Wednesday, May 20, 2015

Where does blood fit into the new two-stage medieval forgery model of the Turin Shroud?

First, here's a commercial for my other specialist Shroud site. I have changed the banner. The previous one showed steps in a one-step thermal imprinting ("scorch") model- from template to negative image to tone-reversed positive to the final 3D-enhanced image. There wasn't space to do all of that with the new model. It simply shows key steps leading up  to the primary negative image, and even then there's only space to show half the final imaged hand (my own).

New banner on my shroudofturinwithoutallthehype website. Click to enlarge.

However, rest assured that the image produced with the two step procedure (imprinting with flour/water, then developing the image with nitric acid) does respond reasonably well to Secondo Pia style tone-reversal (negative to positive) and to 3D  rendering in ImageJ (see previous posting).

Some have noted that I've said little about bloodstains in the new model. I don't intend to, considering that blood (or should that be "blood", i.e. some kind of blood substitute?) while showing some curious and perhaps unexplained details is not one of the 'enigmatic' features of the Turin Shroud, the latter being confined to the faint body image. (It cannot be said too often that the so-called "wounds" and "injuries" on the TS are NOT visible in the body image per se, but merely INFERRED from the locations of bloodstains. What's more, that's true also for the dumbbell-shaped imprints of many of the scourge marks: they are imprints made by trace amounts of blood only. They lack scientific corroboration and thus verification in the body image as regards proving authenticity. (But then, this blogger's aim is not, and never has been, to disprove authenticity - merely to pour cold water on the daft claims - from self-styled "scientists" no less - that the TS body image could never have been generated except by supernatural means).

What any model has to explain is why there is no body image under bloodstains, at least according to the crucial test that Adler and Heller did with their protein-digesting enzyme under the microscope. (One would have preferred more direct evidence that the blood is underneath, not on top of body image - the latter being a more convenient geometry from a forger's point of view- but let's take that particular  Adler/Heller result at face value, even if remaining unwilling to do so in respect of all their results - notably their scarcely-credible  "bilirubin story").

The new model accommodates the 'blood-first, image second' chronology.  One applies the imprinting medium first to the human subject, then, before it's had time to dry, one paints or dribbles on the blood. One then imprints onto linen. The blood is the first of the two liquids to make contact with linen, so there will be no body image under blood. Indeed body image will end up on top of blood.

But is that scenario necessarily the one that was deployed, with its rather demanding time-frame, inasmuch as blood, with all those intricate patterns, has to be applied before the imprinting paste dries and becomes useless for imprinting? Answer: NO. In fact, it's through a consideration of the practical constraints on a 'conjoint' imprinting of blood and body image that some tantalizing alternative scenarios suggest themselves. They will now be briefly flagged up.

In fact, let's cut to the chase with the new thinking. Here goes. The Turin Shroud was not intended originally to be a blood AND body imprint forgery, only a blood one. In other words, it was intended originally to be a whole-body counterpart of the Sudarium of Oviedo, the latter being the alleged face-cloth that was applied to the face of Jesus immediately after death on the cross, with bloodstains but NO body image.

How might that blood-only imprint have been obtained? Answer: by applying blood to a live volunteer (or corpse) in all the biblically-correct locations for scourge marks, crown of thorns, nails in hands and feet, lance wound in side, then taking a double (frontal v dorsal) imprint onto linen.

Map of locations of 372 scourge marks according to Faccini and Fanti*
 *Link to their pdf

 Straightaway one sees a rationale for scourge mark 'over-kill' (there being allegedly 372 of them): without that multitude of scourge marks that cover most of the naked body from chest and shoulders to foot, there would be large empty areas on the imprint.

From a posting this blogger did some 3 years* ago, showing how scourge marks on the Shroud respond to 3D-enhancement in ImageJ, despite being blood-only (not body image)
 * Link to June 2012 posting

One also has a rationale for the absence of loin cloth, otherwise problematical in terms of artistic sensibilities. Folded hands over groin area AND a multitude of scourge marks across bare buttocks helped ameliorate that problem.

A Mark 1 (blood only) length of linen could have been conceptualized, and indeed promoted, as the actual one that was used to transport the crucified Jesus from  cross to nearby rock tomb by Joseph of Arimathea (not intended as final burial shroud note). For all one knows, that blood-only forgery might have been stored for a period, weeks, months, maybe longer,  giving blood plenty of time to set hard and oxidize. Might a new idea have entered the heads of our forgers. Why stop there? Why not call the volunteer back for a second imprinting on top of the blood of something that could be claimed to be body image, created by drying  and yellowing of ancient SWEAT?

How practical is that one may ask: to imprint with "sweat" in a second entirely independent session introduced as an afterthought? Answer: probably not too difficult. Why not? Because the task of correctly aligning blood-stained linen over a flour-pasted body would be much simplified by the fact that the initial blood penetrates the weave of the linen to give a reverse side imprint. That reverse-side blood can then be used to assist with alignment. By the same token, some small discrepancies are likely, as indeed is the case with the TS. Was that blood from a nail wound really mean to be in the wrist (which while mechanically-correct had not featured previously in Western art)? Was there really supposed to be blood trails in the hair, a dubious feature, given blood from scalp wounds tends to clog and create matted hair, not run in rivulets)? Was the blood initially applied to the cheek of the volunteer? Are blood and bosy images out of 'stereo-register', as pro-authenticists have claimed to counter criticism of unrealistic blood trails down hair. Or are these the clues to separate imprinting of blood and body image - in that order?

