Re: Numbering of days within the Roman Interkalaris
Sent: Sunday, August 09, 2009 3:02 PM
Subject: Re: Numbering of days within the Roman
Interkalaris
Chris,
Thanks much for your correction and
explanation. A follow up question: is there an explanation for how the
Pontifex decided whether a 22-day or 23-day intercalation was
needed?
--Danny
Not really. Macrobius describes schemes
where 22 and 23 day intercalations alternated to maintain an average solar
year of the correct length, but so far as we can infer the actual distribution
of intercalations this discussion doesn't reflect reality, at least not in the
second and first centuries BC. For the third century, before the Second
Punic War, the data is consistent with a scheme of alternating lengths in
alternate years, but is not precise enough to allow us to verify
it.
I looked at the problem of converting
pre-Julian dates to Julian ones in a series of notes in the Zeitschrift fur
Papyrologie und Epigraphik. Based on second and first century epigraphic
and literary data, I concluded in an article titled
"Evidence for the Regulation of Intercalation under the
Lex Acilia" in ZPE 151 that almost all the
intercalations in that period were 378 days long, and that the number of
377-day intercalations before 55 BC was equal to the number of times
there were two successive intercalary years. I suggested a scheme,
probably created by the Lex Acilia of 191, whereby the pontiffs were
free to choose the length of the year subject to certain restrictions:
they were not supposed to allow more than 2 ordinary or more than 2
intercalary years in succession, but they could choose to intercalate in 2
consecutive years. If they did so the pair would be 377 and 378
days long. If there was to be only one intercalary year followed by an
ordinary year the intercalary year would be 378 days
long.
This system is consistent with all the data
we have for the second century and the first half of the first. I think
it started to break down in the 70s BC when an additional restriction --
formal or informal -- was added that it was desirable to avoid a market day on
Kal Ian. That eventually created a trap whereby they were forced to have
2 ordinary years followed an intercalary year repeatedly, which makes the
average year too short for the sun. The only way to break out of this
deadlock consistent with the inferred rules is to have a pair of
intercalary years, and I think Caesar, the pontifex maximus at the time, tried
to do that: 55 BC was certainly a 377-day intercalation. But
54 and 53 were ordinary years, causing 52 to start on such a market day.
Caesar was too busy massacring a million Gauls to bother sorting out this type
of arcana, so it's not surprising that he abandoned trying to intercalate at
all after 49 and eventually introduced what was, in effect, a whole new
calendar.
This particular reconstruction may or may not be
right, all I can say is that it's consistent with the contemporary evidence
given the structure of the calendar revealed by later accounts. But I
think the general picture of arbitrary choice subject to meeting certain
restrictions probably is.
HTH
Chris
