|This article is of interest to the following WikiProjects:|
|This article is written in British English (colour, realise, travelled), and some terms used in it are different or absent from other varieties of English. According to the relevant style guide, this should not be changed without broad consensus.|
|A fact from this article was featured on Wikipedia's Main Page in the On this day... section on January 1, 2011.|
- 1 Utterly confusing copy
- 2 What's the difference?
- 3 Fence post error?
- 4 Is it possible to simplify the text?
- 5 Error in Dating
- 6 Edits by Xact
- 7 In need of Rewrite
- 8 Edit request from Damienpryan1, 19 August 2011
- 9 Edit request on 21 December 2011
- 10 Edit request for "Motivation"
- 11 Sacrobosco's theory on month lengths
- 12 Hostility to southern hemisphere residents
- 13 Edit request on 26 April 2012
- 14 Edit request on 26 April 2012
- 15 Edit request on 27 April 2012
- 16 Edit Request on 6 October 2012
- 17 Month name questions & new year
- 18 What was the Julian calendar aligned to?
- 19 Error in comparison of Julian and Gregorian dates in the lead text
- 20 Edit request on 16 September 2013
- 21 Egyptian calendar
- 22 First Aligned Day must be wrong
- 23 RFC: Is the Julian a reform of Egyptian calendar?
Utterly confusing copy
The second paragraph suggests the Roman, not the Julian, calendar was introduced by Caesar. Neither does it explicitly explain the name - ie, Julian after Julius. — Preceding unsigned comment added by 188.8.131.52 (talk) 13:46, 18 December 2012 (UTC)
What's the difference?
I just read a lot of this article but I still don't understand what the difference is between the Julian calendar and the Gregorian calendar. It sounds like they have the same number of days, the same number of months, the same names for the months and even the same arrangement for leap years. What's actually different? It would be best if this could be clearly summarised in the introduction to the article. (Huey45 (talk) 14:01, 2 July 2010 (UTC))
- The only difference is that three leap days are omitted every 400 years in the Gregorian calendar. This is explained in the introduction to the Gregorian calendar article, which is the more appropriate place. This introduction does link to that article in the second paragraph. --Chris Bennett (talk) 14:13, 2 July 2010 (UTC)
Fence post error?
IanOfNorwich suggests that the triennial leap year cycle described by Macrobius is an example of a fence post error. I haven't come across the term before, but I don't think this is correct, given the description pointed to. In essence, the distance between the fence posts was misunderstood, not the number of fence posts or the number of intervals between them.
What is an example of a fence post error, as described, is the inference that people draw from Macrobius' statement that the triennial cycle lasted for 36 years. Scaliger inferred 12 leap years from this, but Mommsen inferred 13. One of these numbers is due to a fence post error.
Well, it probably depends on how you view it. As I understand it, initially, a leap year was held every 3 years rather than 4, as had been intended and that this was due to a misunderstanding between the number of years between leap years (3) and the period of leap years (4). In which case by analogy 3 is the number of fence panels and 4 the number of fence posts.
The example you cite is indeed a good example of a fence post error (and Mommsen's inference almost certainly the correct one). I see how you could choose to exclude from the definition of a fence post error situations where the panel width is 1 but I see no reason to do so. In any case it's certainly not content essential to the article, but I thought an interesting link between normally unconnected topics. IanOfNorwich (talk) 17:34, 5 October 2010 (UTC)
Is it possible to simplify the text?
This has to be one of the most difficult articles I've read on Wikipedia. Is there any way to simplify it through a summary? Or a series of short summaries, one in each section? The contributors evidently know a great deal about this subject but like the poster above, I have read this article a couple times and having only a passing interest in the topic, my curiosity is not satisfied as there is too much detail to read through.
I would suggest that this article is uninviting to the average Wikipedia user and that it would benefit from a structural edit to make it more approachable.
For example, starting with a simple comparison of the Julian calendar and the Gregorian calendar most (English-speaking) users will be familiar with would help to set the scene. Then some history about its development and use would give the historical context. Finally, the bulk of the article could address the detail of the Julian calendar. Casual viewers would then have a quick high-level view of the topic, while those in need of detail can still obtain what they seek. Nick in syd (talk) 22:22, 15 October 2010 (UTC)
- I still feel it could do with simplifying. Some of the sentences have many sub-clauses, and would be more approachable if they were split into discrete sentences. For example:
- The Julian calendar was introduced by Julius Caesar in 46 BC as a reform of the Roman calendar. It came into force in 45 BC (709 ab urbe condita). It was chosen after consultation with the astronomer Sosigenes of Alexandria and was probably designed to approximate the tropical year (known at least since Hipparchus).
- The Julian calendar has a regular year of 365 days divided into 12 months with a leap day added to February every four years. The Julian year is, therefore, on average 365.25 days long.
- The more modern Gregorian calendar eventually superseded the Julian calendar: a tropical year (or solar year), which determines the cycle of seasons, is actually about 11 minutes shorter than 365.25 days. These extra 11 minutes per year in the Julian calendar caused it to gain about three days every four centuries when compared to the observed equinox times and the seasons. In the Gregorian calendar system, first proposed in the 16th century, this problem was dealt with by dropping some calendar days in order to realign the calendar and the equinox times. Consequently, the Gregorian calendar drops three leap year days across every four centuries. See Gregorian calendar for the details of how this is now done.
