Hello Bill, ( and others ) Thanks for your suggestion to use a cord to find the correct intersection point between a date line and the shadow line in an azimuthal dial.
Although my program Spin is restricted to latitudes outside the tropics I calculated such a dial for latitude 0 degrees and for suntime. The picture is attached to this mail. It is clear that this dial can't be used during several weeks around the equinoxes. At the equinoxes the time can't be read at all. At that time, half a day the sun is due east and then jumps to due west for the rest of the day. Fer J. de Vries [EMAIL PROTECTED] http://www.iae.nl/users/ferdv/ Eindhoven, Netherlands lat. 51:30 N long. 5:30 E ----- Original Message ----- From: Wm. S. Maddux <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Cc: Mac Oglesby <[EMAIL PROTECTED]>; SUNDIAL <[email protected]>; Fer J. de Vries <[EMAIL PROTECTED]> Sent: Friday, January 21, 2000 4:40 PM Subject: Re: Azimuthal dial snip..... Fer, please forgive my tampering with your SPIN.GIF, in order to illustrate this suggestion. Bill Attachment converted: Macintosh HD:spin0.gif (TIFF/JVWR) (0000C6FC)
