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    Re: Sextant and quintant limits
    From: Richard B. Langley
    Date: 2008 Dec 26, 12:59 -0400

    Quoting "Richard M. Pisko" :
    > On Sat, 20 Dec 2008 12:33:05 -0700, George Huxtable 
    > wrote:
    > >  "Douglas reflecting protractor". (Note, this shouldn't be
    > > confused with the modern Douglas Protractor, a transparent marked-off
    > > square). It was the invention of Sir Charles Douglas, an army man, who
    > > got a
    > > British patent for it (3461 of 1811). I haven't discovered if there's a
    > > way
    > > to access UK patents without visiting the British Library, so if anyone
    > > knows how to do that, that would be of interest.
    > Actually, I believe Sir Howard Douglas, son of Admiral Charles Douglas
    and governor of New Brunswick and founder of the University of New Brunswick!
    > was
    > the inventor.  The oldest hall at the Royal Military College is named
    > after him.
    > At any rate, another interesting reference that *may* be closer to your
    > independent invention is to be found by a Google Book search for
    > "Reflecting Sector" in Philosophical Magazine, of around 1822, pages 301
    > to about 310.  Unfortunately, there are no drawings to correspond with the
    > description of the device by Professor Amici of Modena; but I have seen
    > something that might match in other image searches for "reflecting sector"
    > and "Amici".
    > The device operates over a range of 180 degrees, uses triangular and
    > rectangular prisms; and does sound interesting.
    > Unfortunately, I had to use Internet Explorer to get the pages below;
    > Opera didn't work.
    > Try:
    > --
    > Richard . . .
    > Using Opera 9.2.4 after the "Dog" died
    > >
     Richard B. Langley                            E-mail: lang@unb.ca
     Geodetic Research Laboratory                  Web: http://www.unb.ca/GGE/
     Dept. of Geodesy and Geomatics Engineering    Phone:    +1 506 453-5142
     University of New Brunswick                   Fax:      +1 506 453-4943
     Fredericton, N.B., Canada  E3B 5A3
         Fredericton?  Where's that?  See: http://www.city.fredericton.nb.ca/
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