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    Re: Longitude by lunar altitudes
    From: Brad Morris
    Date: 2010 Jan 5, 19:22 -0800

    Hi George

    I followed your link and indeed, that is one of the two methods refered to. Turn the page back to page 207 for the other method.

    No need for you to apologize for my memory (or lack thereof). I couldn't remember the author or the name of the text, but I could remember those odd methods. Frank and you both assumed it was Chauvenet on very resonable evidence. I should have just held off posting until I could reference the text.

    My 1856 copy has a handmade book cover made out of sail cloth! Its in great shape. Aparently a student attended Thoms classes that year, because he put his name and wrote the date (1856) inside the cover. The publication date printed is 1856 as well. Its a genuine time capsule.

    Thoms statement of the precision of the method damns it as useless. After working that lengthy computation (see page 208), one can only expect to know one's longitude within a degree. The uncertainty of the result, when compared to the accuracy of a true lunar or longitude by chronometer would have relegated this method to the 'interesting but useless' pile nearly right away.

    Best Regards
    Brad Morris

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