Discussion:
Roman calendar conversion table
(too old to reply)
Jim O'Donnell
2014-09-09 03:53:39 UTC
Permalink
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.

Jim O'Donnell
Lorenzo Smerillo
2014-09-09 04:28:23 UTC
Permalink
The issue is complex in that calendar references depend on astronomical
verification, and having a contemporary textual source close to the date
one is searching. My general impression is that intercalation was "fairly
regular" with notable exceptions: Punic wars and Caesar's absence from the
City when he was Pont. Max. (who had to do the intercalation in February).
But some sources and studies which go into greater and complex detail are
below. It is difficult to actually make a reference table for each year, as
evidence is vexed or lacking.

Evidence for the Regulation of Intercalation under the Lex Acilia
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 151 (2005), pp. 167-184
Stable URL: http://www.jstor.org/stable/20191985

Two Notes on the Chronology of the Late Republic
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 147 (2004), pp. 169-174
Stable URL: http://www.jstor.org/stable/20191812 .

Livy and the "Lex Hortensia": The Julian Chronology of the Comitial Dates
in Livy
Author(s): Chris BennettSource: Zeitschrift für Papyrologie und Epigraphik,
Bd. 149 (2004), pp. 165-176
Stable URL: http://www.jstor.org/stable/20191903 .

Denis Feeney, Caesar's Calendar, UCP, 2007: has lots in the footnotes.

R. Hannah, Greek and Roman calendars: Constructions of time in the
classical world, London, 2005:107-108.

A.K. Michels, The Calendar of the Roman Republic, Princeton, 1967:161.

feliciter.
Lorenzo Smerillo
Department of Classics and Humanities
Montclair State University
Montclair, NJ 07043
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
Lorenzo Smerillo
2014-09-09 05:10:11 UTC
Permalink
I would add that the (Republican) calendar is a civil and religious
instrument, not a time keeper as we think of it in our
Julian-Augustan-Gregorian matrix. Greeks and Romans, others too, were
quite capable and did use the stars, birds, weather and fauna, as
indications of time when to do (Hesiod). One of the reasons the
inauguration of the Consuls was moved from March to January in 153 BC was
so that they would have sufficient time to prepare an army for late spring
campaigns. It would have been obvious that this is the dead of winter, and
one does not need a calendar date to know that, but snow on the Prenestini
might have been a good hint to the need to intercalate. Nor does a farmer
need a calendar to tell him that it is summer (even if the out of phase
calendar says it's October). It is only the historian (or the propagandist)
who needs to record a calendar date, more often than not one that is in
someway or other significant in conjunction with the event described, as
Eratosthenes does with the Fall of Troy being A Thousand Years before
Alexander (as Finney points out). That commemorative function becomes much
easier with the J-A-G calendar.

One of the best and surest ways of matching pre-Julian datings in the
Republican calendar to Julian dates is by eclipses, not solstices or
aequinoces, as is clear from Bennett's work: it is very painstaking.

feliciter.
LS
Post by Lorenzo Smerillo
The issue is complex in that calendar references depend on astronomical
verification, and having a contemporary textual source close to the date
one is searching. My general impression is that intercalation was "fairly
regular" with notable exceptions: Punic wars and Caesar's absence from the
City when he was Pont. Max. (who had to do the intercalation in February).
But some sources and studies which go into greater and complex detail are
below. It is difficult to actually make a reference table for each year, as
evidence is vexed or lacking.
Evidence for the Regulation of Intercalation under the Lex Acilia
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 151 (2005), pp. 167-184
Stable URL: http://www.jstor.org/stable/20191985
Two Notes on the Chronology of the Late Republic
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 147 (2004), pp. 169-174
Stable URL: http://www.jstor.org/stable/20191812 .
Livy and the "Lex Hortensia": The Julian Chronology of the Comitial Dates
in Livy
Author(s): Chris BennettSource: Zeitschrift für Papyrologie und
Epigraphik, Bd. 149 (2004), pp. 165-176
Stable URL: http://www.jstor.org/stable/20191903 .
Denis Feeney, Caesar's Calendar, UCP, 2007: has lots in the footnotes.
R. Hannah, Greek and Roman calendars: Constructions of time in the
classical world, London, 2005:107-108.
A.K. Michels, The Calendar of the Roman Republic, Princeton, 1967:161.
feliciter.
Lorenzo Smerillo
Department of Classics and Humanities
Montclair State University
Montclair, NJ 07043
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
James Spinti
2014-09-09 05:22:52 UTC
Permalink
I relatively recently read a delightful book on calendars in the ANE:
Poetic Astronomy in the Ancient Near East: The Reflexes of Celestial
Science in Ancient Mesopotamian, Ugaritic, and Israelite Narrative. He
discusses the calendar as a civil/religious instrument at length. My
favorite:
The celestial diviners who employed the Ideal Calendar were perfectly
aware of this fact and relied on it to generate calendrical anomalies
that were considered ominous. Though it was modeled on an idealized
concept of time division, this did not mean it could not be modified.
When intercalation schemes, for example, are mentioned in celestial
divination texts, they have little practical calendrical value and
instead tend to reference the aversion of a bad portent by changing the
month in which it took place. For example, the namburbî ritual involving
intercalation described in The Diviner’s Manual 66–71 is specifically
designed to avert evil rather than properly align the lunar and tropical
calendars.—Poetic Astronomy in the Ancient Near East, pages 30-31,
footnote

Creative use isn't it? : ) No wonder historians get gray hairs!