- Does this example show what I mean? Nick in syd (talk) 09:42, 22 October 2010 (UTC)
- Suits me. I've just used your text for the first part of the lede, with links added. I left the last two paragraphs in, since if the reader is satisfied at the end of your lede, he/she can just stop. And the present lede is not too long. So there we are. Go out and work on more ledes: you're an excellent minimalist writer, and this project doesn't have enough people like you. SBHarris 22:26, 25 November 2010 (UTC)
Error in Dating
The article seems to make the claim that Julius Caesar introduced the Julian calendar one year before it was put into force. The Gregorian calendar article says that the Julian calendar was introduced and put into force in the same year. Could somebody correct this (as the article is locked)? —Preceding unsigned comment added by 184.108.40.206 (talk) 03:30, 26 December 2010 (UTC)
- I can't find the bit in the Gregorian calendar article that you're referring to. Could you be more specific? SBHarris 04:30, 26 December 2010 (UTC)
- It was in Gregorian calendar#Beginning of the year. I removed "introduced" from both articles as imprecise and misleading, and replaced it with "began in 45 BC", although even that is somewhat misleading because the quadrennial Julian calendar did not begin until AD 4 or 8 after 45 years or so of erroneous leap years. — Joe Kress (talk) 09:56, 26 December 2010 (UTC)
- To me, it referred to Caesar's decree which "introduced" the reform in 46, and the use of the word was incorrect in the Gregorian calendar article. And actually the first step in the reform -- the two extraordinary intercalary months between November and December which realigned the year -- did take place in 46. Not a big deal -- it's only the lede, and the calendar itself did not begin operating till 45 (even if it was operated incorrectly at first). --Chris Bennett (talk) 19:37, 26 December 2010 (UTC)
Edits by Xact
- The phrase "during reign of Pope Gregory XIII" was added; if this is relevant, it would be better to state that Gregory XIII ordered the use of the calendar by those subject to him, rather than just say it was proposed during his regn.
- "The Holy See of the Roman Catholic Church, which holds the key to the calendar" is debatable. If some other calendar were adopted by most of the civil authorities, it is not at all clear the Holy See could maintain the use of the Gregorian calendar. Conversely, if the Holy See were to make a unilateral change to the calendar, it is highly unlikely the new version would attain the level of acceptance that the Gregorian calendar has. Jc3s5h (talk) 23:07, 6 February 2011 (UTC)
In need of Rewrite
This article is incomprehensible enough to deserve a reconsideration of how it's structured.
By way of my reading level, I'm degreed in Physics, studied plenty of history, worked as an engineer. I can't find the meat of the subject in this article.
Without delving too deeply, it seems the problem is in not explaining how the Julian calendar actually worked (which is what I wanted to know). History overwhelms the article and yet the history is not followable without a prior understanding of the main points of how the calendar works.
Edit request from Damienpryan1, 19 August 2011
|This edit request has been answered. Set the
"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."
Technically speaking the abvoe isn't true as later on Augustus Caesar took a day from Feburary and added it to Augustus. Also Augustus wouldn't have been knonw by that name yet.
- Not done: please be more specific about what needs to be changed. Topher385 (talk) 09:58, 19 August 2011 (UTC)
- I think he's complaining about the "setting the lengths of the months to the values they still hold today.", when the short length of February hasn't (obviously) been explained by the previous parts of the sentence. However, February has always had 28 days since long before Julius, and Octavian had nothing to do with that. So this needs to be noted (see the Julian calendar#Debunked theory on month lengths in this very article). Yes, the month Sextilis wasn't named Augustus (after Augustus) until 8 B.C., but Augustus didn't change its length, which had been 31 days since Julius Caesar and stayed that length. I've added a "see below" bit to the above sentence, but we could also move the "length myth debunk" section to just after this one, if it seems that more readers will have the same problem as the one above. SBHarris 22:18, 19 August 2011 (UTC)
- I'm not objecting to this but it does seem to me that the before and after 45 BC columns of the "Table of Months" immediately after the introduction illustrate the point rather clearly. Maybe this description should be moved from its currently location to immediately before or after the table, since it is the core of the reform? --Chris Bennett (talk) 01:41, 20 August 2011 (UTC)
Edit request on 21 December 2011
|This edit request has been answered. Set the
I want to add an external link to a menu page that is located at my home page. The links of the menu page are linking to web pages with weekday calculations in the Julian Calendar.
URL to my menu page: http://www.g-holbeck.com/english/tid/veckodagar
Link label: Calculation of weekday in the Julian Calender
Sources: Swedish book with title "Almanacka foer 500 aar" by Karl-Gustav Segland. Released in year 1984. Eilert Backman's Website, URL = http://web.comhem.se/~u12597836/index.htm
- There are at least three problems with this request:
- (1) The objections that Qwyrxian raised when you tried to add the same link to Week in November 2010 still apply, and they are equally valid here and in 45 BC.
- (2) The description of years in your second Julian table is wrong. 45 BC is not the same year as -45. See Astronomical year numbering. If your calculator is based on this assumption the results cannot be correct for BC years.
- (3) This table assumes that one particular model of the triennial leap year cycle is correct, but there are others in the literature. See the discussion in this article in the section Leap year error
- For these reasons I am also reverting the link you added to the same pages in 45 BC. --Chris Bennett (talk) 23:03, 21 December 2011 (UTC)
Edit request for "Motivation"
|This edit request has been answered. Set the
The last sentence references Pliny the Elder when claiming that the equinoxes and solstices were set to viii kal. of their respective months. However, the cited text of The Natural History only gives a calendar date for the winter solstice, December 25. Rather, extrapolating from the number of days he claims pass between these events, the summer solstice and autumnal equinox would instead be (roughly) June 27 and September 28, respectively. The March 25 date for the vernal equinox would be the same, but is not mentioned explicitly.