Is there hard evidence for the Mark 1/Mark 2 chronology suggested, with an indeterminate gap separating the application of blood then body image? Answer: no, and probably never will be, short of discovering some  forger's diary that had slipped down the back of a well-preserved medieval sofa.
Bloodstains - back of head - one of 20 raised-contrast images from my 'Shroud Scope'  gallery*

*Link to gallery, June 2012

But there's one feature that supports it: that's the 'messiness' of some of the bloodstains, notably on the back of the head, that one infers as being due to the crown of thorns. There is something uncompromisingly 'messy Sudarium of Oviedo-like' in that blood, in sharp contrast to the neater (some might say too neat) scourge mark imprints and blood trails on forearms etc. Indeed one even wonders whether the blood stains evolved in separate instalments, say the major ones first, followed by the more subtle and mannered scourge marks later, all this happening before there was an intention or even inspiration to overlay them all with a body image.

Time now to take a break and deliberate further on this more nuanced scenario - a phased evolution of the Turin Shroud, starting initially as big blood-brother to the Sudarium of Oviedo.

Update, May 22:  here's the opening to a comment on the shroudstory site from the tedious Charles Freeman, self-styled historian (writer of history-themed books actually - something entirely different):

"Disproving my hypothesis that the Shroud was originally a painted linen with iconography of the fourteenth century whose pigments have disintegrated would be a step forward. It has not yet been done so I am keeping the hypothesis alive." 

This is not how science operates. It's not even how academic research in any discipline operates. One does not propose a hypothesis, especially one that ignores or flies in the face of accumulated data, and then sit around, waiting for others to disprove one's hypothesis.

To be useful a hypothesis has to be framed in terms that make it testable. To constantly intone, as Freeman does, that there are experts in painted linen out there who given the right equipment will one day prove him correct, is the ANTITHESIS of academic scholarship. (Yes, "experts in painted linen": how's that for begging the question?). The man is a crushing bore, and vain and arrogant with it too. It's time his publishers took a long hard look at the lack of solid scholarship. He is NOT an academic historian.

It's about as exciting a spectacle as watching a circus tightrope performer with a safety net.  Freeman's safety net is his entirely imaginary community of painted linen experts that he sees as his insurance policy should the going become too difficult.

Update: Saturday May 23

Some comments from David Beltz (posting as daveB) of Wellington, NZ have appeared recently on the shroudstory site, one where I no longer place comments (those who follow that site can probably guess why). However, it shan't prevent me from responding to them here.

Here's the first, reproduced in full, with a par-for-the-course put-down reference to this blogger/retired biomedical scientist highlighted in red.

daveb of wellington nz
May 21, 2015 at 6:30 pm
The difficulties are many. A primary difficulty is one of access. The custodians discharge their duty conscientiously over what many regard as a sacred relic. Even the scientists seem too narrowly focused. There are narrow sectional interests. The big advantage of STURP was that it was multi-disciplinary and they were all able to work together. We have not seen its like in sindonist studies since. There seems to be a difficulty with regional and national horizons. The Americans who contributed so hugely to our present scientific understanding seem to have been locked out by the Italians, who seem to have their own peculiar perspectives.

Large-scale funding is required if the investigations are to be anything other than amateur. Much of the science too seldom seems to get as far as the peer-review stage. Colin Berry labours on in his kitchen or his garage, but his work seems to be too agenda driven.
On the historical front, too much has already been lost. The historians find much to criticise in what meagre documentation there is, and they even complain at intelligent speculation, calling it writing a novel.
The ancients were capable of a great deal more than they are generally credited with. As a young man, I found Sprague de Camp’s history on the ancient engineers most enlightening. Given their industry and individual innovation, I do not find it surprising that they might be capable of weaving a herring bone cloth of the dimensions of the Shroud, regardless of what looms might or might not have been generally available at the time.
I see no future in the painted linen hypothesis, only that it may be disproved. No ancient or medieval painting has the realistic form of the man on the Shroud. Shred the paint off any portrait on linen. If anything remains, it will still look like only an artifact by human hand.
In the meanwhile, the Shroud can serve its purpose as an object of religious meditation, which in these pages is too seldom considered.

So I'm an amateur now, am I, despite a record of published research, some highly cited, and despite having supervised and/or examined PhD theses, acted as referee for top biochemical/biomedical journals? One loses one's professional credentials on retirement - is that the take-away message. Oh, and there's that reference to me continuing to labour away in my kitchen and garage. First, our sniffy and superior David Beltz seems to have overlooked that I have ceased labouring away, having proposed a generic two-stage model for the TS that involves first stage imprinting followed by second stage colour development. The model has been validated using white flour for Stage 1 imprinting followed by nitric acid vapour or solution for second stage colour development. No, I'm not "labouring away" David Beltz. I am awaiting critical comment, though none has so far emerged, folk like you much preferring to make derisive putdowns. As for the kitchen and garage: to the best of my knowledge, nitric acid behaves exactly the same inside a glass jar or bottle in my garage as it does in the laboratory. I could if I so desired impose on a close relative who does biomedical research in one of the world's most prestigious research laboratories, said to have a "Nobel Prize winner on each floor" that is  just a 40 minute drive away, and repeat my experiments there, thus avoiding references to my garage completely. However, I respect that individual too much to do that purely to impress the smug superior David Beltzes of this world.

I'll be back later with another comment from the Mr.High and Mighty David Belz later in the day, one that places another now deceased home-researcher, STURP's Raymond N.Rogers up on his customary pedestal. We'll take a look at what Mr. Rogers is quoted as saying in that 'peer-reviewed' paper of his re the alleged detection of starch on the Shroud, by someone else, not he, himself, and the allusions to Pliny era spinning and weaving technology, and proceed to ask: who's the one making rash, unsubstantiated claims and assumptions, and who's the one trying to stick to the facts, backed up by patient and careful experimentation, albeit in a kitchen or garage?

Oh, and as for that reference to my research being "agenda driven", I've stated repeatedly that my beef is with pseudoscience that masquerades as science. If that's an "agenda" so be it, but I suspect that folk were intended to place a rather different construction on Mr.Beltz's deployment of that term, which from where I am standing is about as mean and despicable an implication as one can get, though entirely predictable where that increasingly no-holds-barred  pro-authenticity cheer-leading, tub-thumping shroudstory site is concerned.

