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    Ogura's Short Method for Altitude (aka Nories' A_K table)
    From: David C
    Date: 2020 Apr 21, 00:01 -0700

    Norie's Short Method for Zenith Distance, also known as the A_K table, was first included in the 1924 edition of Norie's tables. The table was used with the permission of Capt Ogura of the Japanese Imperial Navy.  Sometime In the 1950s or 1960s the table was re-designed to also provide azimuth. By 1983 the table had disappeared from Norie. I have worked a sight using the 1943 edition of Norie because that year the table was in the original form as devised by Ogura.

    There are three points to note:

    1. The table provides zenith distance only. Azimuth must be obtained by another method. That could conveniently be by the ABC tables, which have long been included in Norie, or  by Burdwood or Davis.

    2. Two tables are used. The A_K table and a log secant table.

    3.  The assumed latitude and longitude must be to the nearest degree.



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