With that being said, Samuel Butcher's The Ecclesiastical Calendar (available through Google Books) also gives the viii kal. dates on page 16, but it is unclear where the author gets this information. (The book's primary source is the writings of Clavius, but I can't read Latin to verify.) — Preceding unsigned comment added by 220.127.116.11 (talk) 15:31, 22 December 2011 (UTC)
Done --Chris Bennett (talk) 21:10, 22 December 2011 (UTC)
Sacrobosco's theory on month lengths
As for me, it is necessary to add more references to the section "Sacrobosco's theory on month lengths". Now only two articles refuting the theory are cited: the first one is very old (of 1919), and the second one refutes the theory only because 31 August is present in one place of one table. For many people it is natural to think that these two articles may contain mistakes, since the Sacrobosco's theory is really very widespread and appears in some very reliable sources (for example, the Great Soviet Encyclopaedia). And as for now I am also not sure that this information from Wikipedia is true. --D.M. from Ukraine (talk) 22:39, 24 March 2012 (UTC)
- The article lists plenty of evidence -- the descriptions of the Julian reform by Macrobius and Censorinus, the internal structures of several months, a surviving pre-Julian calendar, and three contemporary documents from the period 45-8 BC which conflict with Sacrobosco's theory of how the calendar operated in those years. Are you asking for source citations for each of these items? Or is it not clear that they disprove Sacrobosco's theory? Your comment seems to imply that you think this evidence is of no value, yet surely a date of 31 August at a time when August supposedly had only 30 days, or a February with only 28 days at a time it supposedly had 29, are pretty clear indications of a problem? --Chris Bennett (talk) 05:11, 25 March 2012 (UTC)
- I'd like to see more sources in the section. Unfortunately, I cannot spend a lot of time to analyze this question. Maybe, there are many proper citations refuting the theory in other sections (other than "Sacrobosco's theory on month lengths"). Then, as for me, it would be better to cite some sources once again in the section "Sacrobosco's theory on month lengths" or to write something like "according to the information given in the section...". --D.M. from Ukraine (talk) 16:23, 25 March 2012 (UTC)
- I've added explicit source citations for each of the items of evidence listed in the article. Is that what you are looking for? Unfortunately, except for Censorinus, the citations that were not already there are only publicly available on the web in Latin (though the relevant pieces of Macrobius and Censorinus are translated in Lamont's article), and Degrassi's publication and discussion of the Fasti Caeretani, which is also in Latin, is not available on the web.
- I've also repositioned the citation to Lamont's 1919 article slightly to make it clear that the unique value of this article is that it traces the theory back to Sacrobosco, although his arguments against it are all perfectly valid. According to Pederson's 1985 survey of Sacrobosco's work there is no modern edition of his De anni ratione, and I haven't found one published since 1985, so Lamont is probably as good as we can get. Personally, I suspect that Sacrobosco didn't make this up, at least not entirely, but got it from some Greek source, directly or indirectly, since the pre-Julian calendar he describes is an ordinary Greek lunar calendar, but I can't prove it. --Chris Bennett (talk) 22:46, 25 March 2012 (UTC)
Hostility to southern hemisphere residents
Mr. Bennett's reversion of HTML2011's introduction of neutral language concerning the equinoxes indicate a lack of consideration for the mental gymnastics residents of the southern hemisphere must go through while reading articles like this. These readers may not have grown up in a culture where the connection Julian - Julius Caesar - Rome - northern hemisphere is second nature. Further, while trying to mentally picture the relationship of solar system objects, having to remember the article is using the opposite seasonal terminology than what is natural for the reader adds one more challenge to a task that is undoubtedly difficult for some readers. Finally, this article will not be of interest only to astronomers, so any association that astronomers might have between "vernal equinox" and "northward equinox" is not applicable to the readership of this article. Jc3s5h (talk) 17:30, 8 April 2012 (UTC)
- As one who was actually educated in the southern hemisphere I could find it very easy to resent your insinuation that education in that part of the world is so defective as not to cover the elementary fact that the seasons in the two hemispheres are of opposite polarity. It was drummed into us every Christmas! My own experience is entirely the opposite: once, having explained that I grew up in Australia I was, in all seriousness, asked by an American how I dealt with the heat, which must be extreme because Australia is so far south of the equator.
- Your argument that the terms "northward" and "southward" should be used so as not to confuse or belittle WP's poor benighted southern hemisphere readers is the same kind of political correctness one reads too much of in BC/AD vs BCE/CE debates. This argument distracts mightily from the real issue at hand: how does the choice of terminology clarify the text under review? Context is all important. I don't doubt that in certain technical astronomical contexts it is appropriate to use the "northward"/"southward" terminology to avoid ambiguity. But it is not in this context.
- The terms used should be both familiar and appropriate. "Vernal equinox" and "winter solstice" are certainly more familiar in ordinary English usage than "northward equinox" and "southward solstice". The context is a historical one, not an astronomical one. The terms are appropriate for that context. Vernal equinox is correct because it is associated with the Annunciation. Winter solstice is appropriate because the Anglo-Saxons celebrated the fact that the midpoint of winter had been reached and the days would now become longer.
- I also point out that the "vernal equinox" reference was already linked to an article on the equinox which explained the technical astronomical details, so the reader of this article who really did not understand what is meant could easily find out. The mention of the "winter solstice" was not so linked, but it would be very reasonable to add such a link. These links are all that is needed for the purposes of this article.
- I hope that you will accept that this minor emendation is all that this article needs to resolve this question.
- I am not too concerned with Australian readers, due to their cultural links to Europe, which will probably make the meaning apparent. I am more concerned with southern hemisphere readers with little cultural association with Europe, such as some countries in Africa. "Northward equinox" is not very familiar, so I would go along with the terms "March equinox" and "December solstice". Jc3s5h (talk) 14:41, 9 April 2012 (UTC)
- Looking into the history of this it appears that the mention of the vernal equinox was added by Piledhigheranddeeper about a year ago. While I think it's harmless, it doesn't actually add anything to the explanation of why 25 March was a New Year's Day -- the reason was that that was believed to be the date of the Incarnation, not that it was an approximation to the vernal equinox. I am perfectly happy to return to the previous text: However, most of those countries began their numbered year on 25 December (the Nativity of Jesus), 25 March (the Incarnation of Jesus), or even Easter, as in France.