Oh, and here's one from the same incomparable daveb made at the start of the month :

daveb of wellington nz
May 2, 2015 at 7:34 pm

Colin has now been attempting to reproduce the properties of the image for some three years, with indifferent success only, although I applaud his perseverance. Might we suppose that a less chemistry-informed artisan would have struck it lucky any sooner? As one early commentator observed, Colin is more likely to end up proving the resurrection from all his efforts.
So it's a race is it to the correct answer? Who are the other competitors may one ask in the modelling department? Who are these "less chemistry-informed artisans" who should have crossed the finishing line ahead of me?

What we see here, yet again, is snide, belittling comment, the bane of internet forums, that can be summed -up in a single word: TOXIC!

There have been hints previously of that engineer's antipathy towards science and scientists. Here's just one example that I saved to file a way back:

daveb of wellington nz
January 25, 2014 at 3:45 am | #168
The sampling area is clearly anomalous, and unrepresentative of the whole, never mind the details. No other area was sampled. To assert the truth of an hypothesis on such ambiguous evidence would never be accepted in any other scientific endeavour. It merely demonstrates wishful thinking on the part of skeptics and anti-authenticists, not to say their poverty of scientific reasoning. Precisely the same poverty of thought that Yves Delage encountered from the Science Academy in 1905, dominated as it was then by so-called free-thinkers and agnostics. Some things never change!

And he has the nerve to accuse me of being 'agenda -driven' ! This from the same man that faltly rejects the d'Arcis memorandum in its entirety, on the grounds that the original Latin document was uncovered and translated into French in the late 19th century by Ulysses Chevalier, who he claims was ideologically tainted and, guess what, agenda-driven?  The ease with which our David Belz resorts to genteel smear tactics doth truly take the breath away.

And here is another gem from our all-knowing, all-seeing commentator. It's supposed to be authoritative science (peer-reviewed journal!!) from Ray Rogers no less.

daveb of wellington nz
May 22, 2015 at 9:48 pm
(MAILLARD REACTION) MAY EXPLAIN THE IMAGE FORMATION” Raymond N. Rogers & Anna Arnoldi, 2003, This article originally appeared in Melanoidins vol. 4, Ames J.M. ed., Office for Official Publications of the European Communities, Luxembourg, 2003, pp.106-113.

“Observations of weave density and lignin content of the shroud fibres (Rogers, 2001) indicate a very mild bleaching technique in agreement with the methods described by Pliny the Elder (77). The same technology was in use, with some minor differences, until after the last crusade in 1291 (Hochberg, 1980). Linen was spun by hand on a spindle whorl. When the spindle was full, the spinner made a hank of thread. Each hank of thread was bleached separately, and each was a little different. Different parts of the same thread in the shroud’s weave show slightly different colours, like a variegated yarn. The warp thread was protected with starch during the weaving process, making the cloth stiff. The final cloth was washed in a solution made from Saponaria officinalis. Saponaria produces four glycosidic saponins, and all hydrolyse to produce sugar chains. (Ya Chirva et al., 1969) The following carbohydrates were identified in those chains: galactose, glucose, arabinose, xylose, fucose, rhamnose, and glucuronic acid.”

“The presence of starch, in particular amilose, on the shroud was confirmed by the fact that during testing for sulfoproteins in blood areas with an iodine-azide reagent (which bubbles vigorously when sulfur is present), a reddish background was formed. Image colour does not appear under the bloodstains when they are removed with a proteolytic enzyme. Whatever process produced the image, colour must have occurred after the blood flowed onto (or was painted onto) the cloth, and the image-producing process did not destroy the blood (Heller and Adler, 1981).”

Note that the authors are asserting that several carbohydrates, including some sugars, were identified, and also amilose, which I take to be a starch. Authors also cite Heller & Adler regarding blood-stains. Searching on “starch” on web-site results in several other papers.

My response:

Had the paper come to me for refereeing with that cited passage above, it would have been rejected out of hand.

I'd have appended the following specific comments to the author and journal Editor:

1. Do not go citing Pliny the Elder out of the blue, begging the question re Shroud authenticity, implying that the radiocarbon dating can be safely ignored.  Oh no it cannot. The author might think it invalid, based on his examination of a few threads illicitly removed from the radiocarbon sample, with a subsequent gap in the chain of custody. But he cannot expect others to take his rejection as the consensus position in science. It's not. Indeed, the manner in which Pliny has been insinuated into the above text suggests strongly that Raymond N.Rogers was not strictly neutral and disinterested on the subject of authenticity when he penned the above paper, making it worryingly possible that he was not  neutral at the time he worked with STURP in 1978. It's my belief that Rogers was a closet authenticist. If he considered the radiocarbon dating was hopelessly wrong (by some 1300 years!)  then he as STURP's chemical team leader should have been the one to press for a repeat dating - not to go tacitly assuming authenticity. Science has to be totally objective in its written PEER-REVIEWED publications.

2. The presence of starch "confirmed" with a reagent that designed to test for something entirely different? The correct reagent for detecting starch is a solution of iodine in potassium iodide, which gives a blue-black inky colour with starch. A solution of iodine in the presence of sodium azide, intended to detect sulphoproteins, one that gives a totally different colour (red), CANNOT be assumed to be testing for starch or one its 2 components UNLESS VALIDATING TESTS ARE REPORTED.  They were not. We are asked to accept that iodine/azide is a dual purpose reagent. Who says? Neither does it inspire confidence to see a reference to "amilose", it being AMYLOSE needless to say. Secondly the differentiation between amylose (straight chain starch) and the unmentioned amylopectin (branched chain starch) simply cannot be inserted into a scientific account without a word of explanation. In any case, the two components of starch were not properly recognized as distinct chemical entities until the 1940s. Their relevance to colorimetric tests for starch is highly questionable to say the least, unless dealing with genetic variants of wheat and other cereals, notably maize, that are enriched in one or the other (e.g. waxy maize starches that are almost entirely amylopectin, which gives a red or purple colour with iodine/potassium iodide). What we see here is at best sloppy and imprecise unscientific reporting that should never have got past the referees.

