Anselmo and Others, About analemmatic sundials with correction for EoT you may read articles by Fred Sawyer in: Bulletin of the British Sundial Society, Jun 1994, 94(2):2-6 and Bulletin of the British Sundial Society, Feb 1995, 95(1):39-44.
or an article by me in: bulletin of De Zonnewijzerkring , Febr. 1984. Fred desribes some more solutions as well about the Longwood Gardens dial, I only desribe the latter. The Longwood dial is an aproximation, not fully correct, but acceptable in its reading. The dial has a morning part and an afternoon part, each with its special date scale in the shape of the well known figure 8. Other solutions as mentioned by Fred are fully correct and use the EoT curve at the hourpoints. You may find Fred's articles also on the Repository CD of NASS, ( Sciateric notes ), however not with an example as the Longwood dial. Such an example for London, however, is in the BSS bulletin, Ferbr. 1994. Best wishes, Fer. Fer J. de Vries mailto:[EMAIL PROTECTED] http://www.iae.nl/users/ferdv/ Eindhoven, Netherlands lat. 51:30 N long. 5:30 E ----- Original Message ----- From: "Anselmo PÈrez Serrada" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Tuesday, September 03, 2002 9:32 PM Subject: On analemmatics > Hi John (and the rest of the people)! > > Of course you're right in saying so. The bigger the ellipse, the bigger > the scale of dates... but > maybe they've neglected the (small?) mistake they make... Now the > question is: is this > mistake really neglectable (considering that a person is far from being > a vertical pole, that > his/her feet do not stand at the exact date, and so on...)? Maybe it is > so... But what about the EoT? > > Does anybody in the list know (empirically or theoretically) something > else about this kind > of approximations? > (Fer, Roger, Helmut, Frans Maes, e tutti quanti...) > > Best regards, > > Anselmo > > > - -