- I added the statement about the winter solstice recently as part of a brief outline of the changes in New Year in England. In this case it is an essential part of the explanation of why 25 December was a common New Year's Day in Anglo-Saxon England: it was a near-direct transference of the pagan New Year, which was marked by the winter solstice. Since the seasonal association is the point, I cannot agree to replace "winter" by "December", because that obscures the point. ("Southward" is even worse, not just because it is arcane, but because it is a convention that makes the reference point the summer solstice of whatever hemisphere is identified by the direction.) Moreover, explaining that 25 December was the "December" solstice is bad style -- it looks tautologous.
- Some stats for you. This table gives the number of articles in the NASA/Harvard Astrophysics database using various terms describing equinoxes and solstices. (Their search engine treats terms of the form <term>[<variant>] as equivalent.)
|Term||Number of articles|
- Clearly the dominant convention used by professional astronomers is seasonal. Month-based terminology is about half as common, and "northward"/"southward" isn't even in the running. I don't see why WP should be different.
- So: second proposal: (a) strike the mention of "vernal equinox" and (b) wikify the mention of "winter solstice". --Chris Bennett (talk) 19:12, 9 April 2012 (UTC)
- I agree that the equinox seems irrelevant to the start of annunciation-style start of year, and could be stricken.
- The first mention of the winter solstice is in the phrase "when Pliny dated the winter solstice to 25 December" and is acceptable since "December" and "solstice" are in close proximity, and that mention of solstice could be wikified.
- Later, in the phrase "In Anglo-Saxon England, the year most commonly began on 25 December, which, as the Southern solstice" I could go along with "winter solstice" since the sentence makes it clear that both the northern hemisphere and December are intended.
- In general, I wouldn't put too much weight on astronomical usage in an article aimed at a more general audience. Sure, don't contradict astronomical usage, but astronomers deal with a frightful array of reference systems, and seem accustomed to twisting and turning from one system to another in ways that will leave a normal person dizzy. So when used in isolation, I would still prefer month-based names to season-based names. Jc3s5h (talk) 19:53, 9 April 2012 (UTC)
- I read this as agreement to (1) "vernal equinox" being struck (2) "Southern solstice" => "winter solstice", as before, and have implemented it. Additionally (3) I have wikified "winter solstice" on both mentions, since they are quite widely separated and the second was already wikified when "southern" was introduced. -- Chris Bennett (talk) 20:14, 9 April 2012 (UTC)
Edit request on 26 April 2012
|This edit request has been answered. Set the
I notice "have also replaced it by the Gregorian calendar".
Usually, I'd see "with" instead of "by"; please consider making that change here.
Edit request on 26 April 2012
|This edit request has been answered. Set the
"Since 2000 was a leap year according to the Gregorian calendar, the Julian calendar remained in step with it:"
I suggest some rewording; try this: "Since 2000 was a leap year according to both the Julian and the Gregorian calendars, the difference of 13 stayed the same:"
The idea is to remove "remained in step with it" because the Julian calendar is 13 days OUT OF STEP with the Gregorian (until during the year 2100, when the difference increases to 14 days).
Edit request on 27 April 2012
|This edit request has been answered. Set the
In reference to the current 13-day difference between Julian & Gregorian calendars, I find:
"This difference will persist through the last day of February, 2100 (Julian),"
Try "Gregorian" in place of "JuliAan" in parentheses in the string I just quoted. Notice that the calendar would have:
15 Feb. 2100 (Julian) is 28 FebA. 2100 (Gregorian) -- 13 day difference
16 Feb. 2100 (Julian) is 1 March 2100 (Gregorian) -- 14 day difference because the Julian calendar will have to include Feb. 29 and the Gregorian calendar will have just skipped it.
- I agree that this change is necessary. However, two parts of the paragraph are still problematic.
- The first is: "Thus, in the year 1700 the difference increased to 11 days after February 28 (Gregorian); in 1800, 12; and in 1900, 13." where "February 28 (Gregorian)" should be changed to "29 February (Julian)".
- The second is: "Monday 1 March 2100 (Gregorian) falls on Monday 16 February 2100 (Julian), a full two-week discrepancy." This should be changed to "Monday 1 March 2100 (Julian) falls on Monday 15 March 2100 (Gregorian), a full two-week discrepancy."
- Stating that the difference between the Julian and Gregorian calendars is a specific number of days implies that that difference is the same when going from Julian to Gregorian and from Gregorian to Julian. They should differ only in the sign of the number of days, in this case (after 1582), positive when going from Julian to Gregorian and negative when going from Gregorian to Julian. This is true as long as the number of days in corresponding months is the same in both calendars. But between 1 March (Gregorian) and 29 February (Julian), both inclusive, in 1700, 1800, 1900, 2100, etc., a no man's land exists where the absolute value of the difference differs by one day depending on the direction (Julian to Gregorian vs Gregorian to Julian) and whether February is assumed to have 28 or 29 days.
- These lines show the correspondence between Julian and Gregorian calendars in 2100:
G Feb 27 28 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Mar
J Feb 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 1 2 Mar
- The following two lines show the number of days counted naturally. That is, when going from Julian to Gregorian count toward the right (in the positive direction) on the Julian line with a February 29, but when going from Gregorian to Julian count toward the left (negative) on the Gregorian line without a February 29. In the latter case a February 29 (Julian) cannot be generated, here marked by X. Also note that in "no man's land" Julian to Gregorian is +14 days, but Gregorian to Julian is −13 days.
J>29>G +13 +13 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14 +14
G>28>J -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 -13 X -14 -14
- The following two lines show the number of days counted unnaturally. That is, Julian to Gregorian without February 29, but Gregorian to Julian with February 29. Julian to Gregorian now has X, whereas the conversion days still differ, now +13 vs −14.
J>28>G +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 +13 X +14 +14
G>29>J -13 -13 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14 -14
- The variations in "no man's land" are beyond the scope of this article and should not be discussed. My suggested corrections avoid that discussion. — Joe Kress (talk) 08:44, 28 April 2012 (UTC)
- Hmm. AFAIK the usual convention is to account the difference as increasing on the single day where the date of 29 February (G) is dropped, which is what the current text describes [though it would be clearer to say "on 1 March (G)" than "after 28 February (G)"]. I see that the discussions at Gregorian calendar#Difference between Gregorian and Julian calendar dates and Conversion between Julian and Gregorian calendars also account the difference as increasing on 1 March (G).
