"Thirty Days Hath September", or "Thirty Days Has September", [1] is a traditional verse mnemonic used to remember the number of days in the months of the Julian and Gregorian calendars. It arose as an oral tradition and exists in many variants. It is currently earliest attested in English, but was and remains common throughout Europe as well. Full:
Thirty days has September,
April, June, and November,
All the rest have thirty-one,
Save February at twenty-eight,
But leap year, coming once in four,
February then has one day more.
An alternative version goes:
Thirty days hath September,
April, June, and November,
All the rest have thirty-one,
Except February, twenty-eight days clear,
And twenty-nine in each leap year.
The irregularity of the lengths of the months descends from the Roman calendar, which came to be adopted throughout Europe and then worldwide. The months of Rome's original lunar calendar would have varied between 29 and 30 days, depending on observations of the phases of the moon. [2] Reforms credited to Romulus and Numa established a set year of twelve fixed months. Possibly under the influence of the Pythagoreans in southern Italy, Rome considered odd numbers more lucky and set the lengths of the new months to 29 and 31 days, apart from the last month February and the intercalary month Mercedonius. [2] Its imperfect system and political manipulation of intercalation caused it to slip greatly out of alignment with the solar year, [3] which was known to consist of 1⁄4 of 1461 days (rather than 1460 days) by the time of Meton in the 5th century BC. Rather than adopt a new system like the Egyptian calendar, which had 12 months of 30 days each and a set, annual intercalary month of 5 days, Caesar aimed for his 46 BC reform to maintain as much continuity as possible with the old calendar. [4] Ultimately, Mercedonius was removed, the four existing 31-day months were maintained, February was left unchanged apart from leap years, and the needed additional ten days of the year were added to the 29-day months to make them either 30 or 31 days long. [5]
By the Renaissance, the irregularity of the resulting system had inspired Latin verses to remember the order of long and short months. The first known published form [6] appeared in a 1488 edition of the Latin verses of Anianus: [7]
June, April, September, and November itself |
In 2011, the Welsh author Roger Bryan discovered an older English form of the poem [8] written at the bottom of a page of saints' days for February within a Latin manuscript in the British Library's Harleian manuscripts. He dated the entry to 1425 ±20 years. [9] [10] [11]
Thirti dayes hath Novembir | Thirty days have November, |
The first published English version [6] [12] appeared in Richard Grafton's Abridgment of the Chronicles of England in 1562 [13] as "A Rule to Know How Many Dayes Euery Moneth in the Yere Hath": [14]
Thirty days have November, |
"September" and "November" have identical rhythm and rhyme and are thus poetically interchangeable. [1] The early versions tended to favour November and as late as 1891 it was being given as the more common form of the rhyme in some parts of the United States. [15] It is less common now and September variants have a long history as well. A manuscript copy of the verse from c. 1555 [16] runs:
Thirty days hath September,
April, June, and November;
All the rest have thirty-one,
Excepting February alone,
And that has twenty-eight days clear
And twenty-nine in each leap year. [17]
An alternate version of this verse, published in 1827, runs:
Thirty days hath September,
April, June, and November;
All the rest have thirty-one,
Excepting February alone.
To which we twenty-eight assign,
Till leap year gives it twenty-nine. [18]
Another version, published in 1844, runs:
Thirty days has September,
April, June, and November;
All the rest have thirty-one,
Excepting Feb-ru-a-ry alone,
Which has twenty-eight, nay, more,
Has twenty-nine one year in four. [19]
Another English version from before 1574 is found in a manuscript among the Mostyn Papers held at the National Library of Wales in Aberystwyth. [10] [8]
Variants appear throughout Europe. The typical Italian form is: [20]
Trenta giorni ha novembre | Thirty days have November, |
The various forms of the poem are usually considered a doggerel nursery rhyme. [14] In the c. 1601 academic drama Return from Parnassus , Sir Raderic's overenthusiastic appreciation of its poetry [21] is of a piece with his own low level of culture and education. [22]
It has, however, also earned praise. It has been called "one of the most popular and oft-repeated verses in the English language" [10] and "probably the only sixteenth-century poem most ordinary citizens know by heart". [14] Groucho Marx claimed "My favorite poem is the one that starts 'Thirty Days Hath September...', because it actually means something." [10] On the other hand, the unhelpfulness of such an involved mnemonic has been mocked, as in the early-20th-century parody "Thirty days hath September / But all the rest I can't remember." [23] It continues to be taught in schools as children learn the calendar, [1] although others employ the knuckle mnemonic instead.
"Thirty Days Hath September" is also occasionally parodied or referenced in wider culture, such as the 1960 Burma-Shave jingle "Thirty days / Hath September / April / June and the / Speed offender". [24]
The French Republican calendar, also commonly called the French Revolutionary calendar, was a calendar created and implemented during the French Revolution, and used by the French government for about 12 years from late 1793 to 1805, and for 18 days by the Paris Commune in 1871, and meant to replace the Gregorian calendar.
The Julian calendar is a solar calendar of 365 days in every year with an additional leap day every fourth year. The Julian calendar is still used as a religious calendar in parts of the Eastern Orthodox Church and in parts of Oriental Orthodoxy as well as by the Amazigh people.