James
_______________________
James Spinti
Proofreading and copyediting of ancient Near Eastern and biblical
studies monographs
E-mail: jdspinti at gmail dot com
Phone: 260-445-3118
PO Box 791
Grand Marais MN 55604



------ Original Message ------
From: "Lorenzo Smerillo" <***@gmail.com>
To: CLASSICS-***@lsv.uky.edu
Sent: 9/9/2014 12:10:11 AM
Subject: Re: [CLASSICS-L] Roman calendar conversion table
Post by Lorenzo Smerillo
I would add that the (Republican) calendar is a civil and religious
instrument, not a time keeper as we think of it in our
Julian-Augustan-Gregorian matrix. Greeks and Romans, others too, were
quite capable and did use the stars, birds, weather and fauna, as
indications of time when to do (Hesiod). One of the reasons the
inauguration of the Consuls was moved from March to January in 153 BC was
so that they would have sufficient time to prepare an army for late spring
campaigns. It would have been obvious that this is the dead of winter, and
one does not need a calendar date to know that, but snow on the
Prenestini
might have been a good hint to the need to intercalate. Nor does a farmer
need a calendar to tell him that it is summer (even if the out of phase
calendar says it's October). It is only the historian (or the
propagandist)
who needs to record a calendar date, more often than not one that is in
someway or other significant in conjunction with the event described, as
Eratosthenes does with the Fall of Troy being A Thousand Years before
Alexander (as Finney points out). That commemorative function becomes much
easier with the J-A-G calendar.
One of the best and surest ways of matching pre-Julian datings in the
Republican calendar to Julian dates is by eclipses, not solstices or
aequinoces, as is clear from Bennett's work: it is very painstaking.
feliciter.
LS
Post by Lorenzo Smerillo
The issue is complex in that calendar references depend on
astronomical
verification, and having a contemporary textual source close to the date
one is searching. My general impression is that intercalation was "fairly
regular" with notable exceptions: Punic wars and Caesar's absence from the
City when he was Pont. Max. (who had to do the intercalation in February).
But some sources and studies which go into greater and complex
detail are
below. It is difficult to actually make a reference table for each year, as
evidence is vexed or lacking.
Evidence for the Regulation of Intercalation under the Lex Acilia
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 151 (2005), pp. 167-184
Stable URL: http://www.jstor.org/stable/20191985
Two Notes on the Chronology of the Late Republic
Author(s): Chris Bennett Source: Zeitschrift für Papyrologie und
Epigraphik, Bd. 147 (2004), pp. 169-174
Stable URL: http://www.jstor.org/stable/20191812 .
Livy and the "Lex Hortensia": The Julian Chronology of the Comitial Dates
in Livy
Author(s): Chris BennettSource: Zeitschrift für Papyrologie und
Epigraphik, Bd. 149 (2004), pp. 165-176
Stable URL: http://www.jstor.org/stable/20191903 .
Denis Feeney, Caesar's Calendar, UCP, 2007: has lots in the
footnotes.
R. Hannah, Greek and Roman calendars: Constructions of time in the
classical world, London, 2005:107-108.
A.K. Michels, The Calendar of the Roman Republic, Princeton,
1967:161.
feliciter.
Lorenzo Smerillo
Department of Classics and Humanities
Montclair State University
Montclair, NJ 07043
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
David Meadows
2014-09-09 09:37:58 UTC
Permalink
Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
David Meadows
2014-09-09 09:46:22 UTC
Permalink
This is an important question but I think it's more or less un answerable. For the most part, the roman calendar without intercalations would be out of whack by about ten days a year. Ceteris paribus, that would suggest that at the time of jc's reform, it was almost an entire season off. If that was the 'reset', that only gets you back to the mid 50s .. We would need to know how conscientious previous pms were at doing the reset, especially the month, but one could in theory reverse engineer the resets

