WAXSing and waning (2)

In September 2022, Liberato de Caro and his team published a follow-up to his previous papers (reviewed in the previous post, WAXSing and waning), called ‘Long-Term Temperature Effects on the Natural Linen Aging of the Turin Shroud,’ in an MDPI journal called Information. Starting with their previous conclusion, that the Shroud has suffered similar deterioration as a textile from Masada, but understanding that each textile’s different history renders a simple one-to-one correspondence unreasonable, they have constructed various possible routes through time and geography, and determined that an itinerary of Jerusalem (c.30 years) > Beirut (c.900 years) > Constantinople (c.200 years) > Lirey (c.250 years) > Chambéry (c.125 years) > Turin (c.440 years) seems to fit the data best. The other routes considered time spent in Edessa, Memphis or Camulia as possible alternatives to Beirut on its way from Jerusalem to Constantinople, but these were found less probable. The authors admit to possible variation in the Constantinople and Lirey periods, as it is not known when the Shroud left the one or arrived in the other, nor what happened to it in between. It is assumed that it left Constantinople in or after 1204, and arrived in Lirey in or before 1354. However they do not consider the possible variations of conditions and/or movements during the 900 years or so before the cloth arrived in Constantinople.

Justifying their conclusions involves detailed data bases of the annual variations in temperature and humidity at each of the stopping points. Clearly, since well over half the time was spent in one of the four alternative ‘first stops after Jerusalem,’ conditions there were the most influential, and the Shroud’s short stays in any possible intermediate destinations, such as Greece, Malta, Belgium or southern Italy had a rather negligible effect. Also, the famous fire of 1532 is considered to have had a negligible effect, as the accelerating effect of the high temperature is thought to have been exactly countered by the decelerating effect of the low humidity.

The long-term sojourn possibilities were, from hottest to coldest: Memphis – c.22°; Beirut – c.19°; Edessa – c.18°, Camulia – c.10°, and from wettest to driest: Beirut – c.66%; Camulia – c.55%, Memphis – c.51%, Edessa – c.49%. From this information, and using the timescale above, a value called CBnor could be calculated, using the equation:

CBnor is the number of ‘chain breaks’ in the cellulose of the sample, divided by a ‘maximum’ number derived previously, giving a fraction of between 0 (modern) and 1 (ancient). The Shroud, after all this calculation, achieved a CBnor of about 0.6, which by coincidence is, we are informed, quite similar to that of Masada, but very different from that of a medieval European cloth, which is about 0.05.

It all looks very impressive, but I’m afraid lacks sufficient control for any of it to be at all convincing. In my previous post I commented on the unreliability of the samples chosen for testing, and the lack of appropriate controls. De Caro’s previous two papers on the subject determined the age of samples from different ages (although notably none between 1000AD and modern) experimentally, and derived a value from their findings called the Aging Factor, which can be converted into an Aging Parameter, and thence to a CBnor for any time during the history of the textile.

Table 1 of ‘X-ray Dating of Ancient Linen Fabrics’ gives the Aging Factors of several samples:

In ‘X-ray Dating of a Turin Shroud’s Linen Sample,’ the Shroud sample (TS) was tested in a similar way and determined to have an Aging Factor of 10.0.

From this, Aging Parameters (AP) for these textiles can be derived using:
AP = (AF – AF(min)) / (AF(max) – AF(min))
where AF(min) is the AF of a modern textile, and AF(max) is the AF of textiles so old that they all have the same AF regardless of age. From the table, AF(min) is 7.56 and AF(max) is 11.6,

The AP ranges from 0 (modern) to 1 (ancient) as follows:
B: 0.0
A: 0.1
DII: 0.2
D: 0.4
TS: 0.6
FII: 0.7
NII: 1.0
E: 1.0
HII: 1.0
LII: 1.0

The AP is the same as the CBnor of the textile today, when the experiments were carried out, derived from experiment. However the CBnor can also be calculated theoretically, given the age of the material, the temperature and the humidity of its environment. If the temperature and humidity vary, then successive applications of the long equation above will enable the CBnor to be calculated.

The four graphs below show the calculated CBnor for the Shroud, given estimates of the environmental conditions at the various places it might have stayed. The thickening of the lines to towards the top right demonstrates the uncertainty of when the Shroud moved from Constantinople to France. (Je, Me, Co, etc. represent the places in which the Shroud may have stayed)

The only one that matches the experimental CBnor of the Shroud suggests the 900 year period was spent in Beirut.

So far, so good, but it is a pity that none of the other textiles were subject to the same treatment, to find out if the assumptions and equations used for the Shroud are really meaningful. For instance, the average temperature and humidity of Masada are 22.6°C and 59.5% (from https://tcktcktck.org/israel/golan-heights/masada). This is hotter and damper than Memphis (22.1°C and 51% according to de Caro). If we take the portion of the Shroud graph relating to Memphis and extrapolate it as if it had remained there rather than moving north, we should be able to discover an appropriate minimum CBnor for a Masada textile (which from experiment was 0.7).

This is clearly nonsensical, as are the similar results for all the other textiles sampled. Jericho, for instance has an average temperature and humidity of 16.0°C and 58.6% (from https://tcktcktck.org/israel/golan-heights/masada). This is not unlike the conditions in Beirut. If the portion of the Shroud graph relating to Beirut is both extrapolated and given an origin of 1000AD, which is when the Beirut textile originated, we get:

This too makes no sense at all.

This is enough to demonstrate that in spite of the apparent sense of all the considerations and equations discussed by de Caro and his fellow authors, nothing of value can be derived from them.

Furthermore, if the proportion of ‘chain-breaks’ in the cellulose of linen is controlled entirely by temperature, humidity and time, and nothing else, then it should not be necessary to be quite so careful in the selection of threads and fibres as was the case here. The samples for these WAXS experiments were taken from a selection originally listed in Giulio Fanti’s papers on the dating of textiles by the mechanical strength of their fibres. For that, it was necessary to select fibres which, in his opinion, had not been subject to mechanical weakening, so that only their age was the contributing factor, but in this case, a much wider selection could have been made, including linen from, say, Peru, which Fanti entirely rejected in his previous paper, medieval Europe, which was never considered, or for that matter Japan or Canada. Only using textiles from burials in Middle Eastern tombs, even if from different eras, is too narrow a field for a fair comparison with medieval linen.

We also note, as I did previously, that the sample tested in this case came from the radiocarbon corner, which very few authenticists consider to be representative of the Shroud anyway. Joe Marino thinks it is mostly composed of 16th century interpolation, Ray Rogers found it heavily contaminated with gum and dye, and Robert Rucker thinks the whole Shroud has been bombarded with subatomic particles, which must surely have caused a few extra cellulose chain-breaks of their own.