International Fixed Calendar

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The International Fixed Calendar (also known as the Cotsworth plan, the Cotsworth calendar, the Eastman plan or the Yearal) [1] was a proposed reform of the Gregorian calendar designed by Moses B. Cotsworth, first presented in 1902. [2] The International Fixed Calendar divides the year into 13 months of 28 days each. A type of perennial calendar, every date is fixed to the same weekday every year. Though it was never officially adopted at the country level, the entrepreneur George Eastman instituted its use at the Eastman Kodak Company in 1928, where it was used until 1989. [3] While it is sometimes described as the 13-month calendar or the equal-month calendar, various alternative calendar designs share these features.

Contents

Rules

The calendar year has 13 months with 28 days each, divided into exactly 4 weeks (13 × 28 = 364). An extra day added as a holiday at the end of the year (after December 28, i.e. equal to December 31 Gregorian), sometimes called "Year Day", does not belong to any week and brings the total to 365 days. Each year coincides with the corresponding Gregorian year, so January 1 in the Cotsworth calendar always falls on Gregorian January 1. [a] Twelve months are named and ordered the same as those of the Gregorian calendar, except that the extra month is inserted between June and July, and called Sol. Situated in mid-summer (from the point of view of its Northern Hemisphere authors) and including the mid-year solstice , the name of the new month was chosen in homage to the sun. [4]

Leap years in the International Fixed Calendar contain 366 days, and its occurrence follows the Gregorian rule. There is a leap year in every year whose number is divisible by 4, but not if the year number is divisible by 100, unless it is also divisible by 400. So although the year 2000 was a leap year, the years 1700, 1800, and 1900 were common years. The International Fixed Calendar inserts the extra day in leap years as June 29 - between Saturday June 28 and Sunday Sol 1.

Each month begins on a Sunday, and ends on a Saturday; consequently, every year begins on Sunday. Neither Year Day nor Leap Day are considered to be part of any week; they are preceded by a Saturday and are followed by a Sunday, making a long weekend. As a result, a particular day usually has a different day of the week in the IFC than in all traditional calendars that contain a seven-day week. The IFC is, however, almost compatible with the World Calendar in this regard, because it also starts Sunday and has the extra day at the end of the year and the leap day in the middle, except IFC leaps on Gregorian June 17 and TWC leaps two weeks later on July 1. Since this break of the ancient week cycle has been a major concern raised against its adoption, various leap week calendars have been proposed as a solution.

Common arrangement of all months
Days of the week
SunMonTueWedThuFriSatHol
01020304050607Leap Day,
Year Day
08091011121314
15161718192021
22232425262728X*

* The two special dates have been recorded as either the 29th day of the month ending or the 0th day of the month beginning, or, more correctly, as outside any month and week with no ordinal number.

The date for today, 9 November 2024, using this calendar is Thursday, 5 November 2024.

The following table shows how the 13 months and extra days of the International Fixed Calendar occur in relation to the dates of the Gregorian calendar:

IFCMatching dates on the Gregorian calendar
Starts on fixed day 1Ends on fixed day 28
JanuaryJanuary 1January 28
FebruaryJanuary 29February 25
MarchFebruary 26March 25*
AprilMarch 26*April 22*
MayApril 23*May 20*
JuneMay 21*June 17*
Leap Day*June 17
SolJune 18July 15
JulyJuly 16August 12
AugustAugust 13September 9
SeptemberSeptember 10October 7
OctoberOctober 8November 4
NovemberNovember 5December 2
DecemberDecember 3December 30
Year DayDecember 31

* In a leap year, these Gregorian dates between March and June are a day earlier. March in the Fixed Calendar always has a fixed number of days (28), and includes an eventual Gregorian February 29. The rule for finding leap years is the same in both calendars.

History

Lunisolar calendars, with fixed weekdays, existed in many ancient cultures, with certain holidays always falling on the same dates of the month and days of the week.

The idea of a 13-month perennial calendar has been around since at least the middle of the 18th century. Versions of the idea differ mainly on how the months are named, and the treatment of the extra day in leap year.

