by Formosus Viriustus on Fri Feb 27, 2009 2:30 am
Salve Omnes !
Doing some googling I found the following on wikipedia :
The Julian months were formed by adding ten days to a regular pre-Julian Roman year of 355 days, creating a regular Julian year of 365 days: Two extra days were added to Ianuarius, Sextilis (Augustus) and December, and one extra day was added to Aprilis, Iunius, September and November, setting the lengths of the months to the values they still hold today:
Before 45 BC : 29, 28 (leap years 23 or 24), 31, 29, 31, 29 , 31 , 29 , 29 , 31 , 29 , 29 (Intercalaris : leap years, 27 , inserted between shortened February and March)
Length as of 45 BC : 31 , 28 (leap years : 29 ), 31 , 30 , 31, 30 , 31 , 31 , 30 , 31 , 30 ; 31
The Julian reform set the lengths of the months to their modern values. However, a 13th century scholar, Sacrobosco, proposed a different explanation for the lengths of Julian months which is still widely repeated but is certainly wrong. According to Sacrobosco, the original scheme for the months in the Julian Calendar was very regular, alternately long and short. From January through December, the month lengths according to Sacrobosco for the Roman Republican calendar were:
30, 29, 30, 29, 30, 29, 30, 29, 30, 29, 30, 29
He then thought that Julius Caesar added one day to every month except February, a total of 11 more days, giving the year 365 days. A leap day could now be added to the extra short February:
31, 29/30, 31, 30, 31, 30, 31, 30, 31, 30, 31, 30
He then said Augustus changed this to:
31, 28/29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
so that the length of Augustus would not be shorter than (and therefore inferior to) the length of Iulius, giving us the irregular month lengths which are still in use.
There is abundant evidence disproving this theory. First, a wall painting of a Roman calendar predating the Julian reform has survived, which confirms the literary accounts that the months were already irregular before Julius Caesar reformed them:
29, 28, 31, 29, 31, 29, 31, 29, 29, 31, 29, 29
The Senatorial decree (senatus consultum) renaming Sextilis to Augustus reads in part:
"Whereas the Emperor Augustus Caesar, in the month of Sextilis, was first admitted to the consulate, and thrice entered the city in triumph, and in the same month the legions, from the Janiculum, placed themselves under his auspices, and in the same month Egypt was brought under the authority of the Roman people, and in the same month an end was put to the civil wars; and whereas for these reasons the said month is, and has been, most fortunate to this empire, it is hereby decreed by the senate that the said month shall be called Augustus." (8 BC)
So it is the Julian Calendar after all. But it was the Old Romans who were at least partly responsible for the 28-day-month and it had to do with lucky and unlucky numbers. Why Caesar stuck to it we may never know.
And it is the Sacrobosco-version I must have picked up somewhere years ago. How about that ? He wrote this in 'de Anni Ratione' (or 'Compotus') in 1235 CE. I find it remarkable that Sacrobosco assumed that the Republican Romans did use a solar-lunar calendar (alternating months of 29 and 30 days respectively). The system that was used by nearly everybody else in those days. And Sacrobosco was not a stupid man : he is supposed to be the first one to have noticed that by his time the Julian Calendar was off again by some ten days.
So, here's a wild idea : what if they both were right ? I have to dig into that a bit deeper, but I have seen somewhere that the Athenians had no less than five calendars, all for different aspects of life. I just can't get it out of my head that, certainly in a rural farming community the moon cycle was too important to neglect.
Any ideas on that ?
Yes, of cause, my Xanthippe has her own opinion on the subject. Does that surprise you ? But don't pay too much attention to her. She's not the sharpest tool in the shed.
Vale,