- Your convention arrives at two different days for the increase, depending which calendar you are considering. This seems counter-intuitive and confusing, especially since you also end up with an indeterminate difference between the two calendars. After all, the physical day X exists, and it has a real date in both calendars -- in your example February 29 (J) = 14 March (G). This suggests a definitional problem to me.
- Nautical Almanac Offices of the United Kingdom and the United States of America (1961) provide a table on 417. Although there is no blow-by-blow explanation of the difference column, one can infer that they always count off the days on a Gregorian calendar. The Gregorian date for Julian Feb. 29 in Gregorian common years is always listed explicitly, and the difference column for these dates is blank. I must say I find the other arguments in this section hard to follow, and would appreciate if Chris Bennett could supply a reliable source for "the usual convention". In view of Chris' interest in calendar matters, he might find the 1961 source a worthwhile purchase; it seems to be widely cited on the subject of Gregorian-Julian conversions, as well as listing dates when countries converted to the Gregorian calendar. Jc3s5h (talk) 18:18, 30 April 2012 (UTC).
- OK, thanks for the citation. I don't have easy access to this and since my interest stems from an interest in ancient chronology, which standardises on the Julian calendar, I rarely have actual occasion to perform Gregorian/Julian conversions. That being said, I assume from your description that the table you refer to is similar to the one you have generated in Talk:Conversion between Julian and Gregorian calendars#Need to review these conversions?? If I saw this table without your interpretive discussion, I would not think it showed that the difference between the two calendars depends on which direction you are going. Rather I would think it was illustrating that the effect of dropping the date of February 29 in the Gregorian calendar causes the difference between it and the Julian calendar to increase by a day from that point forward. Joe's discussion above illustrates the theory you both describe more clearly and explicitly.
- What I described as "the usual convention" = the way I have always understood it, not much different from my understanding that 2+2=4, so perhaps a little hyperbolic (I did say "AFAIK"). I don't understand your comment that it is "hard to follow". It seems to me obvious and natural that the relationship between the calendars would change at the point where the Gregorian calendar omits a February 29 that exists only in the Julian calendar, and only at that point, since that is the sole difference in calendar structure. To me, the convention you and Joe are describing is much harder to understand: it is asymmetrical, it creates two transition points not one, and the second has an undefined state that has no obvious necessity or value. But that's just my opinion.
- On reliable sources: Since "there is no blow-by-blow explanation of the difference column", the Almanac is not explicit enough to qualify as a reliable source for the asymmetric convention. Such a source would need to be something authoritative that actually works through all the complexities that Joe describes above, or close to it. I don't have a source for the symmetric convention to hand -- until this discussion I was not aware that anyone thought of it any other way, or even that they could, and a quick pass through my own library isn't helpful. For either convention, the source should be a book on calendars that works through the transition point in detail. I suggested Blackburn & Holford-Strevens as one possibility, perhaps there are others.
- This article is not the main discussion of the relationship between the two calendars. It's possible to read the current text in a way that is consistent with either convention, now that you have eliminated the "full two-week discrepancy" comment. Hopefully we can keep this article out of the debate on that basis.
- The places where the convention really needs to be settled are the Gregorian calendar#Difference between Gregorian and Julian calendar dates and Conversion between Julian and Gregorian calendars discussions, both of which purport to go into detail. I see you and the IP editor are starting to revert each other's table in the Gregorian calendar#Difference between Gregorian and Julian calendar dates discussion. I suggest you hold off until a good RS is found. I also note that that table is only showing a single value for the difference, and that your version is standardising on Julian 29 February as a sole transition point, with no mention of either Gregorian 1 March or asymmetric differences. That does not accurately reflect the convention being proposed. Also those two discussions should use the same convention. They currently do not. --Chris Bennett (talk) 02:38, 1 May 2012 (UTC)
- Chris Bennett asked if Conversion between Julian and Gregorian calendars agrees with the 1961 explanatory supplement. Yes, I input it, and made it agree as closely as I could considering that Wikipedia does not support some of the odd typography used in that source.
- As for an asymmetric algorithm, I didn't really follow Joe Kress' comments about that; I see nothing asymmetric about the method for using the table in the 1961 explanatory supplement.
- The way I look at it, a date like "1 May 2012" is more like a name than a number, because dates advance in an irregular way that does not easily accommodate arithmetic. So the Julian and Gregorian calendars are essentially lists of names, not unlike the lists of Roman consuls who used to be used to name years. There are two different lists, because some of the February 29ths on the Julian list have been omitted from the Gregorian list. There are periods lasting about a century or two where the two lists are the same, but offset. For example, the lists are the same from 1 March 1700 to 28 February 1800. So during these periods you can find the offset (11 days for our example) and count forward or back on the list to do calendar conversions (but all bets are off if you go off the end of the list).
- If you want to come up with an algorithm that describes a date conversion where you would have to count past a 29 February on one list, but not the other, a thorough description of the algorithm should be provided and any offset that might be provided in a table must be calculated to harmonize with the algorithm. Jc3s5h (talk) 03:29, 1 May 2012 (UTC)
- Perhaps I misunderstood your editorial comment "Could be 13 days or 14 days depending on whether you count off the days on a Gregorian or Julian calendar". This appeared to be exactly the asymmetry Joe described. I understand his theory, but I seriously doubt that that is how the relationship between the two calendars from 1 March (G) to 29 February (J) is normally accounted in centennial years ≠ 0 (mod 400), and would like to see evidence of it before it gets incorporated into WP, in this article or any other.
