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    Re: Longitude sight, South Pacific, 1864
    From: Ed Popko
    Date: 2018 May 12, 14:01 -0700

    Many interruptions on my end but some progress in analyzing part 3 addition of this South Pacific case.

     In the Sun Moon Dist  App Dist area, I interpreted:

    Dist Column

    - pre-cleared Lunar ends up 117°49'16" after both semi-diameters. Can't account for the 1' subtraction, certainly not augmentation which would have been additive.

    App Dist Column

    - LDpc carried over to Dist column, four corrections later. 2nd corr is large, likely effect of HP on LD's arc.

    - 3rd corr is small, likely sun's impact on LD's arc.

    - Cleared lunar is 117°11'28"   checked against several methods which find 117°11'48" so corrections were about right.

    - 116°28'02 is LD at 0Hr, though not stated, using PLog values written, 118°08'27" is LD at 3hr

    - 63'26" is LD difference between LDpc and 0hr LD

    - 2535 is PLog of LD 3hr

    - 6174 is PLog of LD 0hr

    - 3639 is PLog 0hr-3hr    No idea why it was over written to read 3439.    The original value, 3639, seems correct.

    - LDc is 1.2976 (decimal) hours added to 0hr is 1:17:50  but table lookups might give 1:17:53 as shown here

    - LDc GMT is 1:17:53 corrected for Civil Time 12:17:53

    Much more to be extracted from this case.  Quite interesting and Frank, thanks for posting this.

    Ed Popko

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