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    Re: Daytime Venus Rising Dip Short
    From: Robert Eno
    Date: 2012 May 6, 10:52 -0400

    From what I understand, two vertical wires are all that is needed because
    with a spherical bubble chamber, a slight fore and aft tilting of the
    sextant has no appreciable effect on the accuracy of the sight. A lateral
    (side to side) tilt does have significant negative consequences in the
    accuracy of the sight.
    
    I can support this contention based on my own observations taken with my
    MkIXA sextants and with the pre-1970's era C.Plath bubble attachment
    (notwithstanding that the C.Plath has both vertical and horizontal wire).
    
    I have had the pleasure of using a Kollsman Periscopic sextant in a C-130.
    Let's just say it is not as easy as it looks!
    
    Robert
    
    ----- Original Message -----
    From: "Alexandre E Eremenko" 
    To: 
    Sent: Sunday, May 06, 2012 10:08 AM
    Subject: [NavList] Re: Daytime Venus Rising Dip Short
    
    
    >
    > Gary,
    >
    >> They are only in the Kollsman instruments.
    >
    > In MkIXA as well. Two vertical wires helping you to keep the
    > bubble near the center.
    >
    >
    > Alex.
    >
    >
    >
    >
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    > The message was checked by ESET Smart Security.
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    > http://www.eset.com
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    >
    
    
    __________ Information from ESET Smart Security, version of virus signature 
    database 7113 (20120505) __________
    
    The message was checked by ESET Smart Security.
    
    http://www.eset.com
    
    
    
    
    

       
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