The Voynich Ninja

Full Version: Assumptions baked into the VMS carbon dating
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(30-08-2026, 10:30 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.No objections to that for the Balneo section.  But is there any plausible Taccola influence on Astro/Cosmo, which contains f68?
Yes, the foldout VM f70r2 vs. Taccola's star-sun with face and pipes from You are not allowed to view links. Register or Login to view.

[attachment=17493]
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(30-08-2026, 10:30 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.Anyway, given that the vellum of f68 looks like an off-cut, it would not be unlikely that it was left in a "rejects" box in the corner of a scriptorium or someone's attic for a century or more.  Vellum is not perishable and does not change appreciably in that time scale.
I remember the assumption (from Lisa ?) That the ink was applied on relatively fresh parchment, but I don't know what this claim is based on. I wouldn't rule out old parchment but I don't know about the effects of age on ink or color retention.

(30-08-2026, 08:05 AM)eggyk Wrote: You are not allowed to view links. Register or Login to view.Why is it less likely that someone would source the same quality parchment years later?
Because I would assume bad parchment contains more information which varies by creation process than high-quality parchment which is just uniform. Meaning 2 sources of bad parchment should exhibit larger differences that 2 sources of perfect parchment. But that's just my assumption. Clearly I would not rule anything out, including self-made parchment. I think a lot can be learned from both the creation process of parchment and examining the parchment of the VM. Lisa said the VM exhibits heavy wear which may have smoothed out differences between parchment batches. But again, this is something experts on the matter should take a look at. There's not much we can infer from the scan.

(30-08-2026, 08:05 AM)eggyk Wrote: You are not allowed to view links. Register or Login to view.A long while ago I downloaded a similar software to the one mentioned in the report (or a newer version, maybe), and using the most modern curve available through the software at the time (maybe 2020?) I believe the results looked much the same. But i'm not professionally trained to use the software, and I may have made a mistake somewhere. It may be valuable to check, though!
Thanks! I wouldn't expect dramatic differences but it would be interesting if the time-windows and probabilities slightly shhift with a newer curve. I know nothing about C14 dating outside of an university lecture many years ago but I do know the matter is far from trivial and a lot of errors can be made in both sample treatment and  calibration. You'd want to use IntCal20 with no reservoir correction. I don't think any correction have to be applied for parchment.nd pipes
(30-08-2026, 09:04 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.[..] Vellum is a non-perishable commodity, like timber, leather, copper, or vitriol, so a merchant's stock could well have new vellum mixed with decades-old vellum.  Especially considering that the Author was happy to take off-cuts and grossly defective sheets. 

There is no reason to believe that a medieval merchant stocked those „long-lasting“ vellum batches for decades, even exceeding his own lifespan.
This would have been dead capital, even more when this vellum is endangered by parasites, humidity and decay. Argument of defective/low-quality material is even worse: no tradesman would keep such product for 20 or even more years in his books and shelves.
As long as there is not one example of such „business practice“, I can‘t assume the story of „VMS was written very much later, on then older vellum“.
(30-08-2026, 09:04 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.Again, why?  Even if the Author acquired that bifolio in the same buying/begging/stealing/rummaging transaction as the other folios, it does not follow that they were all manufactured at about the same time.   Vellum is a non-perishable commodity, like timber, leather, copper, or vitriol, so a merchant's stock could well have new vellum mixed with decades-old vellum.  Especially considering that the Author was happy to take off-cuts and grossly defective sheets.  Are you perchance assuming that the Author made the vellum himself?

No, my interpretation would apply to any situation when you take 4 random samples from any large collection of fungible (not unique) manufactured items bundled together in the past. Would similarly apply to a bunch of timber blocks or undated copper coins. If three items are found to be definitely from 1390-1460 and also have a large common range of 1404-1450 and the fourth item by measurement alone is 50% 1310-1350 and 50% 1390-1438, I would say it's extremely more likely that the fourth item is from 1390-1438 and it's quite likely that the whole bundle is from 1404-1438, just the by way human society works. It's possible and likely that a pile of rocks in the forest have completely unrelated timelines each. For human manufactured and human consumed items the general rule is that if something can be used, it will be used, if something can be sold, it will be sold, and if something stays neglected for a long time, there is a reason for this too (missing owner, lost or forgotten items belonging to the same owner ). Human manufactured fungible items are produced by someone who wanted either to use or to sell them, and each person buying them likely had intention to use or resell them. Making no assumptions about the manuscript and the parchment, just the fact of it being a bunch of goods bundled together, affects the probability of a common time and place of origin significantly, compared to items randomly sampled from different places.

