Why is our leap day in Februrary, not the end of the year?
Romans always reconciled differences between calendar and solar year lengths during the “Month of Purification.” Whenever and however Roman calendars were modified to correspond to year length, it was always done after the 23rd day of February, traditionally the last day of the year. Even in our time, leap year is observed with a 29-day February. To purists, “leap day” is February 24, not the 29th. Plutarch wrote: “Numa…added an intercalary month, to follow February, consisting of twenty-two days, and called by the Romans the month Mercedinus. This amendment, however, itself, in course of time, came to need other amendments.” (When observed, that leap month always immediately followed February 23.) According to historian Livy, Numa divided the year into twelve months, corresponding to the moon’s revolutions. But as the moon does not complete thirty days in each month, and so there are fewer days in the lunar year than in that measured by the course of the sun, he interpolated interca