DM

Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
Jim O'Donnell
2014-09-09 20:50:00 UTC
Permalink
With thanks to all -- I would settle for a listing that showed (a) how
many days were in each year (i.e., whether intercalated or not) and
(b) the Julian date for 1 January for that year or close approximation
-- or the date on which the spring equinox fell or the summer
solstice. This is a question for the historian not interested in
calendar or other but who just wants to know for a given year how far
the calendrical dates were out of line with the heavens. When Caesar
is in Gaul (my interest), the year started *approximately* two months
late, so the equinox didn't come until May. I'd be glad to have a
more precise estimate year-by-year. I'll go rootle again in Feeney's
footnotes, but I fear he's not interested in that either. (It would
also help for astronomical events -- we know a lot about dates of
eclipses, phases of the moon, etc., but before 46 BCE it's hard to
coordinate what the astronomers can tell us now with what we get in
texts.)

jo'd
Post by David Meadows
This is an important question but I think it's more or less un answerable. For the most part, the roman calendar without intercalations would be out of whack by about ten days a year. Ceteris paribus, that would suggest that at the time of jc's reform, it was almost an entire season off. If that was the 'reset', that only gets you back to the mid 50s .. We would need to know how conscientious previous pms were at doing the reset, especially the month, but one could in theory reverse engineer the resets
DM
Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
David Meadows
2014-09-09 21:02:48 UTC
Permalink
this is interesting to me... I ll poke around a bit as well and
Post by Jim O'Donnell
With thanks to all -- I would settle for a listing that showed (a) how
many days were in each year (i.e., whether intercalated or not) and
(b) the Julian date for 1 January for that year or close approximation
-- or the date on which the spring equinox fell or the summer
solstice. This is a question for the historian not interested in
calendar or other but who just wants to know for a given year how far
the calendrical dates were out of line with the heavens. When Caesar
is in Gaul (my interest), the year started *approximately* two months
late, so the equinox didn't come until May. I'd be glad to have a
more precise estimate year-by-year. I'll go rootle again in Feeney's
footnotes, but I fear he's not interested in that either. (It would
also help for astronomical events -- we know a lot about dates of
eclipses, phases of the moon, etc., but before 46 BCE it's hard to
coordinate what the astronomers can tell us now with what we get in
texts.)
jo'd
On Tue, Sep 9, 2014 at 5:46 AM, David Meadows
Post by David Meadows
This is an important question but I think it's more or less un
answerable. For the most part, the roman calendar without
intercalations would be out of whack by about ten days a year. Ceteris
paribus, that would suggest that at the time of jc's reform, it was
almost an entire season off. If that was the 'reset', that only gets
you back to the mid 50s .. We would need to know how conscientious
previous pms were at doing the reset, especially the month, but one
could in theory reverse engineer the resets
Post by David Meadows
DM
Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in
March,
Post by David Meadows
Post by Jim O'Donnell
it's fairly easy to tell what that means in terms of climate.
Before
Post by David Meadows
Post by Jim O'Donnell
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would
occur
Post by David Meadows
Post by Jim O'Donnell
more or less in late March) but in fact intercalations were missed
and
Post by David Meadows
Post by Jim O'Donnell
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15
March
Post by David Meadows
Post by Jim O'Donnell
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left
his
Post by David Meadows
Post by Jim O'Donnell
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
Ivan Van Laningham
2014-09-09 21:06:10 UTC
Permalink
Hi All, Jim--
I suspect that this may help:

http://books.google.com/books?id=J54NAAAAQAAJ&pg=PA513&lpg=PA513&dq=intercalation+roman+calendar&source=bl&ots=o0GKgFhp30&sig=-ox0WFRn1fRTiUOkDmJGN_qlPvc&hl=en&sa=X&ei=wGMPVIq0FuiLjAK68oGQCw&ved=0CGMQ6AEwCQ#v=onepage&q=intercalation%20roman%20calendar&f=false

Although you will require more patience than with which I am so equipped
(and I am a card-carrying calendar freak): the table of contents is to be
found following page cxxxv of the preliminary material, and covers the
entire four volumes, each of which is divided into Disertations. Volume
III may reward you.

Metta,
Ivan
Post by Jim O'Donnell
With thanks to all -- I would settle for a listing that showed (a) how
many days were in each year (i.e., whether intercalated or not) and
(b) the Julian date for 1 January for that year or close approximation
-- or the date on which the spring equinox fell or the summer
solstice. This is a question for the historian not interested in
calendar or other but who just wants to know for a given year how far
the calendrical dates were out of line with the heavens. When Caesar
is in Gaul (my interest), the year started *approximately* two months
late, so the equinox didn't come until May. I'd be glad to have a
more precise estimate year-by-year. I'll go rootle again in Feeney's
footnotes, but I fear he's not interested in that either. (It would
also help for astronomical events -- we know a lot about dates of
eclipses, phases of the moon, etc., but before 46 BCE it's hard to
coordinate what the astronomers can tell us now with what we get in
texts.)
jo'd
Post by David Meadows
This is an important question but I think it's more or less un
answerable. For the most part, the roman calendar without intercalations
would be out of whack by about ten days a year. Ceteris paribus, that would
suggest that at the time of jc's reform, it was almost an entire season
off. If that was the 'reset', that only gets you back to the mid 50s .. We
would need to know how conscientious previous pms were at doing the reset,
especially the month, but one could in theory reverse engineer the resets
Post by David Meadows
DM
Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
Mark Davidson
2014-09-10 04:58:17 UTC
Permalink
Jim, I think this may be the kind of table you are looking for.

