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    Crelle's tables
    From: David C
    Date: 2020 Sep 26, 19:10 -0700

    I wonder if I have found yet another way of solving the navigational triangle? While looking at the list of pdfs I had downloaded I came across one called

    The Mathematics of Navigation E J Willis  1921


    Because I had ssumed that it was just another navigation text I had not looked at it.  When I glanced at it today I realised that it is of more interest than a standard navigation text. The author believes that the navigational triangle should be solved by plane trigonometry and differental calculus. He seems to be anti-logs. The only tables needed are natural trigs and Crelles and a 20" slide rule. Martelli seems acceptable.  Here is how he begins in a discission about the haversine method:

    In order to "simplify"(?) they usually make use of the fact that haversine X =...............

    Crelles tables can be downloaded at


    I do not know if Willis' method works or how easy it is to use. I do not understand it.  My interest has been in locating a copy of Crelles tables which I had not heard of before. I have searched the navlist archives and did not get a hit for Crelle. The only paper copy I could find was a 21st century reprint on demand  [1].  I am posting this method so that the method is searchable.

    [1] Is it possible to remove on demand  reprints from book searches?

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