Hi Frank E,
As Frank K has said, your suggestion for reading azimuths with a polar-oriented
gnomon and a set of declination lines (rather than with a nodus) is perfectly
possible. But, in my experience, it would make the dial somewhere between very
rare and unique as all the English examples I've ever seen make (or made) use
of a nodus. Apart from anything else, trying to read shadows and dec lines on a
wall sundial taxes the eyesight and visual coordination.
FK's wacky idea of a secondary, vertical, gnomon to indicate azimuth directly
is fun. There are cases on horizontal dials (eg the Whitehouse dial in Cumbria)
where this was done. But again, I've never seen it on a vertical.
Any chance of the dial being conserved/restored?
Regards,
John
-----------------------------
Dr J Davis
Flowton Dials
________________________________
From: Frank Evans <[email protected]>
To: "King, Frank" <[email protected]>; "Davis, John"
<[email protected]>; [email protected]; Sundial
<[email protected]>
Sent: Friday, 2 August 2013, 20:36
Subject: Re azimuth lines
Greetings, fellow dialists,
Thanks to all for suggested solutions to my dial puzzle. As I read the dial
picture, the azimuth lines related to the supposed nodus would have extended
from the summer solstice curve, visible on the dial, up to a winter solstice
curve now lost. If so this rules out the use of the figure 8 gnomon support as
a nodus as its shadow in the picture falls outside this frame. Suggestions so
far are that the gnomon is a replacement together with indications of how a new
nodus might be calculated. I am still wondering about the alternative
suggestion I made that there was no nodus but a vertical date scale at the
sides. Then, selecting the date, you follow the declinational curve from there
to the point where the gnomon shadow crosses the azimuth line and that gives
the sun's bearing.
Is this correct in principle and do any dials anywhere use this method?
Frank 55N 1 W
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