3. There is no conclusive evidence that starch or other polysaccharides and/or sugars are  present on the Shroud, and even if the red colour with iodine/azide were admissible evidence, for which no assurance is offered, the evidence for that was from Adler and Heller. One CANNOT GO BASING MAJOR CLAIMS (as Roger's "starch fraction/Maillard hypothesis" has become a major claim) on evidence from other workers, in other laboratories, that is little more than anecdotal.

Repeat: the paper that David Beltz cites as if the gold standard in Shroudology SHOULD NEVER HAVE BEEN ACCEPTED FOR PUBLICATION.

Research note: while considering my own intervention in TS image research to be largely complete (it is sufficient in science to produce a feasible model that may be beyond the resources of oneself to test ) I may place an order for some iodine/potassium iodide ("Lugol's") solution as a test for starch. The model proposed predicts that while the flour-derived starch would still be present immediately after development with nitric acid vapour (possibly not with the acid as solution)  the starch granules would then selectively wash out in the neutralization step with sodium bicarbonate (leaving just the yellow or orange  nitrated wheat gluten). While starch granules are not 'soluble' in cold water or aqueous solutions, they are nevertheless easily washed out by mechanical action, being of microscopic dimensions, which is the basis for separating wheat gluten protein from starch by kneading flour dough under water, washing out the starch, leaving a rubbery mass of gluten.

I shall add a photo here later of wheat starch granules that I isolated by the washing procedure when showing that it is protein, not starch, that is responsible for the yellow coloration formed when nitric acid reacts with a flour imprint on linen.

 Here are those photos (late addition):

Here's the dried-out sedimented starch at the bottom of the container, after kneading a flour dough so as to be left holding a rubbery mass of gluten (protein)in one's palm. The millions of tiny starch granules then settle out under gravity.
Here's the same sedimented starch, after breaking up into chunks. It's almost but not quite protein-free. Starch granules contain traces of protein (the so-called starch-granule proteins like friablin etc) that are important in determining milling quality - "hard" and "soft". This starch contributes next to nothing to the yellow or orange colour image seen when the negative flour imprints are developed with nitric acid. The colour is due to reaction between nitric acid and gluten proteins.

Update/progress report:  Sunday 24 May

The two stage image capture/image development  model proposed here, which to the best of my knowledge has never been articulated previously, far less demonstrated experimentally, could be said to have began life on 1st April this year (not the most auspicious date I grant you). It was the final posting and abandonment of sulphuric acid as hypothesized agent for the yellow-brown TS image, that acid having been found wanting (it can discolor linen, but only at high concentration AND elevated temperature).  That was the signal to look at alternative acids, with nitric acid being the obvious candidate. The next posting laid the historical groundwork, describing how nitric acid was known in the 13th/14th century, thanks to the writings of 'Pseudo-Geber', possibly one and the same as the Franciscan monk-cum-alchemist, one Paul of Taranto.

Here's a list of the postings on this site, since April Fool's day, taken from the summary table provided by Blogger Blogspot (which hosts this blog) and the current total of visits/views for each posting.

1 April 15 (125 views)

6 April 15  (89 views)

6 April 15 (157 views)

9 April 15 (292 views)

20 April 15 (56 views)

21 April 15 (168 views)

3 May 15 (109 views)

6 May 15 (72 views)

20 May 15 (92 views)

That's a total of 1160  views since April 1, starting with that abandonment of the briefly-scrutinized H2SO4 model, and subsequent switch to oxidizing/nitrating HNO3.

Typical response  (with one or two welcome exceptions) from commenters on Dan Porter's shroudstory site :

"If you and your model were any good, you’d have thought of it sooner, instead of wasting our time these last 3 years with your blather"

In addition, there are these 2 recent postings on my specialist Shroud site, only recently reactivated after being dormant since end-2014:

13 May 15 (16 views)

Modelling the Turin Shroud: forged in the 14th century as a white flour imprint onto linen? Then chemically developed with nitric acid to resemble ancient yellowed sweat?

19 May 15 (8 views)

A generic model for how the Turin Shroud could have been forged via a TWO STEP process (image capture, then separate image development).

However, the true birth date for the current hypothesis, and the break with previous "thermal scorch" thinking , could be said to have been with this one on Feb 28, 2013

Shroudie-Alert: Day 11 Emeritus Pope Benedict XVI – what is one to make of his devotion to the Shroud (despite that radiocarbon dating)?

 The title, with its reference to the present Pope's predecessor,  provides no clue. But it's the posting in which a careful note was taken of the recent discovery at Machy, close to Lirey, of a mould for a second Lirey pilgrim's badge, with the inclusion of that (arguably) Veronica like face of Jesus above the word SUAIRE. That was when the thought first occurred to this blogger/retired biomedical researcher that the TS body image was meant to be seen as a sweat inprint. How might an ancient  (1300 year old) sweat imprint be - or have been- created as a negative imprint on linen? It took a while for strong mineral acids to be considered, despite one of them (H2SO4) getting a brief mention in STURP's 1981 Summary, as an agent capable in principle of discoloring linen to produce a tan image. But who's watching the clock - or calendar? I'm not. We are, after all, discussing what is said to be the most studied artefact in human history. What's a few months, or even years more? The important thing is to find the model that best fits all the known facts, one that can be used to make predictions capable of being tested, were the TS ever to be made available for a STURP Mark 2 study. Make up of that new team? I'd suggest that it be international, but restricted to folk who have made original and significant discoveries in their field of relevant expertise unrelated to Shroud studies. (This researcher considers he would qualify on account of his discoveries relating to photochemistry of bilirubin,  membrane effects on hepatic glucuronidation in the endoplasmic reticulum and (especially) much-cited work on the preparation, physicochemical and physiological properties of resistant starch as an essentially  man-made form of dietary fibre).

