Hi Duane: Another way to incorporate the equation of time into a sundial is to use the "analemma" - a graphic representation of the EofT - placed on a pivoting surface with a gnomon/sight to produce a shadow or solar image on the analemmic surface - the pivot is scaled relative to a fixed, marked surface to show the time in standard hours/mins. during daylight. This is generally known as a heliochronometer - you can see the ones I make at http://atensundials.com . I like this design because it is simple and one design works at any longitude and latitudes between 20 and 50 degrees North or South without much loss of accuracy at the extreme ranges.
Cheers! Dave G.
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