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    Re: Latitude by Lunar Distance
    From: Frank Reed CT
    Date: 2006 Oct 09, 14:42 -0700

    Dan W you wrote:
    "Is there a slight typo in Frank's final position?  My lines appear to
    cross at 69:24W, 38:43N vice his 69:25W, 38:46N.  The 24-25 could
    certainly be my line drawing, but the 43-46 seems to not give the
    correct answer when plugged back into Frank's lunar reduction web
    calculator."
    
    The position fix that I posted was determined by reading directly off a
    little two-inch wide plot in a notebook. I had used a bit of code to
    generate a random position near the DR and then hide it from me.
    Decoded that position was 38d 44'N, 69d 25.5'W. So your plotting was
    correct.
    
    "(ver 4 is current?, ver 5 seems to exist but not work, ver 3 also
    broken?) (source of calculator available?)"
    
    The version that links from the main page
    www.HistoricalAtlas.com/lunars is the current version. If you are able
    to find others by varying URLs, they are either obsolete or not ready
    for primetime --don't use them. I don't want to make the code available
    since there are a few "clever tricks" (from a coding perspective, that
    is), however I can answer any questions you may have about how the
    calculation works. In general, it's just what you would expect, I
    think.
    
    While I'm here, in another post you mentioned Cotter's reference to the
    long, excellent article by "Mendoza del Rios" [sic] in the Transactions
    of the Royal Society for 1797. I am sure that Cotter never read this
    paper since it does not say what he says it says, for one thing, and
    for another that's not the author's name. The "del Rios" part is a
    Cotter-ism. His name was Jose (sometimes spelled Josef) de Mendoza y
    Rios in Spanish language sources and his own pen. Since he spent his
    most productive years in England, his name was often anglicized as
    "Joseph Mendoza Rios". Other navigation authorities in the era
    generally refered to him as "Mendoza Rios". No del! ...The paper is
    worthy of a thread of its own...
    
    -FER
    PS: I am posting this message from the google web interface, rather
    than sending it to the list as an email. Be forewarned: google does not
    yet deal with the "NavigateAway" issue. What that means is that if
    you're typing a message and you click something that takes you to a new
    page to view or google decides you need to log in again for some
    reason, when you "navigate away" you will lose all your typing with no
    warning. A simple way to deal with this is to copy your text to the
    clipboard just before posting (or work in a text file).
    
    
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