29 February 2012

Leap Day

Today is that most exciting of days – February 29. Leap Days occur to keep our calendar of 365 days in line with the reality that is the Earth’s orbit around the Sun, which takes 365.24219 days.
Julius Caesar made a good stab at solving this discrepancy with his Julian Calendar of 365.25 days. There is some debate about where and how he inserted his Leap Day, but most likely it was achieved by having February 23 twice. During the late Middle Ages this evolved into the custom of having a February 29 every 4 years.
But don’t we still have a Leap Day every four years? After all we’ve got the rhyme:

Thirty days hath September,
April, June, and November;
All the rest have thirty-one,
Save February, with twenty-eight days clear,
And twenty-nine each leap year.

Slippery, no? The rhyme doesn’t actually specify when the Leap Day occurs. If it did we’d have to tack something on the end along the lines of:

Which are those divisible by 4,
But not those by 100,
Excepting those divisible by 400.

Feel free to fix up the rhyming and scansion there. Still, better than this 16th Century version:

Thirtey days hath November,
Aprile, June, and September:
Of twyecescore-eightt is but eine,
And all the remnante be thrycescore-eine.
O´course Leap yare comes an´pynes,
Ev'rie foure yares, gote it ryghth.
An´twyecescore-eight is but twyecescore-nyne.

Anyway, the difference between the Julian Calendar and reality meant that each day was 11 minutes off. Pope Gregory instituted our current Gregorian Calendar in 1582, at which point the cumulative inaccuracies of the Julian Calendar were such that people went to bed on Thursday, October 4 and woke up on Friday, October 15 (spare a thought for the Greeks, by the time they adopted the Gregorian Calendar in 1923 they had to drop 13 days)
So, a happy birthday to all those born today, the Leaplings as you are called, with your furry tails and cute little snouts. Your peers include such luminaries as serial killer Richard Ramirez, motivational hack Tony Robbins and rapper/actor Ja Rule.
A special mention too, for James Milne Wilson, Manager of the Cascade Brewery, Mayor of Hobart and Premier of Tasmania. Admired by Anthony Trollope, he was not only born on February 29, but died on that day too, his “17th” birthday.