The Voynich Ninja

Quote:Early 13th C. in Europe or threabouts, see Fibonacci and Sacrobosco. So that would be OK in the VMS.

Well, what I actually meant by saying that was "zero as a number". I think Sacrobosco just introduced zero as a digit, but did not consider it a number (like one that can be used for numbering objects).

Without getting into the argument of this page, it's worth pointing out that Isa's synodic period theory is a little complex; but that since the time of the ancient Greeks it's been known that the nodal procession of the moon is approx 18 years. This in turn gives us the Saros, an 18 year cycle of lunar eclipses between the sun and moon.