Auxiliary to Question 17598 to establish my point. George Washington is quoted as being born on 11 February 1732. I presume this to mean the date now known as this and called in England at the time 11 February 1731 the year having started on the previous 25 March. Was the day 18 days later,now known as 29 February 1732 then called 29 February 1731 or 1 March 1731 putting the days between the two styles out of phase for 12 months?

Gnomon

There seem to have been two different years in use. The historical year ran from 1 Jan to 31 Dec while the Civil Year ran from 25 Mar to 24 Mar. Between 25 Mar and 31 Dec, the two years were identical. The leap years seem to have been based on the Historical year. You can read about this at http://www.genfair.com/dates.htm. The postscript mentions this problem specifically and gives the answer I have just stated, but it is not definite about it. Mar 25 02, 2:12 PM

Fosse4

Agree with you Gnomon, the year number didn't change with the changeover from Julian to Gregorian, however the celebration of New Year moved from March to January. Facts about New Year can be found onhttp://www.celebratetoday.com/newyears.html Mar 25 02, 6:47 PM

Gnomon

There was a change of the way the years were numbered for recording purposes. The day before 25 March 1722 was 24 March 1721. But this was usually written 24 Mar 1721/2. It appears to have been the latter date that was used to calculate the leap years. Mar 25 02, 10:16 PM

Tabby Tom

Gnomon is right. The Julian calendar reform provided for a leap year every fourth year with the extra day falling in February. So every fourth February from 45 B.C. onwards had an extra day so long as the Julian calendar was used. At different times the years have been numbered in all kinds of ways, but there was always an extra day every fourth February. Thus there were 29 days in February of the 2,485th (Roman) year from the foundation of Rome. In England, and in the overseas possessions, the days from 1st January to 24th March in this year were officially part of 1731 (which had begun on 25th March in the previous Roman year) and the days from 25th March onwards were part of 1732. Under Lord Chesterfield's Act of Parliament of 1751, the day after 31st December 1751 became 1st January 1752 (it would otherwise have been 1st January 1751). The calendar was adjusted to the Gregorian system in September of that year. Modern historians normally date pre-Gregorian years according to the modern reckoning. So if a modern reference book gives Washington's birthday as 11th Feb 1732, it almost certainly means what you and I mean by that date. But at the time, in England and Virginia, it would have been officially called 11th February 1731. The 'leap day' 18 days later would have been called 29th February 1731, but will now be called 29th February 1732. Historians don't usually convert pre-Gregorian dates within a year to Gregorian ones, so Washington's birthday would have been called 22nd February if he had been born in a country using the Gregorian calendar. (Sources: Oxford Companion to the Year: Oxford Companion to English Literature - Appendix II (The Calendar). Mar 26 02, 11:30 AM