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    Re: John Wesley Powell River History Museum
    From: Robin Stuart
    Date: 2021 Oct 30, 09:33 -0700


            Thanks for posting this more realistic picture. I assume that is the mercury flask that can be seen on the ground to his left. The artificial horizon seems to have glass side walls which is probably not correct.

    I have to take back my earlier statement about the problems with the sextant in the sculpture, "The telescope is horizontal but the arc is not symmetrical about the vertical." Looking at a number of examples it appears that modern sextants tend to have the telescope and horizon mirror mounted at the same distance from the central axis. This means that when the sextant is sighted horizotally the arc is symmetrical about the vertical and the instrument is balanced. In a number of earlier versions I have seen the horizon mirror is mounted further from the axis than the telescope. This means that arc extends further forward than backward when held horizontally. This just how it appears in the sculpture and in the picture,

    Robin Stuart

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