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    Re: Bowditch Finds Error
    From: Russell Sher
    Date: 1999 May 10, 02:48 EDT

    Gordon - I understand that the leap year criteria is dependant on whether or
    not the (4 digit) year can be divided (or not divided) by 4, 100 or 400
    --e.g. if divisible by 100 then it is NOT a leap year (I think) e.g 1900 or
    1800 was not a leap year. If divisible by both 400 and 100 - of then
    overides --
    Does someone on the list know more about this??
    Russell Sher
    > -----Original Message-----
    > From: Gordon Talge [SMTP:gtalge@XXX.XXX]
    > Sent: Saturday, May 08, 1999 8:02 AM
    > Subject:      Bowditch Finds Error
    > In the first part of the 1984 edition of Bowditch where it tells
    > about the him and his family, it talks about an error found by
    > Bowditch in the 13th edition of "The New Practical Navigator" by
    > Moore, dated 1798.  To quote, "The most significant error was listing
    > the year 1800 as a leap year in the table of the sun's declination.
    > The consequence was that Moore gave the declination for March 1, 1800,
    > as 7degs 11mins.  Since the actual value was 7degs 33mins, the calculation
    > of a meridian altitude would be in error by 22 mins of latitude."
    > Interestingly enough, I have a copy of the Moore's book dated Jan. 30,
    > 1798,
    > unfortunately the title pages are missing from the book, along with his
    > picture, but the preface states that the book has been through 12 previous
    > editions.
    > I checked the "error" and found that 1800 is not listed as a leap year and
    > it gives the correct declination for March 1, 1800 as 7degs 33mins South.
    > -- Gordon
    >                                      ,,,
    >                                     (. .)
    >          +-----------------------ooO-(_)-Ooo----------------------+
    >          |  Gordon Talge WB6YKK            e-mail: gtalge@XXX.XXX  |
    >          |  Department of Mathematics      QTH: Loma Linda, CA    |
    >          |  Notre Dame High School         Lat.  N  34? 03.1'     |
    >          |  Riverside, CA 92506            Long. W 117? 15.2'     |
    >          |  http://www.pe.net/ND                                  |
    >          +--------------------------------------------------------+

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