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    Re: Admiral GAGO Coutinho
    From: Douglas Denny
    Date: 2010 Oct 18, 14:43 -0700

    Very interesting. Pity it does not have English sub-titles.

    I have one of these sextants. They are the first successful bubble sextant for aviation use. Basically a marine sextant modified with two standard type of bubble spirit level tubes: one to hold the sextant horizontal laterally, and the other to establish vertical.
    The telescope is a bifocal allowing a view of the normal index and horizon mirrors as normal, and the bubble arrangement at the same time. Hence the telescope views at infinity for index/horizon, and a few cm for the bubble at the same time. Quite simple, but ingenious.
    There is a battery (in the handle) and lamp system to illuminate the bubbles.

    Douglas Denny.
    Chichester. England.
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