Hello John, I like to give some comments to your message about terms used for sundials.
It is my opinion that to make a classification for sundials is one of the most complecated problems in gnomonics. >From your message I only quote : " * horizontal dials with styles at arbitrary angles (and an inbuilt date scale) are what Gianni calls "mono-filar". This is not too bad a term, but I am looking for an alternative as it implies that the gnomon (and not just the style) is a thread - as it is in the related bifilar dial. Any suggestions?" End quote. The term bifilar sundial is used since its invention early this century. 2 threads are used as shadow casters. We are used to this name for this type of sundial and it is known all around the world. >From this word the term monofilar is derived by Gianni Ferrai because only one thread is used. But this doesn't mean that in these dials it is necessary to use threads. Also edges of a plane may be used. Its edge acts like the original thread. However I hope the term bifilar dial won't disappear and I like the term monofilar dial. As another example also a polestyle can be a thread, a rod or an edge of a plane. I don't know what is the best way to define all these. Best wishes, Fer. Fer J. de Vries [EMAIL PROTECTED] http://www.iae.nl/users/ferdv/ Eindhoven, Netherlands lat. 51:30 N long. 5:30 E
