>Return-Path: <[EMAIL PROTECTED]> >Date: Fri, 24 May 96 17:23:18 GMT >From: Les Cowley <[EMAIL PROTECTED]> >Subject: RE: Ceiling dials >To: [email protected] > >Gorden Watson wrote: >>I am interested in making a ceiling dial - >>a mirror on the window sill reflecting >>the sun's image onto the ceiling. >> >>Has anyone a) done this, or b) know where >>I might get some "designs". > >There are instructions in Chapter 14 (pp 116- 121) of Waugh's book "Sundials - Their theory and construction", Dover 1973. He describes mirror placement and how to lay out or calculate the hour lines on the ceiling. > >Are there additional books and sources that members recommend on sundial design and calculation? I have recently subscribed to the list - sorry if this is a FAQ. >
I know the theory of this construction, wrote in two old Italian books: "Perspectiva Horaria sive de horographia" (in latin), by Emanuel Maignan, ROME 1648, and "Epitome Gnomonica" (fouth part), by Cesare Scaletti, Bologna 1702. But if you prefer an interesting matematical explanation you can find it (in Italian language)in an article by Giuseppe Zuccalà in the "ATTI del V° seminario nazionale di gnomonica", San Feliciano 1993. Maybe you can obtain that publication calling at the e-mail address: [EMAIL PROTECTED] bye Mario Arnaldi ====================== MARIO ARNALDI Viale Leonardo, 82 48020 Lido Adriano RA ITALY [EMAIL PROTECTED] ----------------------