Intro page
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/chron_rom_intro_fr.htm

The table itself
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/roman_civil.htm

Key to reading the table
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/chron_rom_howto_fr.htm

It's probably more readable if it's downloaded as an Excel spreadsheet.

It seems to be well sourced, with lots of notes.

According to this analysis, during the period 58-50 BCE the discrepancy was
less than I would have expected, about 2-7 weeks.

Mark
david meadows
2014-09-10 09:32:14 UTC
Permalink
A problem i have always had with Julius Caesar's intercalations is knowing
whether the people of Rome actually lived through additional days or
whether the changed was done 'on paper', as it were. Unless JC knew what
day it was *supposed* to be when the end of February came along (which is
possible with his Egyptian connections and/or possibly some sort of
Antikythera mechanism device) it seems to me the 'practical' way for him to
do things would be to wait until the equinox and/or solstice and just
'change the date' with the additional days essentially being done pro
forma. It would probably be much less disruptive to everyday life.
Post by Mark Davidson
Jim, I think this may be the kind of table you are looking for.
Intro page
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/chron_rom_intro_fr.htm
The table itself
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/roman_civil.htm
Key to reading the table
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/chron_rom_howto_fr.htm
It's probably more readable if it's downloaded as an Excel spreadsheet.
It seems to be well sourced, with lots of notes.
According to this analysis, during the period 58-50 BCE the discrepancy was
less than I would have expected, about 2-7 weeks.
Mark
Mark Davidson
2014-09-10 10:23:40 UTC
Permalink
Post by david meadows
A problem i have always had with Julius Caesar's intercalations is
knowing whether the people of Rome actually lived through additional
days or whether the changed was done 'on paper', as it were. Unless JC
knew what day it was *supposed* to be when the end of February came
along (which is possible with his Egyptian connections and/or possibly
some sort of Antikythera mechanism device) it seems to me the
'practical' way for him to do things would be to wait until the equinox
and/or solstice and just 'change the date' with the additional days
essentially being done pro forma. It would probably be much less
disruptive to everyday life.
No, he was ADDING days, not subtracting.

If you are subtracting days then you can just adjust the calendar date, as
was done in Britain (and America) in 1752. September 2, 1752 was followed
by September 14, 1752 - an 11 day adjustment from the Julian to the
Gregorian calendar.

But if you are adding additional days, as Caesar did, then if you were to
simply change the date, you would be changing the date BACK to an earlier
date, and you would have duplicate dates. That's why an intercalary period
was inserted.

Mark
david meadows
2014-09-10 11:13:46 UTC
Permalink
But it *is* adding, or more properly, intercalating ... imagine this
scenario ... the calendar has not been intercalated for years. Every year
it's five or so days off. So in year one the solstice lands on June 21 ...
the next year it's June 16th ... the next year it's June 11th and so on.
Eventually you get to a situation where a solstice (or an equinox) lands on
the date you usually intercalate or come close to it. if you simply say
February 21 (when the solstice is actually happening) is June 21 (when it
should be happening) you have not gone back to an earlier date ...
Post by Mark Davidson
Post by david meadows
A problem i have always had with Julius Caesar's intercalations is
knowing whether the people of Rome actually lived through additional
days or whether the changed was done 'on paper', as it were. Unless JC
knew what day it was *supposed* to be when the end of February came
along (which is possible with his Egyptian connections and/or possibly
some sort of Antikythera mechanism device) it seems to me the
'practical' way for him to do things would be to wait until the equinox
and/or solstice and just 'change the date' with the additional days
essentially being done pro forma. It would probably be much less
disruptive to everyday life.
No, he was ADDING days, not subtracting.
If you are subtracting days then you can just adjust the calendar date, as
was done in Britain (and America) in 1752. September 2, 1752 was followed
by September 14, 1752 - an 11 day adjustment from the Julian to the
Gregorian calendar.
But if you are adding additional days, as Caesar did, then if you were to
simply change the date, you would be changing the date BACK to an earlier
date, and you would have duplicate dates. That's why an intercalary period
was inserted.
Mark
Mark Davidson
2014-09-10 11:33:03 UTC
Permalink
Post by david meadows
But it *is* adding, or more properly, intercalating ... imagine this
scenario ... the calendar has not been intercalated for years. Every
year it's five or so days off. So in year one the solstice lands on
June 21 ... the next year it's June 16th ... the next year it's June
11th and so on. Eventually you get to a situation where a solstice (or
an equinox) lands on the date you usually intercalate or come close to
it. if you simply say February 21 (when the solstice is actually
happening) is June 21 (when it should be happening) you have not gone
back to an earlier date ...
No, it's the other way round.

