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    Re: Time Sight Computations
    From: Chuck Taylor
    Date: 2004 Sep 29, 08:24 -0700

    Zorbec and George both have it right.  The first error
    was that I mis-copied the wrong number for log sec of
    Latitude, copying 9.12462 instead of 0.17875.  The
    second error was an addition error, which gave me log
    hav t = 9.22991 instead of the correct value of
    9.22921.  This gives t = 48d 37.6', which is within
    0.1' of the Method 1 result.
    I noticed that the value of log cos s is a bit
    sensitive to the fact that I rounded (164d 41.1')/2 to
    82d 20.6'.  The 5th decimal place of the log cos
    changes by 5 if I do not round.  I then decided to
    carry all the calculations to 10 decimal places on a
    computer.  Here is the result:
    h    24d 54.3'
    L    48d 30.1'     log sec  0.1787497078
    p    91d 16.7'     log csc  0.0001081019
      2)164d 41.1'
    s    82d 20.55'    log cos  9.1246707117
    s-h  57d 26.25'    log sin  9.9257270216
    t                  log hav  9.2292555430
    t    48.628933344d W
    t    48d 37.736' W
    This agrees even more closely with my Method 1
    calculation, as it should.
    Best regards to all,
    Chuck Taylor
    North of Seattle
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