Wednesday, May 6, 2015

The chemical principles behind the iconic Turin Shroud can now be explained. All that remains is to produce a look-alike copy.

Important update (13 May): for a 16 point summary of the new nitric acid model, see the new posting on my specialist Shroud site.
It's said that a picture is worth a thousand words. Here's a flour/egg yolk imprint done just two hours ago, photographed here after removal from the nitric acid bath, neutralized with bicarbonate, rinsed with water, shown here drying on the radiator, ready for processing in Image J (tone reversal as per Secondo Pia followed by 3D rendering).

Here's the above after further processing (click to enlarge).  Top left: the dried image after ironing flat. Bottom left: conversion to B/W, then a Secondo Pia style tone-reversal. Right: the secondary B/W image after 3D rendering (Image J).

It's taken over 3 years of almost non-stop experimentation, but this blogger/retired science bod is now able to explain how the faint negative image of the Turin Shroud was obtained (as a feat of medieval technology, aided by alchemists).

The task: produce a contact image that could be claimed to be that left by the crucified Jesus on Joseph of Arimathea's 'fine linen'.

It's incredibly simple in principle (why didn't I think of it sooner?):

1. Paint an adult human male (alive or dead) with an organic paste or slurry as imprinting medium (in other words, turn them into a giant rubber stamp). My preferred medium right now is a dispersion of white flour in cold water, but that could change).

2. Press linen against the subject (or subject against linen) to leave a moist imprint. Dry.

3. Develop the image chemically using a suitable reagent , one that converts the organic material to tan (yellow-brown) oxidation products (less probably Maillard reaction products).

My preferred reagent right now is nitric acid vapour, the means of production were known to medieval alchemists (notable "Pseudo-Geber" who may have been one and the same as an obscure Franciscan monk known as 'Paul of Taranto'

4. The yellow-brown aka sepia  imprint will be a 'negative' of the subject, inasmuch as the light/dark tones one sees in photograph are reversed. In other words, the highest relief  (nose, chin, forehead etc) will be dark, not light, and the lowest relief (eye hollows etc) will be light, not dark. They are light in a photograph as a result of reflecting most light. In an imprint, they are darkest through making best contact with a surface.

So I maintain that the plausible science is established - at least in principle-  so far as producing a negative  sepia 2D image from imprinting off a 3D subject is concerned.  Whether it matches all the additional or peculiar characteristics of the TS image (extreme superficiality, lack of reverse side image, lack of uv fluorescence, microscopic characteristics etc.) remains to be seen. However, let's insert a note of caution: not all those listed characteristics were necessarily there immediately after image formation, regardless of age - centuries or millennia. Some of those characteristics may be a result of ageing. At present it seems sensible to adopt a broad-brush approach, attempting to accommodate  only those 'headline' characteristics of the TS that have led to its being described as iconic or enigmatic. Where the latter are concerned, the prize for the most 'iconic' must surely go to the pioneering 1898 photography by Secondo Pia, which converted the Shroud negative back into a positive (by innocently treating the TS as a positive and convereting to a negative!).

It is the conversion one sees above that led to what must surely be the sound conclusion that that the TS negative image must be an imprint, probably a contact-imprint, one that on tone reversal allows one to see the 'real life' (or death!) appearance of the imprinted subject. It's for this reason alone that the dismissal by Charles Freeman of the TS as 'just another medieval painting' that has simply (and conveniently) lost its pigment over the centuries is so hopelessly blind to the implications of the negative image and Secondo Pia's spectacular discovery.

It's not sufficient, needless to say, to establish a scientific framework. There has to be a sizeable input of technology too. While history provided one or two pointers to the likely science (alchemy etc) there is no such  assistance where attempts are made to deduce the technology employed, i.e. applying the science in the manner that achieves the best end result. One does not even know for certain what the desired end-result was, or for what purpose, though I've believed it to be an attempt to simulate an ancient sweat imprint, ever since spotting that Veil of Veronica-like motif labelled SUAIRE on the Machy Mould for a Mark 2 (or Mark 1) Lirey Pilgrim's badge.  (It was that discovery more than anything that decided this researcher to abandon the idea that the TS was a thermal scorch, designed perhaps to symbolize the slow-roasting of the Templar leaders in 1314 for alleged heresy and other indiscretions. That seemed plausible given that one Geoffroi de Charney died alongside Jacques de Molay (Grand Master), de Charney being thought by genealogist Noel Currer-Briggs to have been uncle to his near-namesake, Geoffroi de Charny, Lord of Lirey, first recorded owner of the Shroud in western Europe).

So the working hypothesis IS that the TS is a simulated sweat imprint, that an imprinting procedure using an organic material was devised, probably with input from an alchemist, to develop the imprint chemically so as to produce a more intense, more easily visible yellow or yellow-brown colour. What we see now may of course be a pale shadow of the original, given centuries of fading, image fibre attrition etc.  But there's an upside to that: one does not need to be too concerned about one's pilot techniques producing images more prominent and/or well-defined than those on the Shroud.

After preliminary and somewhat unsatisfactory attempts to image from first  my hand (reasonable result) and then my own face (the less said the better - see preceding posting) I decided to use up-and-over imaging of the toes on one foot. The scale is handy for the size of my jars with the wide necks and ground-glass stoppers for nitric acid vapour. One can compare LUWU and LOTTO imprinting in the same experiment (which may or may not be relevant to the imprinting of the real Shroud). LUWU = Linen Underneath With Underlay; LOTTO = Linen On TOP, With Overlay).