If you don't insert the necessary intercalary months, then the calendar
year will be too short. If the calendar year is too short, then the
calendar date will be June 21 *before* the solstice, and the so the
solstice will fall on a later date. The solstice will be June 26, July 1,
etc.

What Caesar was doing, in effect, was inserting all the missed intercalary
periods in one go.

Mark
David Meadows
2014-09-10 11:51:55 UTC
Permalink
I think we're saying the same thing... but did they actually live through a year that was 400+ days or was it done 'on paper' when a fixed date like the solstice came around
Post by Mark Davidson
Post by david meadows
But it *is* adding, or more properly, intercalating ... imagine this
scenario ... the calendar has not been intercalated for years. Every
year it's five or so days off. So in year one the solstice lands on
June 21 ... the next year it's June 16th ... the next year it's June
11th and so on. Eventually you get to a situation where a solstice
(or
Post by david meadows
an equinox) lands on the date you usually intercalate or come close
to
Post by david meadows
it. if you simply say February 21 (when the solstice is actually
happening) is June 21 (when it should be happening) you have not gone
back to an earlier date ...
No, it's the other way round.
If you don't insert the necessary intercalary months, then the calendar
year will be too short. If the calendar year is too short, then the
calendar date will be June 21 *before* the solstice, and the so the
solstice will fall on a later date. The solstice will be June 26, July 1,
etc.
What Caesar was doing, in effect, was inserting all the missed
intercalary
periods in one go.
Mark
--
Sent from my Android device with K-9 Mail. Please excuse my brevity.
Mark Davidson
2014-09-10 12:57:10 UTC
Permalink
Post by David Meadows
... but did they actually live through a year that was 400+ days or was
it done 'on paper' when a fixed date like the solstice came around
Yes, they actually did live through a long year.

If you look at the table
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/roman_civil.htm

at the line for 47 BC (in the first column), just above the solid blue line
indicating the start of Caesar's reform, the Julian date for the first day
of the Roman year 708 AUC is shown as 12-Oct.

In that Roman year there were two intercalations (grey columns) of 23 days
in Feb and 67 days between Nov and Dec. Making that Roman year 445 days
long.

So that year, which we tend to think of as 46 BC, actually started on Oct
12, 47 BC. And the following Roman year, the first of the official Julian
calendar - which we think of as 45 BC - actually started a day early on Dec
31, 46 BC.

i.e. The Roman year 708 AUC ran from the Julian dates
Oct 12, 47 BC - Dec 30, 46 BC

So it really was a year of 445 days.

Mark
Patrick Rourke
2014-09-10 14:19:38 UTC
Permalink
You'd either have to intercalate days or wait for the failed intercalation
to cycle around and then arbitrarily "adjust" the year. If I understand
David correctly, it's this latter approach that he has in mind: wait for
the modulus to rise above 183 and then skip days instead of intercalating
them.

The problem is that if you waited for the failed intercalation to cycle
around, you'd have anomalies in your year spans. Basically, you'd have a
lot of 32 year olds who were being called 33 year olds.

It would also mean the AUC date would be off by a year. This might not be a
problem since the AUC dates weren't established in the Republican period
and weren't that widely used anyway (and if the Wikipedia article is any
guide, the Varronian chronology has its problems, anyway).

I think the point is that if you aren't counting years consecutively (if
e.g. your years are designated by a sequence of consulships), a modular
"wrap-around" instead of an intercalation might be feasible. But I don't
think that's what Caesar did.

Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were often
overly generous to extend officials' terms of office.
Post by Mark Davidson
Post by David Meadows
... but did they actually live through a year that was 400+ days or was
it done 'on paper' when a fixed date like the solstice came around
Yes, they actually did live through a long year.
If you look at the table
http://www.www.tyndalehouse.com/Egypt/ptolemies/chron/roman/roman_civil.htm
at the line for 47 BC (in the first column), just above the solid blue line
indicating the start of Caesar's reform, the Julian date for the first day
of the Roman year 708 AUC is shown as 12-Oct.
In that Roman year there were two intercalations (grey columns) of 23 days
in Feb and 67 days between Nov and Dec. Making that Roman year 445 days
long.
So that year, which we tend to think of as 46 BC, actually started on Oct
12, 47 BC. And the following Roman year, the first of the official Julian
calendar - which we think of as 45 BC - actually started a day early on Dec
31, 46 BC.
i.e. The Roman year 708 AUC ran from the Julian dates
Oct 12, 47 BC - Dec 30, 46 BC
So it really was a year of 445 days.
Mark
--
Patrick Rourke
ptrourke [(at)] methymna.com
Mark Davidson
2014-09-10 15:11:06 UTC
Permalink
Post by Patrick Rourke
Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were
often overly generous to extend officials' terms of office.
Assuming that Chris Bennett's table is accurate, you can find that
information there.

