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    Re: Longitude sight, South Pacific, 1864
    From: Ed Popko
    Date: 2018 May 14, 10:51 -0700

    I have missed an interpretation step in the Elizabeth time sight.

    The total of the logs is 19.33631, dropping the tens is 9.33631 and finding Half Total (hT), not shown in the scrap, is 4.6682 which is usually the logsin(LHA/2). But I can't get there???

    The scrap shows LAT= 05:44:40, thus LHA=86.1667° or LHA/2=43.0833° or logsin=9.8345 and not the 'dropped tens value' I get above.

    I'm stuck on the getting the right: 1) hT log value, 2) dividing it by 2 and 3) finding its logsin value for LHA/2 angle.

    I have reattached Frank's image of it for convenience.

    Any help is appreciated.



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