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    Re: Classification of the methods for clearing the Lunar Distances
    From: Fred Hebard
    Date: 2003 Apr 10, 20:20 -0400

    Bruce,
    
    Perhaps my summary of Bowditch was inaccurate rather than the work
    itself.
    
    It said:
    
    "Davis' Requisite Tables, published in London in 1905, introduced the
    cosine-haversine FORMULA [emphasis mine] to navigation, although it had
    been used previously by astronomers.  This formula is
    
    hav(z) = hav(L~d) + cos(L)cos(d)hav(t),
    
    in which z is zenith distance (90-h).  This is sometimes written
    
    hav(z) = hav(L~d) + hav(theta),
    
    in which hav(theta) = cos(L)cos(d)hav(t)."
    
    
    A few pages earlier, Bowditch mentions that, "Early tables for
    solutions of meridian angle were called horary tables."
    
    I must add, in the same spirit as Herbert Prinz, that I much admire
    your work.
    
    Fred
    
    
    

       
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