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    Re: 12-power sextant scopes... Why?
    From: David C
    Date: 2024 Jan 5, 19:00 -0800

    This does not answer Frank's question but  in 1921 the US Bureau of Standards required that a sextant have a "long" telescope with two eyepieces giving magnifications of about  6x and 10x. A short telescope provided about 3x magnification.

    Circular 110 Specifications for Marine Sextants.

    https://www.govinfo.gov/content/pkg/GOVPUB-C13-1ad5b7d1264f864b0dbe5aaf881fbf84/pdf/GOVPUB-C13-1ad5b7d1264f864b0dbe5aaf881fbf84.pdf

    The Admiralty Manual of Navigation (AMN) states that the largest power telescope should be used when checking a chronometer on land using an AH. Is this relevant to Frank's question? I do not know.

    An advert in the 1928 vol 1 edition of the  AMN  shows that in that era Husun were manufacturing sextants with 10x magnification.

    Finally to reveal my ignorance. There is a current thread about Husun sextants. I wondered if it was a Japanese brand - was it pre or post war? Then when I was studying the 1928 advertisment I realised that Husun is a contraction of Hughes & Son!!!!!!!!!!!

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