Hi Again: Just to see what would happen, using Rogers new and improved analemmatic DC macro drawings, I noted the average midway Bailey point positions on the major axises for many analemmatic sundials between the latitudes of 15 and 55 degrees and found out that for all these latitudes the Bailey Point is exactly where the November 1 blue date line intersects the major axis! (North of about 60 degrees this isn't so, however)
This means that you can easily figure out the position of the Bailey Point of any analemmatic if you just know the azimuth of the setting or rising sun on November 1. A line drawn from Nov 1 on the central date line in this direction will cross the major axis at the Bailey Point. John John L. Carmichael Jr. Sundial Sculptures 925 E. Foothills Dr. Tucson Arizona 85718 USA Tel: 520-696-1709 Email: [EMAIL PROTECTED] Website: <http://www.sundialsculptures.com> ----- Original Message ----- From: "John Carmichael" <[EMAIL PROTECTED]> To: "Sundial List" <[email protected]> Sent: Wednesday, November 13, 2002 6:24 AM Subject: Bailey Point Determination > Hi Analemmatic dial aficionados: > > If you look closely at an analemmatic dial face drawing I made from Roger > Bailey's new Delta Cad Macro for Banff Canada, you can see that the blue > sunrise and sunset lines intersect the major axis line in the same general > area but not exactly at the same point. (see PDF attachment). > > There is not really a Bailey Point but a Bailey Zone. But for practical > purposes, it is convenient to think of this as a single point. > > On the Picture Rock table analemmatic, I considered the Bailey Point to be > where the Solstice lines intersect the major axis. But you can see from > close inspection of the drawing that it would be more precise to use a point > that is midway between the solstice line intersection and the Oct-1 line > intersection. > > Does this seem like a good way to determine the "average" Bailey Point > location? > > John > > John L. Carmichael Jr. > Sundial Sculptures > 925 E. Foothills Dr. > Tucson Arizona 85718 > USA > > Tel: 520-696-1709 > Email: [EMAIL PROTECTED] > Website: <http://www.sundialsculptures.com> > -
