Rodger, The Madjet is entirely Fred's design. I'm just helping by turning it ito metal.
++ron ----- Original Message ----- From: Roger Bailey <[EMAIL PROTECTED]> To: Dave Bell <[EMAIL PROTECTED]>; John Carmichael <[EMAIL PROTECTED]> Cc: <sundial@rrz.uni-koeln.de> Sent: Wednesday, August 09, 2000 9:56 PM Subject: Re: head nodus > Hi Dave, > > You are correct in your conclusions that analemmatic designs have hour > points rather than hour lines and a universal analemmatic design would > require a series of nested dials. > > Fred Sawyer and Ron Anthony collaborated to produce a beautiful universal > analemmatic design based on this concept. Look for the "NASS Madjet" in the > latest NASS Compendium (7-2). The nested ellipses form a striking design > which they interpret from Egyptian mythology as "Madjet, the papyrus sun > boat on which Ra daily carries the great sun disk across the sky." > > Roger Bailey > Walking Shadow Designs > N 51 W 115 > > > At 12:46 PM 8/9/00 -0700, Dave Bell wrote: > > > > >I may be wrong, and it would be wise to verify this with Fer or someone > >else far more knowledgeable about analemmatic dials, but I see a problem > >with your vision of the dial: > > > >Analemmatic dials, as we have been discussing them, do not have hour > >*lines*. They have hour *points* only, on the periphery of the ellipse. It > >is the "responsibility" of the human gnomon to be tall enough to cast a > >shadow all the way to the points. This sets the scale of the dial > >somewhat, as a truly monumental dial would require Paul Bunyon (or at > >least Wilt Chamberlain) as a gnomon! You can't beat it by - > > > >* Drawing hour lines, from the hour points to the gnomon foot, because the > >foot moves with the time of year. > > > >* Drawing several "nested" dials at different scales (major axis length), > >because the entire dial, including the date line/scale, is proportional to > >the major axis. While you could draw lines connecting the corresponding > >hour points, the central date lines would be of different lengths, so the > >"gnomon" wouldn't have a unique point on which to stand. > > > >This also messes up your thought of painting footprints for different > >height users, because all users, regardless of height, stand on the same > >(date) point. Some just have to extend their arms over their heads, to get > >a long enough shadow. > > > >To some extent, the dial design corrects for the "shortcomings" of the > >users. Note that the date points for Summer are much closer to the North > >rim of the dial, and the hour points for Noon are much closer to the date > >line than 0600 and 1800. These automatically correct for the varying > >shadow lengths per time of day and time of year... > > > >Does this make sense? > > > >Dave Bell > >N37.29W121.97 > > > > > > > > > >
