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    Re: HO 214 History
    From: Frederick Curtis
    Date: 2021 Nov 18, 14:31 -0800

    Shortly before publication of H.O. 229 an article appeared in the journals of both the American and the British Insttutes of Navigation on the use and justification for these new tables. Authored by;

    J.H. Blythe, Director of the Navigational Science Division of the U.S. Naval Oceanographic Office.


    Dr. R.L. Duncombe, head of the Nautical Almanac Office of the U.S. Observatory.


    D.H. Sadler, Superintendent, H.M. Nautical Almanac Office, Royal Greenwich Observatory.

    (IMHO that appears to be "expert opinion", LOL)

    This is one paragraph I quote,

    "Although H.O. Publication No. 214 is far from perfect, its imperfections do not significently affert its use for navigation. There are about 1&1/4 million entries in these tables, and they were calculated at a time before even punch-card computers were available: essentially each value had to be calculated individually with seperate entry into the appropriate trigometrical tables.  It is not surprising that there are minor end-figure and rounding-off errors; the large errors, mainly introduced in the process of the printing, have already been found and corrected. Moreover, the design of the tables, particularly in respect of the provisions for interpolation, is not the most suitable for obtaining the full tabular precision of 0.'1; the limitation to altitudes greater than 5 degrees has also been found restictive in some applications."

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