The above only applies to fungible items. Obviously, this doesn't works for collectibles, but I don't think raw parchment of low quality is a collectible in any sense.

(30-08-2026, 09:04 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.But in this case that single-interval summary would be rather uninformative, even misleading, because the distribution has two well-separated humps with non-trivial areas.  Thus a better summary is to split the gray distribution into two curves and find the 68.2% or 95.4% intervals R,S for each hump.  The areas of the humps for the f68 sample seems to be about 0.445 and 0.555. Then we can say that the date is within the R interval with 0.445 x 0.954 probability and within the S interval with 0.555 x 0.954 probability.

Thank you for the explanation, I think I understand how the values were computed, but I'm still not sure what these numbers imply for the probability for the item to be from the first range or the second.

To make it simple, consider the graph below. The yellow bar is the distribution of measured samples, to greatly simplify computations let's assume it's uniform between the min and the max values. If I understand the computation above, in this particular case the probability distribution would simply be the shapes A and B and the probabilities would be proportional to the areas of A and B, is this correct? The areas are comparable, I'd even say A is a bit larger than B, so the percentages are roughly equal and range a gets a bit more than 50%.

However, if we look at the distribution of the measured samples (yellow band), we find that most of them cannot be produced from range a at all. Shape A only reaches up about 20-25% into the sample distribution, so then we will have to understand how 75+% of the registered samples were produced? 

In this case I can imagine, the more correct metric of the probabilities of range a vs range b would be which part of the sample range is covered by each period, so, for range a it's c / (c + d), which produces a small number like ~18%.

I suppose the difference lies in the question being asked, but I'm not sure I understand what the question is in either case.

[attachment=17494]
(30-08-2026, 12:21 PM)Bernd Wrote: You are not allowed to view links. Register or Login to view.
(30-08-2026, 10:30 AM)Jorge_Stolfi Wrote: You are not allowed to view links. Register or Login to view.No objections to that for the Balneo section.  But is there any plausible Taccola influence on Astro/Cosmo, which contains f68?
Yes,  the foldout VM f70r2 vs. Taccola's star-sun with face and pipes from You are not allowed to view links. Register or Login to view.
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Indeed, if Taccola was a source for Bio, it would be a plausible source for the sun image in that diagram as well. 

It would be another case of the Artist misinterpreting what he was copying.  The 8-lobed blue star has been described as a "flower".  But the "nervures" on the "petals" now suggest that it could be a crown of rays, like in the Taccola drawing.

However, I don't think that Taccola was the first "artist" in many centuries to think of depicting a sun with a face and a halo of rays like that. So it is possible that both figures were copied from earlier originals.  

Note that the VMS version has a crown of "flames" around the face, some of which extend into the "pipes"; and it also has "pipes" extending from the tips of the "petals", as well as from the gaps between them.  Did the Artist provide those details on his own? Or was he copying from some other figure?

Quote:I remember the assumption (from Lisa ?) That the ink was applied on relatively fresh parchment, but I don't know what this claim is based on. I wouldn't rule out old parchment but I don't know about the effects of age on ink or color retention.

I don't recall any such statements, and it seems highly unlikely.  At a minimum, a few months must have elapsed between the vellum being made and the Author acquiring it.  The scribing of the whole VMS must have taken many more months.   So "fresh" would have been several months at least.  Would there be a noticeable difference between writing on 6-months-old vellum and 60-years-old one?

And I don't see what physical-chemical process could allow one to determine that detail by looking at a 600-year-old manuscript.  

Quote:
(30-08-2026, 08:05 AM)eggyk Wrote: You are not allowed to view links. Register or Login to view.Why is it less likely that someone would source the same quality parchment years later?
Because I would assume bad parchment contains more information which varies by creation process than high-quality parchment which is just uniform. Meaning 2 sources of bad parchment should exhibit larger differences that 2 sources of perfect parchment.
AFAIK the vellum-making process was quite standard, because consumers and dealers must have wanted minimally consistent quality across manufacturers. A 400 page manuscript has 100 bifolios; it seems very unlikely that one would be able to source them all from the same maker.  

On the other hand, the VMS folios are all of bad quality, but are all different in size, edge finish, holes, creases, even surface finish. I bet that each bifolio could have been made in a different year and a different town in Europe -- and we would not be able to tell that now.