I'll conclude this verbiage with photographs of results with this new tootsie test system as they come. Here's are some photographed just an hour or so ago. More will follow later. There are no plans to write any new postings until the current round of technology-testing is complete. Whole face imaging has been shelved for now. (Maybe Luigi Garlaschelli was right - a bas relief was needed for the face).

Imprint of toes onto linen (left) versus cotton (right). Imprinting medium: white flour/cold water only.

As above, after use of autocorrect in MS Office Picture Manager.

The lower half is a classical "footprint" obtained using LUWU configuration. The upper half is an imprint of the tops of toes obtained by turning the linen up and over, and gently pressing (LOTTO configuration).

More pictures to come (testing of egg tempera as imprinting medium etc).

Yes, egg tempera was the vehicle used as vehicle for paint pigments in medieval  times before the appearance of oil paint in the Renaissance. Despite being primarily egg yolk egg tempera not only attaches well to surfaces but is surprisingly durable. If searching blind for technology that might have been used to add flesh, so to speak, to the fundamental science, it would be unwise to ignore so common a commodity as tempera. In fact, there's one compelling reason for thinking why it may have been used, if only as part of a mix of ingredients: if the aim was to simulate a sweat imprint, it helps to have a visible yellow imprint before the chemical development (or indeed as a Mark 1 undeveloped imprint) given its yellow colour.

Here's the result of imprinting onto linen with a mix of flour, egg yolk and a little milk as extender.


Here's a comparison of three imprinting media:left- flour ; centre: egg yolk; right: flour + egg yolk. All had a little extra milk as extender (having been added to egg yolk to bump up the volume I decided the others should have it too).

Note the poor imprint on this occasion from flour "only". Well, as stated, is wasn't flour only. It was flour with a little milk. An immediate difference was noted compared with flour without milk - there was much less adhesion to the skin, much less force needed to pull the linen away from the skin.

The adhesion effect has been commented on earlier, with the observation that adhesion helps produce an instant high-fidelity imprint. That's due to the amazing ability of flour paste or slurry to stick onto so many different surfaces (this blogger has a photo album he made as a small child in which flour was used as an austerity-era paste - most  of the photos are still where they were stuck). A reasonable working hypothesis might be that milk has weakened the adhesive power of the flour. Good or bad thing? At first sight bad, because it means less flour attaches to the linen (probably) giving a weaker imprint. But might there be an upside? Possibly, as will be discussed shortly.

Yes, one encounters something quite unexpected when imprinting with flour paste. The linen quickly absorbs the liquid when pressed against the skin, such that the latter seems almost dry when the linen is peeled off. That makes for a good imprint, obviously, with so much flour transferred from skin to linen. But there's a possible downside. If transfer is complete, or nearly so at all contact sites, regardless of applied pressure, angle of contact etc, then how can the image be expected to show the 3D properties of the TS image. For 3D properties there needs to be some systematic factor at work such that variations in relief (height above a reference plane obviously, but maybe more subtle factors too) are captured in an analogue process to give variations in image intensity and subsequent 'apparent 3D' properties. That cannot happen if the medium transfer is too efficient at all points. So it may be necessary to include an additive, one that our medieval artisan might have included if only to make the adhesion weaker (he would not have been worrying about final 3D properties!).

Reverse-side imaging?  Yes, there's some at present, as the next pictures will show. But a medieval forger would probably not have wanted it either, if it gave the slightest clues to how an image was faked. This is where technology as distinct from science needs to be harnessed: finding simple ways of reducing or eliminating reverse-side imaging in the proposed flour/water model.

Here are some thoughts for a model system that focuses specifically on  efficacy of medium transfer as a function of 3D relief:

I would use the knuckles of my clenched fist as the 3D subject I'd paint the knuckles with various imprinting media (flour +/- milk +/- egg yolk etc) that had been coloured up with some ink or pigment, then press into fabric (probably re-using linen from previous experiments). The aim would be to find  a mix where the knuckles were imprinted more prominently than the rest of the fist, through having the highest relief. It would probably need to be a stiffish mix, whatever the ingredients, so as to avoid the mix being squeezed off the extremity down into the furrows between knuckles - not what one wants when trying to capture 3D relief!

Update Thursday 19:14

The footprint (mine!) top left was imprinted onto linen using a mix of white flour, egg tempera and a little milk. The image has been tone-reversed in ImageJ (bottom left).  The latter has then be 3D rendered (right).

The initial imaging was performed by standing on one foot, with a view to getting the best impression, but that was maybe not a good idea in retrospect: pressure would have forced the imprinting medium off the highest relief, eg the flat of the toes, resulting in less-than-satisfactory 3D-imaging.

Friday May 8

Here's the result of my fist-imprinting experiment. The result was disappointing, as will be seen, probably through an inappropriate choice of imprinting configuration (LUWU instead of LOTTO) that will not be repeated.  Iwill show it, however, and for 2 reasons. First, this is a real-time account of a research project, warts 'n' all. Second, as is so often the case in reseacrh, while an experiment may fail in its primary purpose, it can lead to unexpected and interesting side-observations. There was not just one, but two of those in the "Fist 1" so I'll now provide an, er, blow-by-blow account.


Here's the consistency of the highest of 5 concentrations of flour/water dispersion tested.

Paint fist.


Press fist into strip of linen, starting at the far left.


Here's the imprint on the linen.


Now add a measured volume of water to the flour/water mix with stirring to make it less viscous.


Now repaint the fist with the runnier mix.

Repeat the process of diluting and re-imprinting 3 more times, working left to right along the strip.

Here's the final strip, with its 5 scarcely visible flour imprints. They will first be left to dry on radiator, and the linen then sewn to make a flat hoop, imprint on outside, to be suspended in nitric acid vapour over conc. nitric acid solution.

