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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Geoff Hitchcox
Date: 2024 Jun 12, 17:47 -0700
Adrian_F, there have only been two graphs put forward so far, for a "correction" to apply to the Treworgy Armillary Sundial. I think yours is 'far more correct' than mine (I still can't get my head around the solution ;-)
The only link I could find that has a graph of 'latitude correction' is on Page 10 of this British Sundial Bulletin (PDF doc).
So although one could add a "correction graph" to the Sundial (along with the "Equation of Time" table), could not the Sundial be tipped toward the SOUTH, by adding suitable packing under just three legs - so the Gnomon was now at the correct latitude angle? Although this would now make the HORIZON ring tilted by 7.2753 degrees, the Sundial would give the correct solar time.
Similar to the wedge correction for horizontal sundials, given in this online correction calculator.
Regards, Geoff Hitchcox, Christchurch, New Zealand.