All the best, --stolfi
(30-08-2026, 12:34 PM)Stefan Wirtz_2 Wrote: You are not allowed to view links. Register or Login to view.There is no reason to believe that a medieval merchant stocked those „long-lasting“ vellum batches for decades, even exceeding his own lifespan. This would have been dead capital.

Compare that to the lumber or leather trade.  A merchant would normally keep a stock of hundreds of whole skins and/or pre-cut sheets of each quality and size.  When he sold or bought another batch of some type, he would not have to follow a strict FIFO policy; he might as well randomly mix the new and old sheets.  So the sheets in each stock pile could end up having vastly different ages. The old ones would not be any more "dead capital" than the new ones; they would be just "capital".

Quote:Argument of defective/low-quality material is even worse: no tradesman would keep such product for 20 or even more years in his books and shelves
Like for timber or leather, there would be a market for off-cuts and "reject-quality" vellum: for small-format booklets, for stuff that had to be permanent and waterproof but did not have to look good, for scribal practice, for covers and binding strips, ...

Merchants and manufacturers may or may not have stored off-cuts and "reject-quality" material.  Merchants may have acquired whole skins, cut them into standard-size sheets, and kept the off-cuts and bad pieces for when and if someone (like an old impoverished trader returning from China) wanted to buy them.  Throwing those pieces away would still be throwing money away.  Vellum sheets, good or bad, may have gone through several wholesale and retail merchants before reaching the final consumers.

Quote:even more when this vellum is endangered by parasites, humidity and decay.

But the big attraction of vellum was that, like leather, it was resistant to those threats.  The tanning process made it generally indigestible by insects and unaffected by humidity.  

The worm holes that we see in the VMS seem to be all on places where water spills could have softened the glue from the covers and transferred some to the adjacent vellum sheets.  Unlike the vellum itself, typical glues (hide glue, gum arabic, library paste) are edible.

All the best, --stolfi
From the voynich.nu:
The probability distributions of the four measurements are shown together in Figure 2 below:
[attachment=17495]
This shows in a very visual, yet qualitative way that the four measurements are consistent. There is no indication that the samples represent a different age.
...
The dating of each folio doesn't allow a very precise dating of the MS. The uncertainty in age for each folio is some 50-60 years, and in the case of fol.68 even spans two centuries due to the above-mentioned inversions of the calibration curve. / ... / Since they are likely to be from different animals hides, these are indeed independent observations. Combining these observations leads to a combined un-calibrated age of 1434 plus or minus 18 years (1 sigma). The corresponding 14C fraction is 0.9379 plus or minus 0.0021 (1 sigma). Applying the calibration curve to these values leads to the following combined age probability distribution for the Voynich MS:
[attachment=17496]
The 95% probability interval lies between 1404 and 1438.

The analysis of the Vinland map is then described, and the situation is different — the consistency is not the same as with VMS, even though the samples were taken from the same sheet, but there were differences in the degree of purification.
As I understand it, the estimate of 1404–1438 may not be entirely accurate, but it is nevertheless justified and based on an analysis of certain errors.
Various sources and various uses of the "golden ray" technique.

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(30-08-2026, 06:21 PM)R. Sale Wrote: You are not allowed to view links. Register or Login to view.Various sources and various uses of the "golden ray" technique.

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Thanks!  To my eyes, the one from that lot that most resembles the Taccola halo around the Sun is 

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Namely, the lengths of the rays in the halo of Jesus are not random.  The envelope of the rays is almost (but not quite) a fat star.

All the best, --stolfi
(30-08-2026, 06:08 PM)ololololo Wrote: You are not allowed to view links. Register or Login to view.From the voynich.nu:
The probability distributions of the four measurements are shown together in Figure 2 below: This shows in a very visual, yet qualitative way that the four measurements are consistent. There is no indication that the samples represent a different age.
Well, I disagree.  

Based on that data, it is still possible that all the four bifolios have the same C14/C12 ratio.  But it is more likely that the ratio for bifolio f67+f68 is significantly lower than the ratios of f26+f31 and f42+f47, while that of f1+f8 is a bit higher.  Again, there is no reason to assume a priori that the four bifolios all have the same ratio.

Moreover, showing the probability distributions of the C14/C12 ratio is misleading, because the same value of that ratio can correspond to very different dates. One should look at the probability distributions of the calibrated dates.  And these show that there is ~40% probability that the vellum of bifolio f67+f68 is ~75 years older than the others.

All the best, --stolfi
According to the university, the C14 concentration rises slightly following solar flares.
These are said to have a cycle of approximately 11 years.
Is this even measurable in parchment, and would it make any difference?
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