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## Decimal Time - CalendarsThere have been many efforts to reform the Gregorian calendar. The Gregorian calendar itself was a 1582 reform of the Julian Calendar, which was in turn a reform of the Roman Replublican calendar by Julius Caesar in 45 BCE. Many other types of calendars have been used around the world and some are still in use. The primary obsticles to calendar reform are that religion and custom favor the existing calendar, and that incompatible cycles, such as days, weeks, months, seasons and years, are very difficult to rationalize with each other. Many calendar systems are based on the phases of the moon, which do not go evenly into a solar year, but the Julian, Gregorian and most of their derivative calendars are based on the seasons of the year, and have months of arbitrary lengths, usually 12. Since 365 days cannot be evenly divided by 12 or 10, the five odd days must be distributed in some way. Then there is slightly less than a quarter-day left over, which requires that additional days must be added every few years to keep the seasons from moving. It is not possible to reconcile more than one of these cycles with a completely decimal system, but there have been proposals for 10-day weeks or 10-month years. ## French Republican Calendar
The French Republican Calendar was used in France and countries controlled by France
from 1793 to 1805. This calendar was very similar to the ancient Egyptian and
Alexandrian calendars, which are still used in Ethiopia and by the Coptic
Church. Not only did the Republican Calendar include a decimal week, but
also decimal time. Months of the Republican
Calendar were divided into three ## DécadesThe ten days of each décade were called:
## MonthsThe months are shown below. Starting dates are approximate, and may fall one or two days later in some years.
## Complementary DaysThe five or six days (depending on leap years) added to the end of the year were calledSansculotides or jours complémentaires (complementary days). There were several different naming conventions, including the following:
## Leap YearsLeap years, calledsextile because they contained a sixth complementary
day, occurred whenever two consecutive autumnal
equinoxes happened to fall 366 days apart, as observed in Paris, which
happened in the years III, VII and XI. A period of four years, at the end of
which the addition of one day was necessary, was called a franciade,
However, had the calendar continued in use,
there would have been five years between the leap years XV and XX.
There was also a problem that when the equinox occurred close to midnight, the
margin for error made it impossible to predict whether it would fall on the
day before or after midnight.
In the year III Gilbert Romme proposed rules similar to those of the Gregorian calendar, so that years divisible by 4 would be leap years, unless they were divisible by 100 and not divisible by 400. Also, the year 4000 would not be a leap year. However, he was sentenced to the guillotine and committed suicide shortly after, and the original equinox rule was followed, instead, with the first leap day occurring three months after his death. This method has the benefit that Republican years start on the same day in the Gregorian calendar for long periods; for instance, all years start on September 22 between 1993 and 2092.
Some concordances printed in France after 1805 continued having every four years
after year 11 be leap years, i.e. 15, 19, 23, 27, 31, etc. Some in
France today also calculate leap years this way, applying Romme's reformed
rules to the year previous to what it would have been, so that the extra day
is inserted immediately There are some who use a rule that from the year 20 on, years divisible by 4 are leap years, unless they are also divisible by 128. There seems to be no historical precedent for this rule. ## Converting to Gregorian CalendarThe following table displays dates according to the Common Era for the first day of several years of the Republican Era, according to four methods of determining leap years:- Original rule: years start on equinox
- Romme's revised rule: leap day added at end of years divisible by four, except centuries
- Continuous rule: leap day inserted before years divisible by four, except centuries
- 128-year rule: leap day added at end of years divisible by four, unless divisible by 128
## The New Digital Standard Calendar (NDSC)According to The Digital Time web site: This calendar contains 10 months with 10 days each. Therefore, a year lasts 100 days. At present, the calendar is synchronized so that the 01/01/2000 (old time) precisely coincides with the 0/0/2000 NDSC. There is no more "week;" a week is replaced by a month.The New Digital Standard Time (NDST) is French decimal time, synchronized with UTC. NDSC months are numbered 0-9 and named Nuller, Prier, Secter, Trier, Quattrer, Penter, Sexter, Septer, Octer and Noner. The days of the month are likewise numbered 0-9, and are named Yourday, Myday, Momday, Dadday, Poorday, Giveday, Getday, Workday, Loveday, Restday. ## William Gatchel's Standard/Metric CalendarThis Standard/Metric Calendar is actually the Gregorian calendar with 10-day weeks, plus French decimal time. 10 days = 1 metric week ## Richard Ortiz's Metric CalendarAccording to Richard Ortiz's web page: In tune with revamping the entire chronological system, the New Year date/time is set to correspond to the Summer Solstice - Old June 21. This adds to the cosmological wholeness of the scheme in that the Metric New Year coincides with Natures New Year. ## Hal Mann's Decimal CalendarAccording to Hal Mann's web page: I propose that the calendar be divided into 10 months, instead of 12. Each month would be either 36 or 37 days long. Odd-numbered months would be 37 days long, and even-numbered months would be 36 days long. In leap years, the extra day would remain tacked on to the end of February (to keep from mucking up fixed-date holidays), becoming February 37th... In order to have only 10 months, I did away with June and July. ## Annus Novus Decimal CalendarThe Annus Novus Decimal Calendar System is the calendar of the Empire of Atlantium, which claims to be an independent "microstate" within the city of Sydney, Australia. The Annus Novus year is of the standard terrestrial duration. The Annus Novus Calendar divides the year into 10 months alternating between 36 and 37 days in length, and 73 weeks of 5 days. In leap years - which are concurrent with those of the Gregorian system, to aid simplicity - an intercalary 1-day month called the Intercalarius is inserted between the last day of the old year and the start of the new year.The months have names derived from Latin: Primus, Secundus, Tertius, Quartarius, Quintus, Sextarius, Septimus, Octavus, Nonus and Decimus. The odd-numbered months have 36 days and the even-numbered ones have 37. The weekday names are similar to the first five days French Republican Calendar's décade: Primidi, Secundi, Tertidi, Quartidi and
Quintidi. Years are numbered from the end of the Pleistocene Era, about 8520 BCE, so 2001 CE is 10520 "of the New Era".
The first day of the year (1 Primidi) is always on January 1 on the Gregorian calendar.
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