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    Re: The cocked hat
    From: George Huxtable
    Date: 2004 Apr 5, 07:45 +0100

    When I explained how the effect of anomalous dip could be neutralised by
    making observations around the horizon, followed by-
    
    "This is exactly contrary to Joel's argument, in which he said-
    
    >As everyone knows, the horizon at sea's definition varies with the
    >direction you are >> >looking due to differences in light, sea conditions
    >and cloud cover. Therefore, you
    >have variables with which Greenway is not confronted since his horizon is
    >a constant.
    
    The reasoning I have presented above relies on the SAMENESS of the
    behaviour of the atmosphere in different directions, not on its DIFFERENCE."
    
    I wasn't trying to provoke Joel Jacobs, though it may have read that way.
    If it did (and Joel certainly appears to have been provoked by it), then
    I'm sorry.
    
    Let me express what I was trying to say differently, as follows.
    
    ===================
    
    Joel Jacobs has argued for taking several sights, around the horizon, to
    average out atmospheric variations in different directions. The reasoning
    for averaging out anomalous dip by similar means has a completely contrary
    basis, relying on the SAMENESS of the behaviour of the atmosphere in
    different directions, not on its DIFFERENCE."
    
    ==================
    
    Is that better? We both agree on the value of taking a number of
    star-altitudes, well spread around the horizon.
    
    George.
    
    
    ================================================================
    contact George Huxtable by email at george---.u-net.com, by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ================================================================
    
    
    

       
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