"T.& M. Taudin-Chabot" wrote: > ... > >Another way to solve the gnomon height problem might be to make the inner > >ring the June ring, when the sun is highest and the shadow the shortest. The > >next ring would be July followed by May, August, April, Sept, March, Oct, > >Feb, Nov, Jan, and December as the outer ring. This ring order would place > >those summer short shadow months closest to the gnomon and the winter long > >shadow months further out. This ring arrangement would increase the number > >of hours where the shadow crosses the date lines and make the dial more > >functional. > > How about making concentric rings for each declination, the innermost for > +23.44 and the outermost for -23.44
I'm afraid that doesn't help, as the whole idea was to have only one (wiggly) line for each hour. The arrangement you propose gives you the conventional figure-of-eight hour lines. Another approach would be to have a ring for each value of the EoT. That turns the figure-of-eight hour lines into a figure-of-infinity date line. Having found today's date one follows the ring it's on to read the mean time directly from the shadow. This should be easy to use. The hour lines could be almost straight. Chris Lusby Taylor Newbury, England 51.3N 1.4W (where I'm far enough from the equator not to be worried by gnomon height!)
