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    Re: Modified Martelli Table V
    From: Greg Rudzinski
    Date: 2013 Jan 2, 16:44 -0800

    Frank,

    Table 34 in the 1984 vol. II seems to work as you have pointed out. 11.0334 - Log Hav table 34 = Martelli table V . This is easier than a time to arc conversion but not as good as a direct table look-up which still requires number crunching to construct from table 34. Good find though.

    Greg Rudzinski

    [NavList] Re: Modified Martelli Table V
    From: Frank Reed
    Date: 2 Jan 2013 15:39
    Hewitt, you wrote:
    "Great going, Greg. Many thanks for this. Is there a way to download so it can
    be printed? I don't have a printer, so need to put it on a memory stick and
    take to a copy shop."

    There's a good chance you already have the equivalent in a familiar book. If you have a copy of Bowditch from about 1910 to 1962 (not sure on the exact date limits), it has Table 34 which is tables of haversines and log haversines. Because of the "weirdness" of Martelli's mixed up tables, there's an odd constant to deal with, but you can get any value in the table Greg calculated simply by taking the loghav value from Table 34 of Bowditch and subtracting it from 11.0334. Every number in Greg's newly calculated table is just 11.0334 minus the corresponding value from Bowditch Table 34. As I noted previously, Martelli's tables can be easily re-engineered without all his weird constants (no 11.0334 after that) and when you're done you'll find that the tables are almost all already present in mid-century editions of standard navigation manuals. Notice also that the hav(t) tables in editions of Bowditch before the big overhaul released in 1958 are double entry: you can look for the LHA in degrees or in hours and minutes of time. By the 1950s, actual time sights, requiring the entries in hours and minutes, were "officially" if not quite over and done with in practice.

    -FER

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