Actually it doesn't look too bad. It seems that it's only from the mid-50s
BC that things started going awry, and only during the Civil War that it
became bad. And then it's all in the direction of intercalations left out,
not extra ones added - presumably because it was up to Caesar as Pontifex
Maximus to insert the intercalations.

Mark
Ivan Van Laningham
2014-09-16 21:22:11 UTC
Permalink
Hi All--
I was intrigued by the spreadsheet, and the associated website, that Mark
Davidson posted. The spreadsheet (roman_civil.xls) seemed to include
everything I needed to implement a detailed, and accurate, rendition of the
Roman Calendar from 263 BCE to 60CE. Since Mark posted the links to Chris
Bennett's website, I've been busy doing just that (using Python, of course,
if anyone cares).

In the process, I found a typo. Line 33, which begins with 233BC/521AUC
should be 232BC. Left at 233BC, that would mean that the Varronian year
521 would have begun a year before the previous year ended, a condition
obviously untrue.

So I wrote to Chris, hoping he would make a correction (incidentally, that
was the *only *typo I found in the entire table; I was impressed).
However, I almost immediately received a notification. "The owner of this
email address, Chris Bennett, has died. Please remove it from your address
book."

That's very sad news.

Metta,
Ivan
Post by Mark Davidson
Post by Patrick Rourke
Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were
often overly generous to extend officials' terms of office.
Assuming that Chris Bennett's table is accurate, you can find that
information there.
Actually it doesn't look too bad. It seems that it's only from the mid-50s
BC that things started going awry, and only during the Civil War that it
became bad. And then it's all in the direction of intercalations left out,
not extra ones added - presumably because it was up to Caesar as Pontifex
Maximus to insert the intercalations.
Mark
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
Gent, R.H. van (Rob)
2014-09-17 08:17:01 UTC
Permalink
Hi,

For some information on the creator of the Roman calendar conversion spreadsheet who sadly passed away nine months ago, see

http://www.legacy.com/obituaries/utsandiego/obituary.aspx?n=christopher-john-bennett&pid=169165351

I too have been using his spreadsheet to create an online Roman calendar conversion tool which I soon hope make available.

Rob van Gent
Department of Mathematics
Utrecht University

-----Original Message-----
From: Classical Greek and Latin Discussion Group [mailto:CLASSICS-***@LSV.UKY.EDU] On Behalf Of Ivan Van Laningham
Sent: dinsdag 16 september 2014 23:22
To: CLASSICS-***@LSV.UKY.EDU
Subject: Re: [CLASSICS-L] Roman calendar conversion table

Hi All--
I was intrigued by the spreadsheet, and the associated website, that Mark Davidson posted. The spreadsheet (roman_civil.xls) seemed to include everything I needed to implement a detailed, and accurate, rendition of the Roman Calendar from 263 BCE to 60CE. Since Mark posted the links to Chris Bennett's website, I've been busy doing just that (using Python, of course, if anyone cares).

In the process, I found a typo. Line 33, which begins with 233BC/521AUC should be 232BC. Left at 233BC, that would mean that the Varronian year
521 would have begun a year before the previous year ended, a condition obviously untrue.

So I wrote to Chris, hoping he would make a correction (incidentally, that was the *only *typo I found in the entire table; I was impressed).
However, I almost immediately received a notification. "The owner of this email address, Chris Bennett, has died. Please remove it from your address book."

That's very sad news.

Metta,
Ivan
Post by Mark Davidson
Post by Patrick Rourke
Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were
often overly generous to extend officials' terms of office.
Assuming that Chris Bennett's table is accurate, you can find that
information there.
Actually it doesn't look too bad. It seems that it's only from the
mid-50s BC that things started going awry, and only during the Civil
War that it became bad. And then it's all in the direction of
intercalations left out, not extra ones added - presumably because it
was up to Caesar as Pontifex Maximus to insert the intercalations.
Mark
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python
Ivan Van Laningham
2014-09-17 14:35:19 UTC
Permalink
Thanks, Rob. Interesting fellow. Very sad.

