[D66] [XIUHPOHUALLI] Feb 13 / Feb 23

Fri Mar 12 19:52:05 CET 2021

https://www.britannica.com/science/calendar/The-Gregorian-calendar

  The Julian calendar

In the mid-1st century bceJulius Caesar invited astronomer Sosigenes of 
Alexandria to advise him about the reform of the calendar, and Sosigenes 
decided that the only practical step was to abandon the lunar calendar 
altogether. Months must be arranged on a seasonal basis, and a tropical 
(solar) year used, as in the Egyptian calendar, but with its length 
taken as 365 1/4 days.

To remove the immense discrepancy between calendar date and equinox, it 
was decided that the year known in modern times as 46 bce should have 
two intercalations. The first was the customary intercalation of the 
Roman republican calendar due that year, *the insertion of 23 days 
following February 23*. The second intercalation, to bring the calendar 
in step with the equinoxes, was achieved by inserting two additional 
months between the end of November and the beginning of December. This 
insertion amounted to an addition of *67 days*, making a year of no less 
than _*445 days* and causing the beginning of *March 45 bce *in the 
Roman republican calendar to fall on what is still called January 1 of 
the Julian calendar._

Previous errors having been corrected, the next step was to prevent 
their recurrence. Here Sosigenes’ suggestion about a tropical year was 
adopted and any pretense to a lunar calendar was rejected. The figure of 
365.25 days was accepted for the tropical year, and, to achieve this by 
a simple civil reckoning, Caesar directed that a calendar year of 365 
days be adopted and that an extra day be intercalated every fourth year. 
Since February ordinarily had 28 days, February 24 was the sixth day 
(using inclusive numbering) before the Kalendae, or beginning of March, 
and was known as the sexto-kalendae; the intercalary day, when it 
appeared, was in effect a “doubling” of the sexto-kalendae and was 
called the bis-sexto-kalendae. This practice led to the term bissextile 
being used to refer to such a leap year. The name leap year is a later 
connotation, probably derived from the Old Norse hlaupa (“to leap”) and 
used because, in a bissextile year, any fixed festival after February 
leaps forward, falling on the second weekday from that on which it fell 
the previous year, not on the next weekday as it would do in an ordinary 
year.

Apparently, the Pontifices misinterpreted the edict and inserted the 
intercalation too frequently. The error arose because of the Roman 
practice of inclusive numbering, so that an intercalation once every 
fourth year meant to them intercalating every three years, because a 
bissextile year was counted as the first year of the subsequent 
four-year period. This error continued undetected for 36 years, during 
which period 12 days instead of nine were added. The emperor Augustus 
then made a correction by omitting intercalary days between 8 bce and 8 
ce. As a consequence, it was not until several decades after its 
inception that the Julian calendar came into proper operation, a fact 
that is important in chronology but is all too frequently forgotten.

It seems that the months of the Julian calendar were taken over from the 
Roman republican calendar but were slightly modified to provide a more 
even pattern of numbering. The republican calendar months of March, May, 
and Quintilis (July), which had each possessed 31 days, were retained 
unaltered. Although there is some doubt about the specific details, 
changes may have occurred in the following way. Except for October, all 
the months that had previously had only 29 days had either one or two 
days added. January, September, and November received two days, bringing 
their totals to 31, while April, June, Sextilis (August), and December 
received one day each, bringing their totals to 30. October was reduced 
by one day to a total of 30 days and February increased to 29 days, or 
30 in a bissextile year. With the exception of February, the scheme 
resulted in months having 30 or 31 days alternately throughout the year. 
And in order to help farmers, Caesar issued an almanac showing on which 
dates of his new calendar various seasonal astronomical phenomena would 
occur.

These arrangements for the months can only have remained in force for a 
short time, because in 8 bce changes were made by Augustus. In 44 bce, 
the second year of the Julian calendar, the Senate proposed that the 
name of the month Quintilis be changed to Julius (July), in honour of 
Julius Caesar, and in 8 bce the name of Sextilis was similarly changed 
to Augustus (August). Perhaps because Augustus felt that his month must 
have at least as many days as Julius Caesar’s, February was reduced to 
28 days and August increased to 31. But because this made three 31-day 
months (July, August, and September) appear in succession, Augustus is 
supposed to have reduced September to 30 days, added a day to October to 
make it 31 days, reduced November by one day to 30 days, and increased 
December from 30 to 31 days, giving the months the lengths they have today.

