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    Re: Fix by equal altitude sights around local apparent noon
    From: Paul Hirose
    Date: 2009 Oct 14, 15:54 -0700

    A 1915 article in "Popular Astronomy" described the principle and
    construction of the prismatic astrolabe for observing at a fixed 60°
    altitude.
    
    http://articles.adsabs.harvard.edu/full/1915PA.....23...96B
    
    As far as I've heard, the instrument never caught on with the U.S.
    Coast & Geodetic Survey. They relied on the Bamberg portable transit
    instrument, which observed in the plane of the meridian in the
    conventional manner.
    
    In the "Monthly Notices of the Royal Astronomical Society", Australian
    astronomer W.E. Cooke described an equal altitude method for determining
    latitude and longitude or time by theodolite:
    http://articles.adsabs.harvard.edu/full/1903MNRAS..63..156C
    
    Cooke mentions Chandler's 1887 article on the "almucantar". It's
    online at the ADS site too:
    
    http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?journal=AnHar&year=%3f%3f%3f%3f&volume=..17&letter=.&db_key=AST&page_ind=6&plate_select=NO&data_type=GIF&type=SCREEN_GIF&classic=YES
    
    That peculiar name is what Chandler called his equal altitude
    instrument, which was different from the prismatic astrolabe. It floated
    the telescope on mercury!
    
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