Metta,
Ivan
Post by Gent, R.H. van (Rob)
Hi,
For some information on the creator of the Roman calendar conversion
spreadsheet who sadly passed away nine months ago, see
http://www.legacy.com/obituaries/utsandiego/obituary.aspx?n=christopher-john-bennett&pid=169165351
I too have been using his spreadsheet to create an online Roman calendar
conversion tool which I soon hope make available.
Rob van Gent
Department of Mathematics
Utrecht University
-----Original Message-----
Sent: dinsdag 16 september 2014 23:22
Subject: Re: [CLASSICS-L] Roman calendar conversion table
Hi All--
I was intrigued by the spreadsheet, and the associated website, that Mark
Davidson posted. The spreadsheet (roman_civil.xls) seemed to include
everything I needed to implement a detailed, and accurate, rendition of the
Roman Calendar from 263 BCE to 60CE. Since Mark posted the links to Chris
Bennett's website, I've been busy doing just that (using Python, of course,
if anyone cares).
In the process, I found a typo. Line 33, which begins with 233BC/521AUC
should be 232BC. Left at 233BC, that would mean that the Varronian year
521 would have begun a year before the previous year ended, a condition obviously untrue.
So I wrote to Chris, hoping he would make a correction (incidentally, that
was the *only *typo I found in the entire table; I was impressed).
However, I almost immediately received a notification. "The owner of this
email address, Chris Bennett, has died. Please remove it from your address
book."
That's very sad news.
Metta,
Ivan
Post by Mark Davidson
Post by Patrick Rourke
Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were
often overly generous to extend officials' terms of office.
Assuming that Chris Bennett's table is accurate, you can find that
information there.
Actually it doesn't look too bad. It seems that it's only from the
mid-50s BC that things started going awry, and only during the Civil
War that it became bad. And then it's all in the direction of
intercalations left out, not extra ones added - presumably because it
was up to Caesar as Pontifex Maximus to insert the intercalations.
Mark
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
Patrick Rourke
2014-09-17 14:39:38 UTC
Permalink
I had thought of doing exactly the same thing as Ivan.
Post by Ivan Van Laningham
Thanks, Rob. Interesting fellow. Very sad.
Metta,
Ivan
Post by Gent, R.H. van (Rob)
Hi,
For some information on the creator of the Roman calendar conversion
spreadsheet who sadly passed away nine months ago, see
http://www.legacy.com/obituaries/utsandiego/obituary.aspx?n=christopher-john-bennett&pid=169165351
Post by Gent, R.H. van (Rob)
I too have been using his spreadsheet to create an online Roman calendar
conversion tool which I soon hope make available.
Rob van Gent
Department of Mathematics
Utrecht University
-----Original Message-----
Sent: dinsdag 16 september 2014 23:22
Subject: Re: [CLASSICS-L] Roman calendar conversion table
Hi All--
I was intrigued by the spreadsheet, and the associated website, that Mark
Davidson posted. The spreadsheet (roman_civil.xls) seemed to include
everything I needed to implement a detailed, and accurate, rendition of
the
Post by Gent, R.H. van (Rob)
Roman Calendar from 263 BCE to 60CE. Since Mark posted the links to
Chris
Post by Gent, R.H. van (Rob)
Bennett's website, I've been busy doing just that (using Python, of
course,
Post by Gent, R.H. van (Rob)
if anyone cares).
In the process, I found a typo. Line 33, which begins with 233BC/521AUC
should be 232BC. Left at 233BC, that would mean that the Varronian year
521 would have begun a year before the previous year ended, a condition
obviously untrue.
So I wrote to Chris, hoping he would make a correction (incidentally,
that
Post by Gent, R.H. van (Rob)
was the *only *typo I found in the entire table; I was impressed).
However, I almost immediately received a notification. "The owner of
this
Post by Gent, R.H. van (Rob)
email address, Chris Bennett, has died. Please remove it from your
address
Post by Gent, R.H. van (Rob)
book."
That's very sad news.
Metta,
Ivan
Post by Mark Davidson
Post by Patrick Rourke
Which was more common - missed intercalations, or over-generous
intercalations? I was under the impression that intercalations were
often overly generous to extend officials' terms of office.
Assuming that Chris Bennett's table is accurate, you can find that
information there.
Actually it doesn't look too bad. It seems that it's only from the
mid-50s BC that things started going awry, and only during the Civil
War that it became bad. And then it's all in the direction of
intercalations left out, not extra ones added - presumably because it
was up to Caesar as Pontifex Maximus to insert the intercalations.
Mark
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Post by Gent, R.H. van (Rob)
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
--
Ivan Van Laningham
God N Locomotive Works
http://www.pauahtun.org/
http://www.python.org/workshops/1998-11/proceedings/papers/laningham/laningham.html
Army Signal Corps: Cu Chi, Class of '70
Author: Teach Yourself Python in 24 Hours
--
Patrick Rourke
ptrourke [(at)] methymna.com
Barry H.
2014-09-24 11:20:17 UTC
Permalink
Of interest to some, I'm sure:

https://www.facebook.com/groups/11404207692/permalink/10152244610942693/
--
N.E. Barry Hofstetter


My opinions in this message are my
own, and reflect no institution with
which I may be affiliated
Barry H.
2014-09-24 12:29:09 UTC
Permalink
Post by Barry H.
https://www.facebook.com/groups/11404207692/permalink/10152244610942693/
I had meant to include the full text of the article:

Pressrelease from DeMoss:
Undergraduate Students with Green Scholars Initiative Find
1,500-Year-Old Drawings of Constellations Hidden in Ancient Biblical
Manuscript

OKLAHOMA CITY, Sept. 19, 2014—

Museum of the Bible announced today that undergraduate students with its
Green Scholars Initiative have discovered what may be among the
earliest-known classical drawings of celestial constellations hidden
under a layer of Greek text in a 1,500-year-old biblical manuscript.
Additionally, the student-scholars at Tyndale House, an institution
associated with the University of Cambridge, found the earliest
manuscript attributed to Eratosthenes in the same document. The Greek
mathematician, geographer and astronomer was the first to calculate the
Earth’s circumference, the tilt of its axis and the inventor of geography.

