Re: Folio 57v & phebelabia...

[Nick Pelling <incoming@xxxxxxxxxxxxxxxxx>]

Hi everyone,

*Great* point by GC about moon-dials - the 270 degree + 90 degree text 
looks like a superb fit.

In my own attempts to understand f57v, I also did a lot of research into 
volvelles, and moon-dials were structurally the closest fit - but I didn't 
have a secondary reason to back it up, so didn't post.

However, I'm far from certain that this is actually a moon-dial per se. The 
list of characters may correspond to a set of letters, but a numbering 
system? If it's a sequential numbering system, it wouldn't be 
Hebrew/Greek/etc, Latin, Arabic... so what is it?

For instance, it's certainly possible that this is some kind of code-wheel 
*appropriating* the moon-dial use-structure, paralleling Alberti's 
code-wheel - Alberti may not have been the only person who had this idea at 
the time, or perhaps it was produced knowing roughly how Alberti's worked.

An example of what I'm suggesting would be if the first few characters on 
each page indicated a phase of the moon to set this dial to. We're already 
comfortable with the idea (from the low number of copying corrections) that 
the Voynich is a copy of a document - so surely we should be comfortable 
with the idea that this page might be a copy of a volvelle?

I'm not saying it's not a moon-dial, I'm just saying we need to understand 
moon-dials much more before we can make a more solid link between them and 
f57v.

BTW: here's how to make a moon-dial out of paper plates:-

	http://analyzer.depaul.edu/paperplate/Moon%20Finder.htm

Note that the moon-phase (underneath) layer of the paper-plate volvelle has 
four pictures, corresponding to the four phases of the moon - this would be 
a good (structural) match with the four pictures at the heart of f57v.

But the #1 clue might lie in those same four faces - two are turned towards 
us & two are turned away. Perhaps this directly indicates some kind of 
rotational cycle?

Giovanni de Dondi's 14th Century Astrarium had a moon-dial:-

	http://www.geocities.com/CapeCanaveral/Hall/3551/ingle37astrario.htm

And here's an absolutely gorgeous-looking ivory moon-dial (from the 19th 
century, alas):-

	http://www.adlerplanetarium.org/history/exhibits/heavenly/15.htm

Also: note that the correct term for this kind of instrument would appear 
to be a "phebilabe" or "phebelabium", following the examples given by 
Professor David King on this page:-

	http://www.uni-frankfurt.de/fb13/ign/instrument-catalogue.html

This is the same David King who wrote the book "Ciphers, Monks and 
Astrolabes - A Forgotten Number Notation of the Middle Ages", referred to 
on-list not long ago. This number system turned out to have no obvious 
similarities with the VMS - but it was well worth chasing all the same. :-)

I've emailed Professor King to ask if he can direct me to any studies or 
papers on phebilabes - I'll let you know what happens.

Cheers, .....Nick Pelling.....

BTW, my #2 candidate for f57v would be a "Sphere of Life & Death" - at 
David Juste's recent lecture in Cambridge on Early Medieval Medical 
Astrology, he showed a number of acetates of these, showing their general 
form and (semi-random) evolution through the Middle Ages.

What these spheres are: given a certain numerological input (normally based 
on your name and the date of disease onset), they forecast a prognosis. 
Interestingly, the associations between alphabets and numbers that each 
system required to calculate these is a thing that David has studied 
extensively - in his upcoming book, he describes the evolution (largely by 
scribal copying as a form of mutation) that happened to these over a large 
period of time.