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What is a leap year?

Today, 29 February 2012, is a ‘leap day’. To understand more about the leap phenomenon, and the significance of 29 February in history, we turn to The Oxford Companion to the Year: an exploration of calendar customs and time-reckoning.

29 February

Leap Day. In the modern form of the calendar, which dispenses with the Roman names of days, this is leap day, inserted every four years to make up the difference between the common year of 365 days and the solar year; by happy accident the sequence of leap years inherited from the Romans coincides with years AD divisible by 4. Since the true difference is some eleven minutes less than six hours, Pope Gregory XIII ordered in 1582 that leap day should be omitted when the year was divisible by 100 but not by 400; the years affected, in those countries that accepted the reform (which Great Britain did not till 1752), were 1700, 1800, and 1900. There was a 29 February again in 2000, but will not be in 2100.

Persons born on 29 February are humorously said to have a birthday only once in four years; on that basis Rossini, who was born on 29 February 1792, would have waited till 1804 for his second birthday, since 1800 was a common year. In practice, however, they have birthdays in common years on the 28th. By the legal rule noted under the 22nd, anyone born on either 29 February or 1 March 1948 in England (though not Scotland) came of age on 28 February 1969; but since the Act that abolished that rule also reduced the age of majority, persons born on 29 February 1952 came of age on 28 February 1970, but those born the next day not till 1 March.

Western saints such as Oswald of Worcester who died on 29 February used to be culted on that day in leap year and 28 February in common years; this was a last relic of the Roman reckoning, which made the last day of February pridi Kalendas Martias in either case. By contrast, the Orthodox church, which uses the forward count, celebrates John Cassian on 29 February in leap year and not at all in common years, reputedly as punishment for being last to arrive when the saints came to ask Christ for work. In Mytilene this is the shirkers’ feast, and Cassian holds the keys of idleness.

An old Scotswoman in the nineteenth century, asked by a small boy why this day occurred only once in four years, consulted the ‘funtin-heid’, her Bible, which fell open at Job 3: 3, ‘Let the day perish wherein I was born’, and deduced that Job had been born on 29 February; the Lord had not altogether abolished that day, but done what he could for his servant by suppressing it three years out of four. That was mere fancy, but we read in a near-contemporary that in the second century AD the Athenians gratified the multimillionaire Herodes Atticus – or rather yielded to his unrestrained emotionalism and much-resented power – by removing from the calendar the day on which his daughter died.

29th February
A day added to the year,
laconic or luminous.
The extra day can be seen
and touched, like any other.
Its hours are not difficult to count,
the weather varies but is weather,
no alien manifestation.
Lovers who marry on this day
have the usual eggshell hearts,
the lewdness of fish.
Children born on this day
are as fierce as any others.
Those who die on this day
must find new ways of being,
and on this day
singing still builds
the upstairs room of the sky.
This is the day
the year keeps for herself
but offers to you,
her breath for yours,
fair exchange.

Penelope Shuttle (1947- )

On this day, in England and Denmark, a woman has the traditional right of asking a man to marry her; compare Sadie Hawkins Day (first Saturday in November) in the USA and Sainte-Catherine (25 Nov) in France:

IOCULO: Maister, be contented, this is leape yeare,
Women weare breetches, petticoats are deare.
John Lyly, The Maydes Metamorphosis (1600).

On 29 February 1504 there was a lunar eclipse, predicted by the great astronomer Johann Müller of Königsberg (‘Regiomontanus’); Colombus, who took an interest in eclipses as possible indicators or longitude, when stranded on Jamaica during his fourth voyage used that foreknowledge to secure food for his crew from the inhabitants by announcing before the eclipse that the moon would rise dark and bloody in sign of God’s displeasure, and declaring after it that his prayers on their behalf had been answered. Mark Twain exploited this story in A Connecticut Yankee at the Court of King Arthur, H. Rider Haggard in King Solomon’s Mines.

This excerpt is taken from The Oxford Companion to the Year by Bonnie Blackburn & Leofranc Holford-Strevens.

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