The "Georgian calendar" was proposed in 1745 by Reverend Hugh Jones, an American colonist from Maryland writing under the pen name Hirossa Ap-Iccim. [5] The author named the plan, and the thirteenth month, after King George II of Great Britain. The 365th day each year was to be set aside as Christmas. The treatment of leap year varied from the Gregorian rule, however, and the year would begin closer to the winter solstice. In a later version of the plan, published in 1753, the 13 months were all renamed for Christian saints.

In 1849 the French philosopher Auguste Comte (1798–1857) proposed the 13-month Positivist Calendar , naming the months: Moses, Homer, Aristotle, Archimedes, Caesar, St Paul, Charlemagne, Dante, Gutenberg, Shakespeare, Descartes, Frederic and Bichat. The days of the year were likewise dedicated to "saints" in the Positivist Religion of Humanity. Positivist weeks, months, and years begin with Monday instead of Sunday. Comte also reset the year number, beginning the era of his calendar (year 1) with the Gregorian year 1789. For the extra days of the year not belonging to any week or month, Comte followed the pattern of Ap-Iccim (Jones), ending each year with a festival on the 365th day, followed by a subsequent feast day occurring only in leap years.

Whether Moses Cotsworth was familiar with the 13-month plans that preceded his International Fixed Calendar is not known. He did follow Ap-Iccim (Jones) in designating the 365th day of the year as Christmas. His suggestion was that this last day of the year should be designated a Sunday, and hence, because the following day would be New Year's Day and a Sunday also, he called it a Double Sunday. [6] Since Cotsworth's goal was a simplified, more "rational" calendar for business and industry, he would carry over all the features of the Gregorian calendar consistent with this goal, including the traditional month names, the week beginning on Sunday (still traditionally used in US, but uncommon in Europe and in the ISO week standard, starting their weeks on Monday), and the Gregorian leap-year rule.

To promote Cotsworth's calendar reform the International Fixed Calendar League was founded in 1923, just after the plan was selected by the League of Nations as the best of 130 calendar proposals put forward. [7] Sir Sandford Fleming, the inventor and driving force behind worldwide adoption of standard time, became the first president of the IFCL. [8] The League opened offices in London and later in Rochester, New York. George Eastman, of the Eastman Kodak Company, became a fervent supporter of the IFC, and instituted its use at Kodak. Some organized opposition to the proposed reform came from rabbi Joseph Hertz, who objected to the way that the Jewish Sabbath would move throughout the week. [9] The International Fixed Calendar League ceased operations shortly after the calendar plan failed to win final approval of the League of Nations in 1937. [10]

See also

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References

Notes

  1. ↑ See the table in Cotsworth 1905, p. i

Citations

  1. ↑ Cook, Anna J, (2024) A Man Beyond Time: Moses Cotsworth's fight for the 13-month calendar Independent Publishing Network
  2. ↑ Cotsworth 1905.
  3. ↑ "Eastman Kodak going on our calendar". Associated Press. September 11, 1988. Retrieved July 24, 2024.
  4. ↑ Cotsworth suggested "Mid" as an alternative name. See his address in Royal Society of Canada, Proceedings and Transactions of the Royal Society of Canada, 3d series, vol. II (Ottawa: James Hope & Son, 1908), pp. 211-41 at 231.
  5. ↑ Hirossa Ap-Iccim, "An Essay on the British Computation of Time, Coins, Weights, and Measures" The Gentleman's Magazine, 15 (1745): 377-379
  6. ↑ Cotsworth 1905, p. i.
  7. ↑ Duncan Steel, Marking Time: The Epic Quest to Invent the Perfect Calendar (New York: John Wiley & Sons, 2000), page 309
  8. ↑ Moses Bruines Cotsworth, Calendar Reform (London: The International Fixed Calendar League, 1927), Preface.
  9. ↑ Benjamin J. Elton (February 24, 2012). "Calendar Reform and Joseph Herman Hertz". Jewish Telegraphic Agency . Retrieved October 4, 2019.
  10. ↑ Journal of Calendar Reform volume 16, number 4 (1944): 165-66

Sources

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