Several scholars, however, believe that Caesar originally left February 
with 28 days (in order to avoid affecting certain religious rites 
observed in honour of the gods of the netherworld) and added two days to 
Sextilis for a total of 31; January, March, May, Quintilis, October, and 
December also had 31 days, with 30 days for April, June, September, and 
November. The subsequent change of Sextilis to Augustus therefore 
involved no addition of days to the latter.

The Julian calendar retained the Roman republican calendar method of 
numbering the days of the month. Compared with the present system, the 
Roman numbering seems to run backward, for the first day of the month 
was known as the Kalendae, but subsequent days were not enumerated as so 
many after the Kalendae but as so many before the following Nonae 
(“nones”), the day called nonae being the ninth day before the Ides 
(from iduare, meaning “to divide”), which occurred in the middle of the 
month and were supposed to coincide with the Full Moon. Days after the 
Nonae and before the Ides were numbered as so many before the Ides, and 
those after the Ides as so many before the Kalendae of the next month.

It should be noted that there were no weeks in the original Julian 
calendar. The days were designated either dies fasti or dies nefasti, 
the former being business days and days on which the courts were open; 
this had been the practice in the Roman republican calendar. Julius 
Caesar designated his additional days all as dies fasti, and they were 
added at the end of the month so that there was no interference with the 
dates traditionally fixed for dies comitiales (days on which public 
assemblies might be convened) and dies festi and dies feriae (days for 
religious festivals and holy days). Originally, then, the Julian 
calendar had a permanent set of dates for administrative matters. The 
official introduction of the seven-day week by Emperor Constantine I in 
the 4th century ce disrupted this arrangement.

It appears, from the date of insertion of the intercalary month in the 
Roman republican calendar and the habit of designating years by the 
names of the consuls, that the calendar year had originally commenced in 
March, which was the date when the new consul took office. In 222 bce 
the date of assuming duties was fixed as March 15, but in 153 bce it was 
transferred to the Kalendae of January, and there it remained. January 
therefore became the first month of the year, and in the western region 
of the Roman Empire, this practice was carried over into the Julian 
calendar. In the eastern provinces, however, years were often reckoned 
from the accession of the reigning emperor, the second beginning on the 
first New Year’s day after the accession; and the date on which this 
occurred varied from one province to another.

[...]

On 23-02-2021 10:44, R.O. wrote:
>
> Xiuhpōhualli
>
> https://en.wikipedia.org/wiki/Xiuhp%C5%8Dhualli
>
>
>
>
> Reconstruction of the calendar
>
> For many centuries, scholars had tried to reconstruct the Calendar. 
> The latest and more-accepted version was proposed by professor Rafael 
> Tena (INAH),[3] based on the studies of Sahagún, Durán and Alfonso 
> Caso (UNAM). His correlation confirms that the mexica year started on 
> February 13th using the old Julian calendar or February 23rd of the 
> current Gregorian calendar.
> See also
>
> Aztec calendar
> Tianquiztli
>
> Notes
>
> "The Nemontemi and the Month Quahuitlehua in the Aztec Solar 
> Calendar". World Digital Library.
> The Mexica Calendar and the Cronography. Rafael Tena. INAH-CONACULTA. 
> 2008 p 82-83
>
> The Mexica Calendar and the Cronography. Rafael Tena. INAH-CONACULTA. 2008
>
> References
> Miller, Mary; Karl Taube (1993). The Gods and Symbols of Ancient 
> Mexico and the Maya. London: Thames and Hudson. ISBN 0-500-05068-6.
>
>
>
>
> aztecheaders
>
>
>
>
>
> On 23-02-2021 09:14, R.O. wrote:
>> aztecheaders
>>
>> _______________________________________________
>> D66 mailing list
>> D66 at tuxtown.net
>> http://www.tuxtown.net/mailman/listinfo/d66
>
> _______________________________________________
> D66 mailing list
> D66 at tuxtown.net
> http://www.tuxtown.net/mailman/listinfo/d66
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