- I agree that anyone who wants to come up with a bidirectional computational algorithm (in the appropriate place) needs to describe it very carefully. FWIW I think the latest changes to the table in Conversion between Julian and Gregorian calendars has made things worse, not better. But I would really prefer to keep out of this! --Chris Bennett (talk) 17:48, 1 May 2012 (UTC)
- I certainly have not though of every possible algorithm that lists a difference for every date range in the calendars, and has an algorithm that can convert any date. I don't know if such an algorithm must be asymmetric. The only thing I'm sure of is the calendar you count the days off on can't be the Gregorian calendar, because there would be no way to convert from, for example, March 13, 1900, Gregorian to February 29, 1900 Julian. I'm willing to consider this thread closed. Jc3s5h (talk) 18:55, 1 May 2012 (UTC)
Edit Request on 6 October 2012
Ewawer rewrote and reordered the introductory paragraphs a few days ago. He has a fair point that the introduction should say briefly where and how the Julian calendar was mainly used after it was introduced, but its use was not limited to Europe. Also, the rewrites are rather clumsy, and the reordering makes it seem as though it is more important to understand how the calendar is used by the Orthodox church than it is to understand the actual structure of the calendar, which doesn't seem right to me.
Since the article is permanently semi-protected, could someone look at this and do some editorial cleanup? I prefer the previous version. I think it only needs some minor tweaking to the first paragraph of that version to fix what seems to be the main point of Ewawer's change; perhaps that paragraph should be split into two. Something like:
- The Julian calendar is a reform of the Roman calendar introduced by Julius Caesar in 46 BC (708 AUC). It took effect the following year, 45 BC (709 AUC), and was the principal civil calendar in Europe and in European colonies until it was replaced by the Gregorian calendar. It continued to be used
as the civil calendarin some countries into the 20th century.
- The calendar has a regular year of 365 days divided into 12 months, as listed in Table of months. A leap day is added to February every four years. The Julian year is, therefore, on average 365.25 days long.
Month name questions & new year
I have a question. If 1 January was the first day of the year most of the past two millenia, why are the last 4 months of the 12 month year named "7, 8, 9, & 10?" (Septem, octem, novem, decem)
Also, I was told once that 1 April was called "April fools" because the calendar had changed new years from 1 April to 1 January, so those wishing you "Happy New Year" on 1 April were called "April fools." Any merit in this?
- Blackburn and Holford-Strevens (see footnote 4 in the article for full details) on page 669 indicate that the legendary king Romulus is reputed to have created a ten month calendar, which would explain why, among the months named with Latin number-words, there are none higher than 10. But the historical records don't go back far enough to figure out the details. Jc3s5h (talk) 16:45, 7 November 2012 (UTC)
- January and February initially were not months in the Romulus Calendar, which included 51 days not counted and not named during the winter. The new year then started on March and was terminated on December (the 10th month of the calendar).
- New Year remained on March 1 even after the Numa calendar decided to shorten the 10 months, in order to create two full months in January and February, which were placed at the begining of the Calendar for one good reason: the last days of February (just before the important date of March 1) was a time for celebration or purification prior to this most important Kalends day. If January and February had been placed at end of the calendar, they would not be grouped with March 1 and would not match the Roman practice of counting of days backward to important dates (instead of foreward today.
- So the Roman calendar since Numa places January and February at the begining of the CALENDAR, but at end of the YEAR. The YEAR unambiguously started on March 1 (and this was the date where new years could be named after the name of an emperor or consul : these years were counted foreward since March 1 in their year of accession to power). Even the backward counting in Roman tradition obeys the same rule: calendars were used FIRST to prepare the FUTURE, not preserving the PAST (so the importance given to prediction in paganism, completely opposed to Christianity desire to keep track of the past and notably for the birth of Jesus, meaning that backward counting on calendars was abolished at the same time as Christianity became the single rule in the old Roman Empire).
- So effectively, January was the 11th month of the Roman year, and February the 12th, even if they appeared at start of the calendar since Numa and were not named in the Romulus calendar which still placed "Winter" at the begining of the calendar, only to prepare the FUTURE fests of March). In Christianity ONLY God knows the FUTURE. Christian humans have to keep track the PAST and must not resist to what will happen in the FUTURE (religious fests may be delayed, but must not occur in advance, so the Christian Easter is celebrated LATE, after the effective equinox).
- The New Year shifted from March 1 to January 1 very late (many centuries after the adoption of the Julian calendar or even the Gregorian calendar), causing a change in how months were assigned to numbered years (before this occured, it was needed to define the epoch after the birth of Jesus, and this only happened in the Concile of Nicee during the 3rd century, when the Roman empire was converted to christinity and counting years from past rulers was abolished in favor of a single epoch, and when January was judged preferable to align the calendar and the year, or to align the christian festivities related to Jesus birth, Christmas and Epiphany, to the new Year in January, instead of the old paganist fests of the Kalends of March).
- Note that Christian rulers decided to use the events related to Jesus christ birth in preference to the other celebrations of Spring (i.e. Easter). In some orthodox christian calendars the New Year is still celebrated on Easter or near the spring equinox on 21 March, even if their calendars are now counting January as their 1st month on their calendar (this means that their months in the same year are number in this order: 11,12,1,2,3,4,5,6,7,8,9,10, to match the month names !)
- Some of these local orthodox calendars have abolished the old Paganist month names (January, February, March, April, May, June, named after Roman gods or godesses) and the names related to Roman emperors ("Julius"=July, "Augustus"=August) to use only names based on these month numbers (something similar to "Undecilis"/"Undecember"=January, "Duodecilis"/"Duodecember"=February, "Unilis"/"Unember"=March, "Duilis"/"Duember"=April, "Trilis"/"Triember"=May, "Quadrilis"/"Quadriember"=June, "Quintilis"/"Quintember"=July, "Sextilis"/"Sextember"=August), but this never succeeded, so the Roman Paganist and two Emperial names have survived.
