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    Re: Sumner's Line (Navigation question)
    From: Bill B
    Date: 2006 Feb 10, 01:53 -0500

    Some Sumner questions:
    
    1. Any guesses what his ship could make on a slightly close reach in heavy
    seas?  Or at least her length at waterline?
    
    2. When the Bowditch excerpt states she was kept "...under short sail, with
    heavy gales..."  does this imply that he had reduced sail to fit conditions,
    or that he shortened sail to cut speed until he had a good idea of position?
    
    3. In playing with the numbers, it seems the longitudinal differences
    between assumed latitudes increases slightly as latitude moves north in
    regular increments.  At first I thought this might be compensated for by the
    increased spacing between parallels on a Mercator projection as the assumed
    latitude moves north.  I have not worked that out to the nth, but on first
    blush it will not cancel out.  The question then is (before I reinvent the
    line, or as the wheel as the case may be)--over a great distance would the
    Sumner LOP actually be a COP on a Mercator projection?
    
    Thanks Bill
    
    
    

       
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