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    Re: David Thompson's Navigational Technique
    From: Ken Muldrew
    Date: 2004 Jun 1, 19:55 -0600

    Frank Reed wrote:
    >  2) I can't see where you got a factor of 1/2 out of
    > Maskelyne's instructions. There *is* a factor of 1/2 but it's folded
    > into the "8.73" factor. That factor (besides the 1/2) arises from
    > working in minutes and seconds of arc instead of pure angles (a.k.a.
    > radians). You'll find that 8.73 is pi/360 (with a factor of 1000)
    > which is why Maskelyne says to "abate 13" from the index instead of
    > the more common 10 or 20.
    I got the factor of 1/2 from the "abate 13", 10 for the log cotangent and 3
    for a factor of 2. Anyway, it's all clear to me now. Thanks for the
    Ken Muldrew.

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