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    Re: Accuracy of sextant observations at sea
    From: Gary LaPook
    Date: 2010 Sep 23, 13:19 -0700

      Thanks for that document, it made interesting reading. I noticed that 
    the σ of all the data was 1.53, almost exactly the same as mine which 
    was 1.433. ( I omitted the moonlight observations and the naked eye 
    sunrise observations from my σ since those were not normal types of sights.)
    On 9/23/2010 8:15 AM, George Huxtable wrote:
    > John Brown offereed this following useful comment, about Gary's recent
    > posting.
    > Subject: [NavList] Re: Accuracy of sextant observations at sea
    > These seem to be very good results.  My 1963 edition of Burton's Tables has
    > this to say in the first paragraph of the Notes:
    > "An extensive investigation into the degree of accuracy normally obtained
    > in the practice of astronomical position-finding at sea has indicated that
    > the average inaccuracy in a position line produced by the average observer
    > is 0'.7, and that one in twenty such position lines may be as much as 3'.0
    > in error."
    > ======================
    > I saw that Burton's tables offers this footnote, about that comment.-
    > See "The accuracy of Astronomical Observations at Sea", Journal of the
    > Institute of Navigation, vol X, No 3, July 1957.
    > It's the report of a working party, chaired by Don Sabler, who headed the
    > Almanac Office. They sent out thousands of questionnaires to navigators,
    > and analysed the answers that came back.
    > It adds up to 26 pages, but only 1.4 MB in a .pdf file. If you find it of
    > interest, here it is, attached..
    > George
    > contact George Huxtable, at  george{at}hux.me.uk
    >   or at +44 1865 820222 (from UK, 01865 820222)
    > or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

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