These are happy times for those who must celebrate their birthday every four years. This year, February gains an extra day.
The leap day is needed to keep our calendar in step with the sun’s year, which is 365 days and six hours long. This correction is one of those things that the Romans did for us.
The calendar of their ancient Republic was based on the moon’s cycle, and like all lunar calendars it moved gradually through the solar year. So in 46BC Julius Caesar ordered a revision. The Romans adopted a solar calendar of 365.25 days, with the shortfall made up by adding one whole day every fourth year.
Although the Julian year worked well enough, it had a fault. Its solar year was slightly too long, so that over time the astronomical year drifted away from the religious calendar.
By the 1570s the difference was four days. This led to problems with the date of Easter, which falls on the Sunday after the full moon that follows the spring equinox. Christmas was affected too because it relates to the winter solstice, and so was the birthday of St John at the summer solstice.
Pope Gregory XIII appointed a calendar commission to sort things out. One of their recommendations was that a centennial year should only be a leap year when it is divisible by 400. That’s why the year 1900 was not a leap year, while 2000 was.
A big leap
The one thing most of us know about leap years is that this is when a woman can propose to a man. The Ladies’ Privilege, as it was known, hardly seems revolutionary now. Nevertheless, in the days when the roles of the sexes were rigidly defined, the very idea was inflammatory.
For centuries women were expected to take what was offered, rather than choosing for themselves. And it wasn’t unknown for a man to keep a woman hanging on for years in the hope of a proposal that never came. Yet it’s impossible to know how many women, if any, claimed the right to propose in a leap year. Exactly when the ladies’ privilege began is not known either, but in 1606 it was mentioned in a book called Courtship, Love, and Matrimony.
Further back than that we enter the realm of legend. When St Bridget met St Patrick, she complained that women did not have the right to propose. Reluctantly, Patrick made an offer that would allow this once every seven years, but feisty Bridget beat him down to one in four.
Like a lot of customs, the ladies’ privilege has acquired its own folklore. Queen Margaret’s law of 1288, said to enshrine the privilege in Scotland, is a myth. And there’s no evidence either for the English belief that the woman must wear a red petticoat while proposing, or that the man who refuses must compensate her with the gift of a silk gown. If that were true, every single woman could have filled her wardrobe with fine dresses.
The myth making didn’t end with clothes. There was a common belief that plants, especially broad beans, would “grow the wrong way” during a leap year.