The research, conducted in 2012 and 2013 at Cambridge, also uncovered
the earliest copy of the opening of a work by Aratus, a Greek poet who
was one of the first to write about constellations and other celestial
phenomena.

The discoveries were made as students used high-tech, multispectral
imaging on the Codex Climaci Rescriptus, an ancient codex purchased in
2009 as part of the Green Collection, one of the world’s largest private
collections of rare biblical texts and artifacts. This is a palimpsest
manuscript, meaning the writing underneath was rubbed out and written
over as ancient scribes repurposed costly parchment in order to create a
new document.

“Twenty sides of this manuscript were so well rubbed out that no one has
been able to read them for more than a thousand years,” said Dr. Jerry
Pattengale, executive director of the Green Scholars Initiative. “We
have consulted with Dr. Kristen Lippincott, a specialist in the history
of astronomical images, and she has confirmed that while our conclusions
are preliminary and warrant further research, there appears to be a
connection between the two drawings found and the constellations of
Taurus and Pleiades.”

In 2012, the Green Scholars Initiative entrusted publication of the
manuscript to Dr. Peter Williams, a specialist in Aramaic texts who has
mentored many promising scholars during the past two decades. Four
undergrad students, studying under Williams’ instruction, helped to make
these discoveries. The students are all theology majors at different
United Kingdom universities and were Green Scholars participating in
summer internships at Tyndale House at the time of the research. The
same year, University of Cambridge student Jamie Klair, then just 20
years old, made the first breakthrough when he found writing by the
astronomer and poet Aratus. The next summer, he was joined by University
of Manchester’s Jacob Madin, King’s College London’s Elspeth Barnett and
University of St. Andrews’ Simeon Burke in further deciphering the text
and recognizing drawings of constellations.
“The students on this project didn’t make the discovery of important
astronomical texts despite being only 20 to 22 years old. They made the
discoveries because of their age," said Williams. “No senior scholar
would have had the time or patience to try to read the manuscript’s
underwriting, which had been so thoroughly erased.”
Previous research on the Codex Climaci Rescriptus uncovered biblical
texts from the fifth to ninth centuries CE—texts comprising the world's
largest historical body of Christian Palestinian Aramaic, a dialect
close to the language Jesus spoke in his time. The manuscript has become
a scholar’s feast as almost every page has two layers of writing, Syriac
written on top of Aramaic or Greek. By using advanced imaging techniques
developed at Oxford, contemporary scholars have been better able to
research what is underneath the top layer of visible text.

The Green Scholars Initiative has gained notice for turning the academic
research paradigm on its head by allowing young scholars access to
ancient historical texts in collaboration with established
scholar-mentors, a practice largely unheard of in higher education.
Together, these Green Scholars are pioneering groundbreaking research on
the Green Collection

Full research on the Codex Climaci Rescriptus is due to be published in
2015 by Dutch academic publisher Brill, as part of a new series
dedicated to publication of items that are part of the Green Collection.
--
N.E. Barry Hofstetter


My opinions in this message are my
own, and reflect no institution with
which I may be affiliated
David Meadows
2014-09-09 09:50:52 UTC
Permalink
As a follow up, considering the evidence that we have the date of Vesuvius wrong, I've often wondered if there were calendar problems in pliny's day...

Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
David Meadows
2014-09-09 09:53:06 UTC
Permalink
... Sorry ... Hit send too fast ... E.g, what effect did the events of 69 have on calendar matters?

Sent from my iPad
Post by Jim O'Donnell
Caesar in 46 intercalated the usual intercalary month, then 67 more
days, to produce a year of 445 days and install the 365.25 day year.
From that point forward, when a Roman general does something in March,
it's fairly easy to tell what that means in terms of climate. Before
that, not so: the intercalary system, well-managed, could have kept
them pretty close to modern equivalences (when the equinox would occur
more or less in late March) but in fact intercalations were missed and
things slipped. What I'm looking for is a reference that would show
the Julian equivalent dates for the calendar years of at least the
earlier first century BCE -- that would let me ask when it's 15 March
"local time" in 62 BCE, what Julian date would that be? It's a
material question for things like the season at which Caesar left his
troops in winter quarters and when he returned. References sought.
Jim O'Donnell
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