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    Re: Mendoza's method for clearing lunars.
    From: George Huxtable
    Date: 2004 Aug 4, 18:18 +0100

    In a message to the list, earlier today, I asked for help about the
    following question.
    "There's a further minor-matter arises, in which any members who has access
    to a pre-1828 version of Norie's may be able to help. In Norie's 1816 text
    about Mendoza's method, which I quoted earlier, He mentions adding "the
    proportional logarithm of the Moon's correction (XXX)". In my own, early
    20th century edition of Norie's, table XXX just gives the Moon correction,
    in minutes and seconds, not the proportional log. of that correction. This
    presents no real problem, because there's a table of proportional logs
    elsewhere, so the required number can be found by a two-step procedure.
    It seems that even as early as 1828 (in the Mystic version), Norie's table
    XXX was the same as in mine. So I ask if anyone can tell me if, in  an
    earlier version of Norie's, (perhaps in the edition current in 1816) table
    XXX contains the Moon correction in minutes and seconds, or whether it
    contains the proportional log of that correction, so the step in Mendoza's
    method can be mode in one go. Conceivably, it might offer columns for both.
    Perhaps I have simply misunderstood Norie's text about the Mendoza method,
    and he intendedd a two-step lookup from the start.
    Please don't send me copies of that table XXX: just a few words about what
    it contains, is all I am after."
    Now I find, after a more careful reading of Norie's text, and examining the
    layout of his standard form for lunars, that I was indeed misunderstanding
    what Norie was stating. In a list of items to be added together, one of
    those items was- "the proportional logarithm of the Moon's correction
    (XXX)". I had taken that to read that table XXX contained the proportional
    log of the Moon's correction: but the evidence shows that to be wrong.
    What he was saying was that you should use table XXX to find the
    correction, then use another table (XXXIV, in fact, though Norie doesn't
    say so) to obtain the prop. log. of the correction. With that meaning, it's
    no surprise that table XXXV remained the same in the early 20th century as
    it was in 1816 and 1828, and there's no discrepancy with Norie's standard
    form for calculating lunars. All is now understood, and I withdraw my
    request for help on that matter.
    contact George Huxtable by email at george@huxtable.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.

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