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----- Original Message -----
From: "George Huxtable"
>
> This book has been discussed before on this list, starting 3rd May 03,
> thread subject-
> "The Complete On-Board Celestial Navigator Second Edition"
>
> I have a copy of this book. It is good in parts, but VERY bad in others..
>  .....
> Bennett provides a simple way to calculate the azimuth using a lookup
> table

   WRONG ! 4 methods are provided. In order of ascending accuracy they are:

1 Calculated azimuth using the prediction and indentification tables
2 Corrected compass bearing. Accurate enough already for plotting purposes.
3 Azimuth tables - the ones George Huxtable doesn't like.
4 Weir diagrams, the introduction to which reads:
'The accuracy of this method is superior to that of (Azimuth tables)'

The user is urged to become familiar with all methods and to use whichever
seems appropriate. As someone who has used this book extensively I can say
that I have never had a problem with the azimuth tables. I can check the
tables' result with that given by my nav. calculator, accurate to a tenth of
a degree, and if it is out by more than a degree or so I invariably find the
fault has been mine.

The thing to remember is that 'The Complete On-Board Celestial Navigator'
has been designed to be used by navigators of small boats as a practical
tool, rather than by nit-picking academic deskbound navigators. Who are
welcome, of course, to play with it, and find theoretical faults. The author
has a background as a teacher of surveying, so knows all about accuracy.
This book attempts to make celestial navigation more easily feasible
on-board. Don't forget that by the time you work out your fix the boat has
moved on, ultimate accuracy in knowing where you were back then is
irrelevant, since the next thing to do is advance your DR to give yourself a
rough idea of what you really want to know; where you are now!

   

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