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    Breed's Graphical Navigation
    From: Hanno Ix
    Date: 2015 Feb 26, 16:16 -0800
    Francis, Frank,

    there is a neat little booklet in my possession that deals with graphic sight reduction. It does avoid trigonometry and is understandable to anyone who can read. I have attached the title page and the page demonstrating the principle.

    "Navigation without Numbers"
    Joseph B. Breed III , W.W.Norton&Co  NY 1955

    Again, if it is not on the list's collection of books and if it is legal to do so I could make a copy. Unfortunately it is quite annotated but the annotations seem sensible.


    On Thu, Feb 26, 2015 at 1:56 PM, Lars Bergman <NoReply_Bergman@fer3.com> wrote:

    The use of cartesian coordinates, vector algebra and complex numbers are powerful tools to solve spherical trig problems. However, they are generally difficult to solve by hand. 

    I have derived a solution to the problem "find the intersections of two circles of position" by spherical trig formulas suitable for use with logarithms. As is shown in enclosed file the method is quite straightforward. A few logs are re-used which lessens the work somewhat. I have used the same example as in Robin Stuart's paper and the result is pretty near "the truth", with 5-figure logs.

    Lars 59N 18E



    Attached File:

    (Finding-the-intersections-of.pdf: Open and save or View online)


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