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    Re: Survival Sextant
    From: Peter Monta
    Date: 2018 May 23, 20:28 -0700

    It looks like Sven Yrvind has a new type of Bris sextant in the pipeline under testing. He has proven concept. He calls it a survival sextant. 


    Clever.  I guess it's the relative twist that matters---a global twist of the entire instrument would do no harm because of the double reflection.  Still, it might be less mechanically stable than a Bris.  If one moving part is acceptable, how about a sliding cursor with a sight hole?

    He mentions multiple Bris sextants stacked horizontally.  That sounds pretty good too, and you get inherent high stability.  Each sub-Bris could be spaced from its neighbors by only a few millimeters, so a fair number of angles (a dozen or so?) would still be quite compact.  Grinding multiple glass shims would not be all that burdensome---they're very small.

    Cheers,
    Peter

       
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