Many of you may remember a thread on this list in March of this year
about the "bifilar" name. (I tried to look for it on the AstroArchive
site but I
could not do a search for titles or keywords.  The egroup site is much
better: http://www.egroups.com/group/sundial)

There seems to be continuing concern for the use of this name.  As
before, there seems to be no other reason to refer to these non-linear
gnomons as "bifilar" other than the total lack of any better
terminology!  The new BSS glossary does not even list the term,
"bifilar".

After much consideration, I think a better term would be "bi-gnomon".

This would help relate to the use of "bifilar" which seems to have been
used since 1920 but improve and broaden the definition.  As Chris Lusby
Taylor wrote: 
>Many recent so-called bifilar sundials merely use the 
>intersection of the shadows of two rather arbitrary lines/curves. 

We might use the term "intersecting gnomon" or "bi-style" except that it
seems clumsy.  If we accept the definition of gnomon as any type of
shadow casting object, we have a description of the physical dial.

My thanks to Frans Maes for the posting of more views of the Appingedam
dial and the English translation. He has produced a very richly
illustrated site with valuable references.

Claude Hartman
35N  120W

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