Hi everyone
Peter what about the The University of Cincinnati's Sundial in
Compendium Volume 2 Number 1 March 1995 Page 8 called the Sun Clock.
The Sun Clock is:
An equatorial ring 16 inch in diameter engraved with an hour circle is
fastened orthogonally to a meridional ring. The assembly is rotated on a
polar axis until the focused image of the sun is centered on the
analemma line. Knowing the season, the month and approximate day can be
read from the analemma scale, and standard time to the nearest minute
from the hour circle. The analemma a graduated scale shaped like a
figure eight that shows the sun's declination and the equation of time
for each day of the year, was skillfully chiseled by hand.
One problem with this sun clock is with vandals they smashed the lens.
Another problem was difficulty encountered in finding a lens with a
focal length of 16 inches that had the desired three eights inch
diameter. The problem was solved by a quick trip to a dime store where a
pair of cheap reading glasses was purchased. By cutting the oversized
glasses under water with a pair of scissors, the innovators fashioned
their lens, which they adeptly fitted into the analemma ring.
One day I would like to make myself a Sun Clock because it has the
equation of time built into it and no chart is required to obtain
standard time. And because it is different to the normal horizontal sun
dial in that you have to move some parts to read it.
Roderick Wall.
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Roderick Wall
E-mail: [EMAIL PROTECTED]
Melbourne Australia.
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