Here's the strip inside the 'developing tank', with a glass plate over the top. The clothes pegs were intended to keep the linen clear of the liquid acid.

In fact, one single linen thread had dangled down into the acid, drawing the latter up by capillary action.  A quick rep-adjustment put a stop to that, but the instant image development in the wet area gave an idea for another experiment, results of which will follow this one. The idea: to compare nitric acid vapour versus liquid solution as a developing agent.

Here was the linen after image development in nitric acid vapour, with the 5 fist imprints going from left to right.

Here's the same, with added yellow lines to act as dividers.

And here's the reverse side of the linen, with very little 'reverse-side image' - confirming that flour/water is a good imprinting medium in principle, despite there being much R&D still needed to produce a TS-like image.


While the method works reasonably well for flat(tish)parts of the anatomy (see earlier results with the back of my hand, sole of foot) it does not like complex relief (face, clenched fist).

So those imprints above of my clenched fist are maybe difficult to recognize as such. But as hinted at earlier, it was a mistake  to have adopted the LUWU mode of imprinting. I had thought that passive pressure would give the simplest most recognizable imprint, but that was not to be, probably due to the right-angle turn at the knuckles , but other factors too, like excessive give in the underlay, and a possible rocking action. Never mind: the experiment yielded useful data in other respects as regards the possibility of using solution as a fast-acting alternative to vapour, and the virtual absence of reverse-side imaging.

The experiment also got me thinking about engineering the 'ideal' imprinting medium likely to yield the best 3D result.

The ideal mix will probably still flour as a major ingredient (large intact endosperm cells help reduce penetration and reverse-side imaging).  It will perhaps have egg tempera too, if only for its yellow colour, making it easy to know where to paint blood stains on top of body image. But it has (probably) to be paint-like in consistency and covering power, attaching first to skin, whether unwashed, with skin oils present, or washed (leaving unobstructed keratin, i.e. protein), but then transferring cleanly onto linen. There is now work to be done in identifying that mix, while at the same time maintaining credibility re the options that would have been considered in a medieval workshop.

Comparing nitric acid vapour and liquid solution as image developing agents

I reverted to LOTTO mode for this test. First paint back of hand with flour slurry (no additives).

Here again is that amazing 'cling film look one gets when placing linen on top, then pressing gently.

Here's the negative imprint - scarcely visible.

Now turn the imprint into a simple jigsaw puzzle. 2 pieces will developed in HNO3 vapour, two in conc HNO3 solution (70%).

Here I am adding the acid to one of those two pieces. Image development is seen almost immediately.

Here we are a few minutes later, with image development without noticeable leaching of colour, or migration from image to non-image areas. Success!

Here's the downside of using solution. There's a lot more acid that has to be neutralized before the linen can be removed for drying, ironing and photography.

here are the 4 developed pieces re-assembled. The image of the back of my hand is complete. There seems to be no reasons for thinking that vapour is superior to solution or vice-versa, at least where image-development is concerned.

And as before, there is scarcely any reverse-side coloration.

Next question: does one need concentrated nitric acid for development, if used as liquid? Might a lower concentration work too, albeit more slowly, but without the same degree of hazard?

Some quickie tests are in order, making serial dilutions of the conc acid, e.g. 70%, 35%, 17.5%, 8.75%  for a quick idea.

Come to think of it, use of nitric acid solution raises new technological possibilities. Let's suppose that the essential ingredient of the imprinting medium - provisionally white flour - is fixed instantly to the linen. But suppose there were additives in the medium that gave it a more functional paint-like consistency that were undesirable as left-overs in the final image. What is they were not fixed by the acid?  Maybe they could leach out into the liquid acid (not possible if vapour used), so that one was left with the just the chemical constituents needed for the 'right' kind of image.

Results: testing nitric acid solution as  developer, with a range of concentrations:

First, a paintbrush loaded with white flour dispersion was used to make a trellis pattern on linen. After drying squares were cut out for immersion in different concentrations of nitric acid solution.

Here are the squares in pots with the indicated concentrations of nitric acid (w/v). This was after about 30 minutes of contact. Pronounced orange colour has developed not only at the top concentration (70%), but at half that (35%) and half that again (17.5%). Only at the lowest concentration tested (8.75%) was there no unequivocal colour development.

Here are the same samples after 1 hour in acid, neutralization with sodium bicarbonate and partial drying on a towel.

Conclusion: the model works with nitric acid solution as well as vapour. What's more it's not necessary to use concentrated nitric acid (gives off fumes, hazardous).  It works well (and fast) with nitric acid diluted with water to 4 times its initial volume, i.e. to 8.75%, which  at approx. 2.75M is only a little higher than the concentration of bench dilute nitric acid (generally 2M).

Imaging of forefinger using the new quickie liquid developer (nitric acid SOLUTION) to compare different imprinting media.

Here's the final 3d-rendered image (posted first to allow transfer to shroudstory as progress updateI.

The stages in obtaining that image will be added later.

May 8, 19:12

The above 3D image was obtained while the test linen was still wet and drying on the radiator. (Man in a hurry).

The sample has now fdired and been pressed with a steam iron. Here are the definitive pictures:

The as-is imprints, after development in nitric acid solution.

As above, after tone reversal in ImageJ.  (A Secondo Pia transformation of a negative imprint back to a positive - or at least a pseudo-positive).

As above, after 3D rendering in ImageJ.

Now, back to the start:

Ready to start imprinting: flour slurry in the pie pot, egg yolk in the glass, and a 50/50 mix of the two in the egg cup.

After imprinting, drying on a radiator before chemical development. Note however the almost photograph like character of the egg yolk imprints, especially on the left. There's absolutely no reason why medieval folk should not have seen that kind of realistic imprint, albeit as a negative image. All that was need to produce trhe TS was to think up a way of fixing that egg yolk (or similar) image to make it permanent, maybe with some colour reinforcement.

