of the First and Second Estates, but to abolish the power of the Church to levy taxes or just Drowning en masse by non-judging Catholic priests, France’s post-Revolution neophyte government, set about reforming the empire’s calendars and clocks.
The concept of decimal time, which breaks a day into multiples of 10, was first proposed more than thirty years ago when French mathematician Jean le Rond d’Alembert argued 1754: “It would be very desirable that all divisions, for example of the livre, the sou, the toise, the day, the hour, etc., were from tens to tens. This division would lead to much simpler and more convenient calculations, and would be much preferable to the arbitrary division of the livre into twenty sous, the sou into twelve deniers, the day into twenty-four hours, the hour into sixty minutes, etc.”
On the eve of the revolution the idea had evolved into a year divided into 12 months of 30 days each, whose names are inspired by harvests and the prevailing weather in Paris during their occurrence. That there are 365 days in the year is an unchanging fact dictated by the Earth’s motion around our local star. With 12 months of 30 days each, there were 5 days (6 in a leap year!) left. The revolutionaries reserved these for national holidays.
Each week was divided into 10 days, each day was divided into 10 equal hours, these were divided into 100 minutes, with each minute divided into 100 seconds (about 1.5 times longer than conventional minutes) and each second into 1000 “steps”. was divided. Individual levels could also be subdivided into 1000 even smaller units called “Quatierces”. The introduction of levels would also lead to the creation of a new unit of length called “half a hand’s breadth”. This is the distance that the twilight zone travels along the equator in the course of a plane, and is equal to one billionth of that of the planet’s circumference — about 4 centimeters.
Decimal time was officially adopted by Decree of the National Convention of 1793, “The day, from midnight to midnight, is divided into ten parts, each part into ten others, and so on down to the smallest measurable part of duration.” Thus, midnight would be denoted as 00:00, while noon would be 5:00.
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At midnight on the autumnal equinox on September 22 of that year, the Gregorian calendar of France ushered in the 1st Vendémiaire Year II of the French Republican calendar. From then on, each New Year would begin at midnight of the Autumnal Equinox, as observed by the Paris Observatory.
“The New Calendar Was Based on Two Principles”, a 2017 exhibition at the International Museum of Watches, Looking for noon at five o’clock, written down. “That the Republican year should coincide with the movement of the planets, and that it should measure time more accurately and symmetrically, employing the decimal system wherever possible. She was non-religious, advocating a rational approach and honoring the seasons and working in the fields.”
The main advantage of a decimal time system is that since the basis for dividing time is the same as that used to represent it, the entire time representation can be treated as a single string.
On the one hand, this system offered the clear advantage that both the number base for defining time and the number base for dividing are the same number. For example quick, how many seconds are there in three hours? The answer, most people will Google, is 10,800 – 60 seconds/minute x 60 minutes/hour x 3 hours. In decimal time you simply get 30,000 – 3 hours x 10,000 seconds/hour.
However, due to an oversight in its otherwise logical design due to gaps in astronomical knowledge, the Republican calendar had difficulty incorporating leap years properly. “The four-year period, after which a day must ordinarily be added, is called Franciade, in commemoration of the revolution which, after four years of effort, brought France to a republican government, decided by the National Convention. “The fourth year of the Franciade is called sextile.”
The problem is that when we count New Year’s leap years at midnight on the autumnal equinox in Paris, they don’t consistently occur every four years. After equinoxes, the first leap year of the Republican calendar would actually have to occur in year III, while the leaps in years XV and XX would occur half a decade apart.
There were also more practical issues with moving national chronology to an entirely new system, such as the fact that people already had flawless clocks that they would have to replace if decimal time stayed in effect. It was also extremely unpopular with the working class, who under the Republican calendar received only one day off in ten (plus half a day on the fifth), rather than the existing Gregorian day of seven, let alone the traditional ten-day week Sunday services devastated as Sunday would cease to exist.
Overall, the idea simply failed to gain public support – despite edicts calling for the creation of decimal-based clocks – and was officially shelved on April 7, 1795. The French then took a quick break with metric time, which similarly measured the passage of time in factors of ten but based on conventional seconds (aka 1/86400ths of a day). Of course, all these efforts were shattered when Napoleon proclaimed himself Emperor in 1804, made peace with the Vatican, and reinstated the Gregorian calendar, sending both the Republican calendar and decimal time into the dustbin of history. The lesson here is unless You put yourself in a time loop with TNG, don’t try to fix something that isn’t already broken, especially if it could get you a trip to the guillotine.
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