>> I recently gave a similar talk to a client Rotary Club ("All about
Sundials in 15 minutes") and prepared an OHP transparency which shows the
essential relationship between an Equatorial Dial and a Horizontal Dial
but also goes on to show vertical and Polar surfaces arranged around a
common polestyle. It also includes a north-facing Vertical surface. The
original diagram appears in Frank Cousins' book and I have always been
impressed by its ingenious simplicity. My developed version in Adobe
illustrator is in colour and you are welcome to a GIF or PDF copy if you
think it would help.
Just to 'gild the lily' a 3D model was also made which, in conjunction
with a point-source halogen desk lamp, demonstrates the simultaneous
functioning of all four dials 'before your very eyes'. There are JPEGs
available of this from various angles together with a sunlit shot of the
model outdoors.
If 'one picture is worth 10 000 words' then perhaps one working model is
worth many pictures. The only problem which results is that the concepts
involved are immediately obvious to even a non-specialist....which leaves
you very little to actually TALK about ;-)
Copies available to any list member on request. This is the same
material which I offered/distributed some weeks ago.
I retain the copyright of all my images but these can be freely used for
any non-commercial purpose.
Best Wishes
Tony Moss <<
Yes please Tony.
Richard.
E-mail from: Richard Mallett, 14-Jun-2002
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