And here's the new simplified image development step - simply immersing in nitric acid solution, 10% w/v and upwards. The lower end of the range is recommended to reduce fumes.

Update Saturday May 9

Feedback from Dan Porter's shroud story site (from Thibault Heimburger MD) and my response:

May 8, 2015 at 4:52 pm
I have to admit that Colin’s work is very interesting.
In fact, it is the best work (still in progress) I ever seen, based on the “chemical imprint” hypothesis.
The fact is that the TS image is an “imprint”, not a paint, is obvious.
The fact that the TS image is a contact-only imprint rather than a contact+non-contact imprint is still undecidable.
Hopefully, at the end, we will see if the best contact-only hypothesis (the “chemical imprint”) can match or not at least the macro properties of the TS image.
Colin wrote (see his blog): “The task: produce a contact image that could be claimed to be that left by the crucified Jesus on Joseph of Arimathea’s ‘fine linen’.
Not only that.
The TS IS such an image. But this image has some fundamental properties.
So, we will see.
Sincerely, good luck.
May 9, 2015 at 12:07 am
Thanks Thibault. Your comment is most gratifying, and shows true generosity of spirit, given our differences in the past.
In an earlier comment here yesterday, I was deliberating on what should be the ideal consistency of the imprinting medium in order to achieve best 3D effects. I said it should be paint-like, i.e. tacky and viscous, so as to stay where applied on the 3D subject, since if runny, it would flow off the highest points of the relief down into the hollows and mess up the 3D rendering.
Oops. I was forgetting that gravity can be made to work for one. If you want a liquid imprinting medium to stay put on the highest relief, and indeed concentrate at the highest points, then turn the subject (or template) upside down before imprinting, and press it DOWN into linen.
There are two types of subject-to-linen presentation one can use when imprinting, what I have previously called LUWU (Linen Underneath, With Underlay) and LOTTO (Linen On Top, Then Overlay).
Use the LUWU configuration(even if easier said that done where real people are concerned). That requires painting the subject with imprinting material, then lying face DOWN into the linen to imprint the FRONTAL surface. If the medium is fairly runny and mobile, then in the brief time the subject positions himself face DOWN, the medium runs to the LOWEST points of the relief, due to gravity, which would have been the HIGHEST points when face up. It is the concentration of medium at the new lowest relief that might generate most if not all of the negative and 3D properties of the final 2D imprint.
OK, so it might be tricky to get a clean imprint via LUWU. However, the purpose in hinting at a gravity-aided model is not to suggest this was how imprinting was actually achieved, but simply to flag up the wealth of options on offer. Yes, one risks attracting unflattering references to Occam’s Razor. But having a range of options for modelling is not the same as needing to attach a host of qualifying assumptions to a model through having a limited range of options.

Further update Saturday May 9

Have just this minute taken a picture of the latest experiment in progress (imprinting off a plastic 'Galaxy Warrior" from Poundland), and inserted it as opening graphic (with a cut-and-paste to shroudstory which has just done an agreeable and benign cover on this posting).

Here's the same image after drying and pressing briefly with an electric iron:

Yes, as I said in the caption, the two heads - frontal v dorsal - should have been separated (a little) and the two images, frontal and dorsal, should have been perfectly aligned on the long axis.  As the sign used to say above the maintenance workshop at a student hall of residence I once stayed at: "The impossible we do immediately. Miracles take a little longer."

Update: 12May 2015

Here's a new result, hot from the press, correction, garage.

It's posted here first as a 'linkable' graphic. It will then be posted to Dan Porter's shroudstory site, so as to keep folk there in the picture. Where next? Maybe write a post on my  specialist shroud site that's been dormant since December last year, saying why I think this result is important. The colour you see in that pot with the handle, bottom left, may well be the one that is on the TS, albeit faded with time.

What's in the pot to give it that red-brown colour? It's the isolated gluten (the viscoelastic protein that is responsible for breadmaking dough) from wheat flour, washed free of its starch granules, then treated with nitric acid.  It's maybe a bit soon to be speculating on what is in wheat gluten protein to give so strong an orange colour with nitric acid (the so-called xanthoproteic test). My guess, for what it's worth, is the high tyrosine content of wheat gluten.  It readily nitrates with nitric acid to give the 'sepia' colour, as per TS.

The small glass dish on the right has the starch that was washed out of the wheat flour dough. It does NOT give the same red-brown colour, merely a faint yellow coloration, possibly, probably due to starch granule protein (friabilin etc, as discovered by my colleague Philip Greenwell at the previous FMBRA i.e. Flour Milling and Baking Research Association,   developer of the Chorleywood breadmaking process, now part of the Chipping Campden and Chorleywood Food Research Association

Posted to shroudstory:

May 12, 2015 at 12:13 pm
It says “figured out, sort of maybe” in the title. Might I humbly suggest there’s a bit less “maybe” now.

That’s isolated wheat flour gluten in the bowl at the back. That’s a portion of it treated with nitric acid to get the sepia (red-brown) TS-like colour in the dish bottom left. That’s the flushed-out, then gravity-sedimented starch fraction in the glass dish on the right, also treated with nitric acid, with faint yellow coloration only.
Why should wheat gluten (the protein fraction) of flour produce a orange colour with nitric acid? Answer: it’s almost certainly due to its high content of the phenolic amino acid tyrosine that readily nitrates with nitric acid in the so-called xanthoproteic reaction (used as a test for proteins).
In other words, the TS sepia colour is NOT due to dehydrated, oxidized carbohydrates, as suggested in the STURP summary. It’s due to nitrated protein formed by secondary chemical development with nitric acid of a contact imprint made from a human subject (dead or alive) using a slurry of white flour as imprinting medium.