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    Re: Leap year
    From: Chuck Taylor
    Date: 1999 May 09, 1:38 PM

    On Sun, 9 May 1999, Doug Bamford wrote:
    > Why is 1800 not a leap year? I always thought the method of identification
    > was the year must be divisible by 4.
    > 1800 is in that category, is it not?
    It takes ~365.24 days for the earth to complete its orbit around the sun.
    If it were exactly 356.25 days, then making every 4th year a leap year
    would make things come out even. That was the premise of the Julian
    calendar, which was used from the time of Julius Caesar to the mid 1700's.
    The problem was that the extra 0.01 day threw things off over time and the
    calendar and the seasons drifted out of alignment. Hence, the Gregorian
    calendar, named for the pope at the time. The rules are now:
    1. Years divisible by 4 are leap years, except
    2. Years divisible by 100 are NOT leap years, except
    3. Years divisible by 400 ARE leap years.
    So, 1800 and 1900 were not leap years, but 2000 will be a leap year.
    Chuck Taylor
    Everett, WA, USA

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