'P' is the key

[Loose_Spell_9313]

Of course this is only speculation but I think it is much more likely that the 12 divisions on f67r1 represent 12 divisions of the year, as in 12 months or 12 Zodiac Signs, and not the 12 hours of the half day.  We know the Voynich Manuscript has an interest in at least some of the Zodiac Signs.

I think this is poor logic. I feel that's taking the meaning from one image and ascribing it to all of them. 

There are obviously sequential ones on other folios, almost as if documenting the culture's creation story (in my opinion). This image by itself shows no indication of sequence though. 

I think buying into 'it must be the zodiacs' when no verifiable evidence can ever be proven by that, is simply buying into the mysticism surrounding the manuscript. It being a proto-clock is, by no means, a insane suggestion. 

The first recorded usage of clocks and their mass usage corresponds to roughly this point in history:

[*]You are not allowed to view links. Register or Login to view.: Built a notable, large-scale mechanical clock.
[*]You are not allowed to view links. Register or Login to view.: Created the first portable spring-driven clocks (pocket watches).

This is the time shortly before the release of the Catalan (1375) and the Voynich (~1405-~1430), and the development of clockwork continued onward. The amount of time and knowledge needed to make accurate temporal predictions would have taken exponentially longer than 10-20 years, especially with transportation being what it was at this period. Whatever body of knowledge was the foundation for Vick's clock was based upon years and years and years of data. Otherwise it simply wouldn't have worked operationally and a way that is accurate 700 years later.