Edley, Steve, Andrew, et al,
Approximate 'trig.' from memory is all very well, but
why not simple geometry of equality and bisection?
With a string, twig, or weed-stem part as arbitrary
unit-length b, swing a circular arc. Cut successive
chords of length b, which if connected to the center
Re ceiling dials,
Lets get empirical:
I. Take a piece of ordinary looking glass and hold it by
its lateral edges, close to and beneath, your eye, and
look at some test grid (e.g. the day squares on a
calendar) across the room. Compare the appearance of
the squares' lines by low-incidence
Fred,
A place to start should be:
www.monticello.org/press/sundial.html
Best,
Bill Maddux
Received the following today. Can anyone help Scott Vincent? Reply to
[EMAIL PROTECTED]
--
Dear Mr. Sawyer:
Can you direct me to the artisan who reproduced
Willy, Frans, et.al.,
Willy suggested:
... Photograph a drawing of a vertical sundial
and compare the drawing with the corrected photo.
.
Might I suggest a test photo of a Cartesian grid
(or a checkers-, or chess-, board? The analysis
would then be simpler and more generalized.
Also,
Hello John,
You wrote re E.O.T. sign conventions:
I don't think we will ever convince everyone to
adopt a single convention. Even if we did, we
are stuck with a wide historical literature
which is fairly evenly split between the two
possibilities.
I think that about sums up the E.O.T.
