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    Re: magnetic variation calculator
    From: Bill Murdoch
    Date: 2005 Feb 24, 20:12 EST
    In a message dated 2/24/05 8:05:51 P.M. Eastern Standard Time, WSMurdoch@AOL.COM writes:
    I'm puzzled. Bill implies that there was no change in variation with
    longitude? (Both locations showing variation of -3.797 deg, though 1 degree
    apart in longitude?). Was that what he meant to write?
    You are right George.  I got the numbers wrong.  For a one degree change in longitude at my location the declination changes from -3.797 to -3.029 or about 3/4 of a degree. 
    Of course it was tongue in cheek.  It is pure happenstance that I have a significant change of declination with latitude at my location.  And, the measurement of azimuth at sea to the required accuracy would be difficult at best.  And, I wonder about the accuracy of the model (A mountain called Iron Mountain is just to the east of me.).  And, no doubt it has taken a couple of centuries of data gathering to support the model.
    But, it is fun to play.
    Bill Murdoch
    It is obviously not my night.  "change of declination with latitude"  should have been "change of declination with longitude".
    Bill  Murdoch
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