By William L. Steen
Art by Wally Neibart
Leap year can raise some confusing questions. Why does leap year come every four years? Why do we add an extra day to February?
If you lived in Rome two thousand years ago, that extra day wasn't even considered a day at all. Confused? Don't worry. Our modern leap-year tradition started with a year that was even more confusing. It didn't have one extra day; it had ninety. It was known as the "year of confusion."
The year of confusion was put into effect by a Roman leader named Julius Caesar. His goal was not to create confusion but to end the confusion that existed.
Before Caesar's time, the Romans often added or removed days from their calendar without any scientific reason. Caesar wanted to reform the Roman calendar, which had 355 days and which was basically a lunar calendar. But there was a problem--the calendar was so far off track that the months and holidays were no longer in their traditional seasons. For us, it would be like having Thanksgiving in September. This had been caused by decades of sloppy calendar keeping and by the fact that lunar calendars do not follow the seasons. Caesar decided to return the months to their normal seasons before introducing a new calendar.
To do this, Caesar followed the advice of an Egyptian astronomer named Sosigenes and added ninety days to the year that we know as 46 B.C. It became the longest leap year in history!
Caesar divided the ninety extra days into three temporary months. One month was added between February and March. Two other months were added after November. The year 46 B.C. had fifteen months and was 445 days long. No wonder it was called the year of confusion!
In reality, it was the year to end all confusion. It returned the months to their proper seasons and made it possible for Caesar to introduce his reformed calendar, which we call the Julian calendar, in 45 B.C. Taking Sosigenes' advice once again, Caesar made the new calendar a solar calendar, similar to that of the Egyptians. This would help to keep the calendar on track, since solar calendars follow the seasons.
To make the new calendar more accurate, one little bit of confusion was kept. We call it a leap day. It takes the Earth about 365 1/4 days to travel around the Sun. If every calendar year had 365 days, it would be shorter than the true year; if it had 366 days, it would be longer. This problem was solved by adding one extra day--a leap day--to February every fourth year.
At first, this leap day was put between February 23 and 24. It didn't have its own number, and it wasn't even counted as a real day. Eventually leap day was moved to the end of February and given a number. Today February 29 still appears on our calendar every leap year.
A few improvements to the calendar have been made since Caesar's time, but his year of confusion and introduction of a solar calendar ironed out most of the wrinkles.
If you feel that it's confusing to add a day to February every four years, imagine living in the year of confusion!