YorksPast

This graphic notes we celebrate February 29 nearly every four years. Leap Year was introduced in 46 BC as every four years because it was determined that Earth took 365.24219 days to circle the Sun. Three years at 365 days plus the fourth year at 366 days averages to 365.25 days; which was thought to be close enough.

This little greater time of 365.25 – 365.24219 = 0.00781 days accumulated over the centuries such that by the sixteenth century, calendar dates had fallen ten days behind the position of the sun. A leap day every four years was a little too much of a calendar correction. The centennial year modification was instituted to prevent this shift between calendar dates and position of the sun, such that only one out of every four centennial years was allowed to be a leap year. For example 1700, 1800 and 1900 were not Leap Years, but 2000 was a Leap Year.

The article “A LEAP DAY IN 1916,” provided some well explained additional details in the December 31, 1915 issue of The York Daily. The full text from that article follows:

“While the chief winter holidays, Christmas and New Year’s Day, befall this season on Saturday they will not occur on Sunday a year hence, as would naturally be the case. By the addition of an intercalary or leap day in 1916 that year will contain 366 days and each day after Feb. 29 will fall a day of the week later than it would if the coming year were of the customary length. That is, three years out of every four contain 365 days each and each year whose number is evenly divisible by four is a bissextile or leap year.

“But a year marking the end of a century, as 1900, although divisible by four, was not a leap year, as it was not divisible by 400, only one out of four centennial years being thus leap years, as 2000 will be. These modifications of the so-called Julian calendar, the adoption of which in the great Roman Empire is credited to Julius Caesar, made when Pope Gregory XIII was supreme pontiff, were due to a desire to have the actual dates coincide with the seasons.

“By the error of having every fourth year a leap year, in the sixteenth century, the official dates had fallen ten days behind the sun in the movements through the signs of the zodiac. By the Gregorian calendar, which was adopted in the countries owning allegiance to the Pope of Rome, ten days were dropped upon its promulgation in 1582, the 5th of October becoming the 15th, but in England and her colonies the change was not effected until 1752, when eleven days had to be dispensed with by jumping the dates forward. Russia, owning allegiance to the Greek Church, has not yet reformed its calendar and is now thirteen days behind the rest of the Christian world, and so observes Christmas on our Jan. 7.

“The additional day inserted in the Julian calendar every four years was called bissextile. This was due to the fact that the sixth day before the Kalends of March, Feb. 24, was repeated, so it became the second of that date. But this caused so much confusion that it was later made the last day of February, the shortest month. To it the name of leap year is given because each day following it in the year leaps forward. An almanac quaintly says of it, ‘Children born today will have few birthdays.’”

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