A leap year is a calendar year that contains an additional day compared to a common year. The 366th day is added to keep the calendar year synchronised with the astronomical year or seasonal year. Since astronomical events and seasons do not repeat in a whole number of days, calendars having a constant number of days each year will unavoidably drift over time with respect to the event that the year is supposed to track, such as seasons. By inserting ("intercalating") an additional day—a leap day—or month—a leap month—into some years, the drift between a civilization's dating system and the physical properties of the Solar System can be corrected.
A month is a unit of time, used with calendars, that is approximately as long as a natural phase cycle of the Moon; the words month and Moon are cognates. The traditional concept of months arose with the cycle of Moon phases; such lunar months ("lunations") are synodic months and last approximately 29.53 days, making for roughly 12.37 such months in one Earth year. From excavated tally sticks, researchers have deduced that people counted days in relation to the Moon's phases as early as the Paleolithic age. Synodic months, based on the Moon's orbital period with respect to the Earth–Sun line, are still the basis of many calendars today and are used to divide the year.
The Roman calendar was the calendar used by the Roman Kingdom and Roman Republic. Although the term is primarily used for Rome's pre-Julian calendars, it is often used inclusively of the Julian calendar established by the reforms of the Dictator Julius Caesar and Emperor Augustus in the late 1st century BC.
The Coptic calendar, also called the Alexandrian calendar, is a liturgical calendar used by the Coptic Catholic Church and also used by the farming populace in Egypt. It was used for fiscal purposes in Egypt until the adoption of the Gregorian calendar on 11 September 1875. This calendar is based on the ancient Egyptian calendar. To avoid the calendar creep of the latter, a reform of the ancient Egyptian calendar was introduced at the time of Ptolemy III which consisted of adding an extra day every fourth year. However, this reform was opposed by the Egyptian priests, and the reform was not adopted until 25 BC, when the Roman Emperor Augustus imposed the Decree upon Egypt as its official calendar. To distinguish it from the Ancient Egyptian calendar, which remained in use by some astronomers until medieval times, this reformed calendar is known as the Coptic or Alexandrian calendar. Its years and months coincide with those of the Ethiopian calendar but have different numbers and names.
As a moveable feast, the date of Easter is determined in each year through a calculation known as computus. Easter is celebrated on the first Sunday after the Paschal full moon. Determining this date in advance requires a correlation between the lunar months and the solar year, while also accounting for the month, date, and weekday of the Julian or Gregorian calendar. The complexity of the algorithm arises because of the desire to associate the date of Easter with the date of the Jewish feast of Passover which, Christians believe, is when Jesus was crucified.
Calendar reform or calendrical reform is any significant revision of a calendar system. The term sometimes is used instead for a proposal to switch to a different calendar design.
A leap week calendar is a calendar system with a whole number of weeks in a year, and with every year starting on the same weekday. Most leap week calendars are proposed reforms to the civil calendar, in order to achieve a perennial calendar. Some, however, such as the ISO week date calendar, are simply conveniences for specific purposes.
Piphilology comprises the creation and use of mnemonic techniques to remember many digits of the mathematical constant π. The word is a play on the word "pi" itself and of the linguistic field of philology.
Henry Constable was an English poet, known particularly for Diana, one of the first English sonnet sequences. In 1591 he converted to Catholicism, and lived in exile on the continent for some years. He returned to England at the accession of King James, but was soon a prisoner in the Tower and in the Fleet. He died an exile at Liège in 1613.
The Ethiopian calendar, or Ge'ez calendar is the official state civil calendar of Ethiopia and serves as an unofficial customary cultural calendar in Eritrea, and among Ethiopians and Eritreans in the diaspora. It is also an ecclesiastical calendar for Ethiopian Christians and Eritrean Christians belonging to the Orthodox Tewahedo Churches, Eastern Catholic Churches, and Eastern Protestant Christian P'ent'ay Churches. The Ethiopian calendar is a solar calendar that has much in common with the Coptic calendar of the Coptic Orthodox Church of Alexandria and Coptic Catholic Church, but like the Julian calendar, it adds a leap day every four years without exception, and begins the year on 11 or 12th of September in the Gregorian calendar. A gap of seven to eight years between the Ethiopian and Gregorian calendars results from an alternative calculation in determining the date of the Annunciation.
Mercedonius, also known as Mercedinus, Interkalaris or Intercalaris, was the intercalary month of the Roman calendar. The resulting leap year was either 377 or 378 days long. It theoretically occurred every two years, but was sometimes avoided or employed by the Roman pontiffs for political reasons regardless of the state of the solar year. Mercedonius was eliminated by Julius Caesar when he introduced the Julian calendar in 45 BC.
Richard Grafton was King's Printer under Henry VIII and Edward VI. He was a member of the Grocers' Company and MP for Coventry elected 1562/63.
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A menologium, also known by other names, is any collection of information arranged according to the days of a month, usually a set of such collections for all the months of the year. In particular, it is used for ancient Roman farmers' almanacs ; for the untitled Old English poem on the Julian calendar that appears in a manuscript of the Anglo-Saxon Chronicle; for the liturgical books used by the Eastern Orthodox Church and Eastern Catholic Churches following the Byzantine Rite that list the propers for fixed dates, typically in twelve volumes covering a month each and largely concerned with saints; for hagiographies and liturgical calendars written as part of this tradition; and for equivalents of these works among Roman Catholic religious orders for organized but private commemoration of their notable members.
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The knuckle mnemonic is a mnemonic device for remembering the number of days in the months of the Julian and Gregorian calendars.
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