- (The Roman Catholic church in fact did not want to abolish the reference to the old Roman Empire, where Christianity was born, and that caused Christianity to spread throughout the Empire and the world, and survive up to today ; in fact many Christian events are related now to old Paganist fests, including Easter; the old Paganist gods and goddesses are forgotten and were no longer a threat to the Christinity of the Empire, but was a proof given to other countries with religions that they should also convert to Christinity and have some recognition of their festive traditions, compatible with Christinity ; so even today, God is named "Allah" for Christians speaking Arabic, or "Yeovah"/"Yaveh" for Christians speaking Hebrew).
- Month names are not judged important in Christianity, only numbers on calendars have some spituality assigned to them (they are immutable and must occur in a fixed sequence without any hole or repetition – unlike the Jewish and Islamic calendars where some months may be repeated and have names more important than their numbers, even if Hebrews have kept some numerologic traditions from old paganist times, but only in their alphabet and not in their sacred calendar).
- verdy_p (talk) 16:17, 14 December 2012 (UTC)
What was the Julian calendar aligned to?
On the section Realignment of the year it is stated that: “The first step of the reform was to realign the start of the calendar year (1 January) to the tropical year”, but it is not clear to me what were they trying to align the calendar to? After the "calendar alignment" important astronomical events such as the winter solstice or spring equinox would fall on December 25 and March 25 respectively. Why would the romans want to align their calendar to these (seemingly) arbitrary dates? I've also asked a question regarding this issue at History StackExchange site. -- NavarroJ (talk) 12:58, 3 January 2013 (UTC)
- The short answer is that no one knows whether Caesar intended to align the calendar to a specific astronomical event, or just intended the months to be aligned to the seasons. I have expanded the footnote on this point. As noted, Ideler thought 25 December was a "traditional" date for the winter solstice, but the evidence for this date is all post-Julian -- and in fact Varro, in 37 BC, does not give this date. So it is perfectly likely that the date of the winter solstice was fixed at 25 December after the Julian reform, and as a side-effect of it. --Chris Bennett (talk) 03:20, 24 February 2013 (UTC)
Error in comparison of Julian and Gregorian dates in the lead text
The article states correctly that the Julian calender gains about three days every four centuries but later incorrectly states " Consequently, the Julian calendar is currently 13 days behind the Gregorian calendar; for instance, 1 January in the Julian calendar is 14 January in the Gregorian" which should be opposite " Consequently, the Julian calendar is currently 13 days
behind advanced the Gregorian calendar; for instance, 1 13 January in the Julian calendar is 14 1 January in the Gregorian"
- I agree this section is confusing, but I suggest a different approach, involving a more complete rewrite. Since Julian and Gregorian calendars are not a count of days like Julian dates, it may be more useful to think of Julian and Gregorian calendars as naming days, rather than numbering days. Words like "gain" or "difference" are confusing in contexts where arithmetic can't be done on these dates directly. So maybe we should concentrate on how the seasonal phenomena move through the calendar dates.
- Consider "As a result, the calendar year gained about three days every four centuries compared to observed equinox times and the seasons." This could be interpreted to mean that the calendar year was 365 days long in AD 1, but by AD 401 it had increased to 369 days, which of course is nonsense. Maybe something like As a result, the dates of equinoxes and seasons moved about three days earlier in the calendar year every four centuries.
- For "Consequently, the Julian calendar is currently 13 days behind the Gregorian calendar; for instance, 1 January in the Julian calendar is 14 January in the Gregorian" we might write Consequently, for the 21st, 22nd, 23rd, and 24th centuries, 14 January Gregorian is the same day as 1 January Julian.''Astronomical Almanac for the Year 2011''. Washington: US Government Printing Office. 2010. B4.
- If you use the fourmilab site to convert 1 January 2013 from Gregorian to Julian, you find that it is 19 December 2012, not 13 January 2013. Jc3s5h (talk) 14:06, 5 July 2013 (UTC)
- This seems unnecessarily detailed to me. The sentence is in the lead, which is supposed to be just a general introduction: "currently" is surely enough to signal that the exact relationship can and does change, and no more needs to be said. Also, the example given (which is, as you note, correct) should be enough to clarify any uncertainty about the meaning of "behind". So I have no problem with the sentence as it stands, I don't find it confusing at all.
- I do have a problem with the first (italicized) sentence, which describes the Julian calendar as "the calendar used in the late Roman Republic and the Roman Empire". While it is a true statement (though other calendars were also used), it is incomplete and strongly implies that the Julian calendar was not used after the fall of the Empire, which couldn't be more wrong. I'm not sure why it is necessary to distinguish the Julian calendar from the Julian Day at the very start of the article, instead of just including "Julian Day" in the "See also" section. I guess the point is about the use of the calendar (in which case "astronomical" is also incomplete). Anyway, accepting for the sake of argument that the distinction must be made here, perhaps this paragraph could be rewritten as:
- This is an article about the calendar used for civil and liturgical purposes. See Julian day for the day-number calendar used for astronomical and historical calculations.
though my preference would be to delete it entirely.
It is customary to a templates at the top of the article to direct readers to other articles that are likely to be what the reader really wanted to find. I agree that the current wording implies the Julian calendar fell out of use much earlier than it actually did. But ...BDF8's proposed wording would suggest it is the primary calender in current use, but in fact, the Gregorian calendar is the world's primary calendar today. I can't think of brief wording that would describe the real status of the Julian calendar. Jc3s5h (talk) 19:41, 14 September 2013 (UTC)
- I agree that the need for the redirect is based on someone's assessment that the alternative is "likely to be what the reader really wanted to find". I don't know what basis s/he had for that assessment. IMO it will only be true for a very small number of readers. But my statistics are no better than yours -- i.e. bias and guesswork -- so I don't object to leaving it in, I just don't see any evidence that it is actually justified.
- As to alternate wording, how about:
- This is an article about a calendar formerly widely used for civil and liturgical purposes. See Julian day for the day-number calendar sometimes used for astronomical and historical calculations.
