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    Re: Early sextants & Lunars...
    From: Brad Morris
    Date: 2014 Mar 26, 14:04 -0400


    Both of my instruments are vernier type.  Both are divided to 10 arc seconds through the vernier.  The Circle of Reflection has two verniers, and when averaged, yield 5 arc second resolution.

    I don't know if these represent the norm.  Bill Morris has called the Heath Hezzanith as *the finest sextant ever* made.  The Circle of Reflection is such a rare beast that its hard to characterize it within 'normal' sextants.


    On Mar 26, 2014 12:42 PM, "Greg Licfi" <cfi@licfi.com> wrote:

    I think I don't quite understand what the resolution of a pre-micrometer era sextant may have been. Every example that I have seen seems to be a vernier reading out to a resolution of 1' of arc. If this is the case how did they do Lunars that according to what I've read here require a sub-minute resolution of the actual lunar distance? The more I learn the more I learn what I don't know :-)
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