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    Re: Is Sextant an Optical Device?
    From: Dave Weilacher
    Date: 2002 Oct 4, 10:31 -0700

    Well, no.  A horizon isn't a light source.
    
    If you use it to determine distance off from a mountian peak or tall tower,
    those aren't light sources.  I've used mine in a regatta to determine if I was
    gaining or losing on a mast in front of me, not light sources.
    
    
    
    Unless you mean that if you use your eye, it must be optical.
    
    
    
    I'm pretty sure that what it does is measure angles.  Angles that can be
    measured with or without the telescope.
    
    
    
    I guess a car that has more than one rear view mirror is an optical device.
    
    
    
    On Fri, 4 Oct 2002 11:13:34 -0500 Rodney Myrvaagnes 
    wrote:
    
    
    
    > A sextant without telescope measures angles
    
    > between two light sources.
    
    > I don't know what you mean by optics. It isn't
    
    > only lenses.
    
    >
    
    > On Fri, 4 Oct 2002 04:49:13 -0700, David
    
    > Weilacher wrote:
    
    >
    
    > >
    
    > >How about a ruler that has a magnefying bar
    
    > along its length.  It meets all
    
    > >the same criteria for calling it an optical
    
    > device that sextants do.  If your
    
    > >eyesight is good, it works just as well.
    
    > >
    
    >
    
    >
    
    >
    
    > Rodney Myrvaagnes                        J36
    
    > Gjo/a
    
    >
    
    > "If Brecht had directed 'Waiting for Godot,'
    
    > he would have hung a large sign at the back of
    
    > the stage reading 'He's not going to come, you
    
    > know. ' "   -- Terry Eagleton
    
    >
    
    
    
    
    
    Dave Weilacher
    .US Coast Guard licensed captain
    .    #889968
    .ASA certified sailing and celestial
    .    navigation instructor #990800
    .IBM AS400 RPG contract programmer
    
    
    
    
    Dave Weilacher
    .US Coast Guard licensed captain
    .    #889968
    .ASA certified sailing and celestial
    .    navigation instructor #990800
    .IBM AS400 RPG contract programmer
    
    
    

       
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