- though this might offend some Berbers and some of the Orthodox who still use it. Or even:
- This is an article about a calendar used for civil and liturgical purposes. See Julian day for the day-number calendar used for astronomical and historical calculations.
- Meaning that this is just one civil and liturgical calendar among many, with no implications at all of current status, which was my original intent. 2602:304:7882:B1C9:24BE:AC33:435F:26C2 (talk) 20:23, 14 September 2013 (UTC)
- So does that mean you are comfortable with my second suggestion? Since the article is semi-protected, and I have no interest in setting up a WP user account after previous experiences, could I ask you to make the edit? Thanks. 2602:304:7882:B1C9:24BE:AC33:435F:26C2 (talk) 22:13, 14 September 2013 (UTC)
Edit request on 16 September 2013
|This edit request has been answered. Set the
For reasons discussed in the previous section concerning misleading historical implications, please change the initial paragraph, which currently reads:
- This is an article on the calendar used in the late Roman Republic and Roman Empire, see Julian day for the day-number calendar used for astronomical calculations.
- I'm not seeing a consensus for a specific wording in the previous section. It might be better to get more user input on this. I've unprotected the page as the previous protection was for a specific incident in 2010. This mean you should be able to edit the page yourself.--User:Salix alba (talk): 11:28, 18 September 2013 (UTC)
- Thanks. As for getting more user input there doesn't seem to be much interest. We do have agreement that the current wording is misleading, we have an objection to one proposed alternative, and no response to another made in the same breath, which indicates, at a minimum, lack of objection to me. I think that's sufficient grounds to make the edit. If someone decides at this point to object to it they can do so. 2602:304:7882:3479:3120:F0E5:675A:CBC8 (talk) 17:33, 18 September 2013 (UTC)
First Aligned Day must be wrong
The article lists a host of "First Aligned Day" for various theories of the leap years before AD.
These first aligned days almost certainly HAVE to be wrong. The only way that the calendars get misaligned or aligned is by adding and subtracting the 29th of February. Hence there can be NO SUDDEN ALIGNMENT before that date.
In fact, I have looked over Bennett's data and his first alignment is 1 March BC 1.
- Only in modern times was the leap day considered to be February 29. Originally what we would call February 24 was the leap day. According to Richards (cited as source 4 in the article) on page 595, section 15.3.3, "Caesar's Reform",
This intercalary day was inserted before VI Kal. Mar. and termed Bis VI Kal. Mar.; it fell between VII Kal. Mar. (February 23) and VI Kal. Mar. (February 25th). [Internal cross-references omitted.]
- I suspect if you check the modern observances of saint's days in the Roman Catholic Church, comparing a common year to a bissextile year, you will see that the observances are arranged as if February 24 is the leap day. Jc3s5h (talk) 03:16, 21 April 2014 (UTC)
RFC: Is the Julian a reform of Egyptian calendar?
|requested comments from other editors for this discussion. This page has been added to the following lists:An editor has|
It's Roman. The Julian calendar resembles the old Roman one far more than the Egyptian one. The Julian and old Roman calendars both have months of varying length, versus 12 30-day months in the Egyptian calendar. Also, the Julian calendar had the same month names as the old calendar; even Julius Caesar wasn't bold enough to name a month after himself. In the absence of any compelling evidence to the contrary I think the edit should remain reverted. Roches (talk) 00:09, 2 October 2014 (UTC)
- I agree that it is Roman and not Egyptian. The naming of the individual days (relative to the nones, ides and kalendae) in the Julian calendar is clearly based on the similar system already employed in the Republican calendar. The edits by User:Rarevogel should be reverted. AstroLynx (talk) 08:19, 2 October 2014 (UTC)
I'm the initiator of the RFC. I also think it is a reform of the Roman calendar, mainly because that is the first calendar that was displaced by the new one. I note that User:Arcorann has changed it to "Roman" in the article. I provided a source which supports the claim. The supporting text in Richards is
By −46, the Roman calendar had gone badly awry; the months no longer followed the lunations and the year had lost step with the cycle of the seasons. This state of affairs was reformed by Julius Caesar (107–44 B.C.), who took the advise of the Alexandrian astronomer Sosigenes. [Citations within Richards' text omitted.]
- Guys, I don't think this is really debateble.. You won't find any scholar anywhere who willclaim that the Julian calendar is derived from the Old Roman Calendar. The Julian calendar REPLACED the Old Roman one, but is not derived from it.— Preceding unsigned comment added by Rarevogel (talk • contribs) 09:34, 3 October 2014 (UTC)
- If you're saying the astronomical underpinnings of the Julian calendar are based on the Egyptian calendar, and on Egyptian astronomical knowledge, that's undisputed. But the language used to describe dates was not significantly changed when the Julian calendar replaced the Roman calendar. When the Gregorian calendar replaced the Julian calendar, it took advantage of ideas and observations that were unknown in the first century BC, such as the ideas of Copernicus, yet we say the Gregorian calendar was a reform of the Julian calendar. Jc3s5h (talk) 13:34, 3 October 2014 (UTC)
- ITS EGYPTIAN!!----The Egyptian calendar was later disseminated by the Ptolemies in parts of their eastern Mediterranean empire, possibly leading to the creation of the 364-day Judaean calendar. Finally, the Egyptian calendar was used as a model for the institution in Rome of the Julian calendar. In this context, attention is given to the Roman calendar that preceded it, and to the reasons why Julius Caesar instituted a new calendar. Weird right?? The herald 14:13, 12 October 2014 (UTC)
- Roman, but clarify. My brief research seems to indicate that it is usually referred to as a reform of the Roman calendar. If I understand things correctly, the Romans basically took the Egyptian solar calendar year and adopted it into their system. The article should probably say something to that effect, but the local editors probably know better than I do how to say it. Alsee (talk) 01:40, 19 October 2014 (UTC)