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    Re: Chronology of Celestial Navigation and Related Topics
    From: Antoine Couëtte
    Date: 2018 Jun 8, 05:01 -0700

    RE : Chronology-Celestial-Navigation-Related-Topics-EdPopko-jun-2018-g42189

    Wonderful, Ed !

    May I simply suggest to add :

    1 - The name of the (French ?) Astronomer and the date of publicaiton of the General Mathematical Solution for Lunars as seen from the Earth assumed to be spherical as per the enclosed drawing.

    NOTE 1 - Frank very clearly refered to it - i.e. to the drawing and its derived Formulae (1) and (2) - a few months back, and he indicated that it was discovered a French Astronomer but did not then recall who and when.  In a more remote post - re : http://fer3.com/arc/m2.aspx/math-clearing-lunars-FrankReed-jun-2015-g31648 - Frank also depicts it as the "Direct Triangle Solution" . In other words who discovered this Direct Triangle Solution and when  ???

    NOTE 2 - In my memory, this was published as early as very early 18th Century or even during late 17th century.

    NOTE 3 - In my understanding of Lunars the Direct Triangle Solution has been the basis for all (***) subsequently derived "Classical" Lunar distances methods both in the XVII th and XVIII th Centuries. Quite simple to directly solve to-day with a simple calculator, but much more difficult to solve a few centuries ago !

    (***specific point to be confirmed, Frank, here ???

    2 - The date of publication of the Intercept Method - around 1875 as I can recall - and the name of its inventor.

    French Navy Commander (then) Marc Saint Hilaire is the most commonly quoted author for such universally adopted "Intercept Method", although there are serious reasons to think that it was actually discovered slighly earlier and pioneered by somebody else in France (Maybe Villarceau ??).

    Well done again, Ed !

    Antoine Marie Couëtte

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