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    Re: Scrap paper with time sights c.1870
    From: Lars Bergman
    Date: 2013 Feb 21, 14:47 -0800

    Frank asked: "How confident are you in the year of the observations?"

    Well, as the subject included "c.1870" I searched a couple of years before and after 1870 and got "the best fit" for declination and equation of time to 1871, December 27th. But as pointed out there was a 2 seconds discrepancy in EoT.

    Since the observation I looked at, top left, was made only 8 minutes before noon GMT, you could expect that the navigator would have used the noon figure for EoT. He (or she ?) used 1m10s, but the NA of 1871 shows 1m12s.

    Now, looking at other years, the same date, we find 1875 1m12s, 1879 1m12s, 1883 1m12s. Going the other way, 1867 1m11s, 1863 1m12s, 1859 1m10s, 1855 1m10s.

    So maybe the year was 1855 or 1859. Is that plausible?

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