The Shroud of Turin- was a lightly baked mummified skeleton and thermosensitized fabric used to produce the image by thermo-stencilling?

 Yup, I think I know how it was done - faking, that is, the crucified body of Christ as a faint sepia image on cloth in the holy-relic obsessed 14th century. The initial inspiration may have been
mummified human bodies, near skeletons in some cases, with which at least some medieval monks (say) may have been well acquainted.

Yes, mummified skeletons were probably a plentiful commodity in your medieval monastery, if one in Brno (the Czech Republic's second city) is anything to go by.  I was one of numerous tourists who visited there some three years ago to see the ghoulish spectacle of more recently mummified monks, still on display.

Capuchin Monastery, Brno

Here, very briefly, is what I think those monks did,. (I'll, er, flesh out the details later). They put one of their long deceased brothers in an oven (bread-baking?) and baked him until he was hot enough to quickly scorch cloth pressed against it. They probably did not have a thermometer, but if they did they would have opted perhaps for somewhere in the region of, say,  250 to 350 degrees Celsius, well below even the dullest red heat at approx. 500C  (the max temperature on an electric iron is said to be about 200 -220C, capable of scorching if one's not careful, needless to say).

The crucial next step, omitting details for the moment like hair, blood etc, was as follows. The hot skeleton was laid on the lower half or a 14ft x 3ft length of  impregnated linen, which was then doubled back at the head end and rolled back to the feet  so that both dorsal and ventral surface were "enshrouded".

The treated cloth would then be monitored closely. In a short while it would have begun to acquire a scorch-like image  (I hesitate to say "scorch" for reasons that will shortly become apparent). What's more the image would be comparable to a photographic negative - with a reversal of the light and dark one would see in a portrait or modern photograph. Why? Imagine a prominent (protuberating p) part of the body, say the hands folded over the groin region. They would be closest to the clothand produce a dark brown image, unlike the lighter image in a photo. But the eye sockets, furthest from the cloth, would leave little impression, which is the opposite a photo where they appear dark through being in shade, so to speak.

Starting with a skeleton and the technique described not only accounts for the negative image, and the 3D properties revealed by image analysis (inasmuch as the "subject" is 3D, absorbing radiant heat in inverse proportion to its distance from the shroud) but also explain the claimed X-ray like properties of the image:

See following link for an account of those X-ray like properties

I add a section later on the blood and hair. For the moment, let's address just two extra details. How was the cloth sensitised to scorch superficially in those parts closest to the hot skeleton? Check my 5 or 6 previous posts and you will find one possible method, using linen that had been lightly coated with charcoal slurry ( maybe starch and/or simple sugars too) and then dried. The charcoal acts as a thermosensitiser, absorbing heat rays (infrared), producing a light tanning effect on the part of the cloth in immediate contact with the charcoal. The chemistry might involve caramelisation, or a carbohydrate/protein reaction to form Maillard reaction products). The latter can be washed out later, leaving just the sepia "stencil" and  the bemused (overawed) medieval religious pilgrim with no clue as how it was produced. It's a process that I have dubbed thermo-stencilling.

 A thermo-stencilled image (see earlier post)

Alternatively, the cloth may simply have been impregnated with lemon juice or similar, relying on the old "invisible writing" trick we used to so as children with paper, lemon juice, a pen nib and a hot clothes iron.

What about the blood on the wrist instead of palms, which some see as lending authenticity to the Shroud (on the grounds that medieval fakers would have assumed like most that it was the palms that had been pierced by nails, rather than the wrists that would seem better able to support weight)?

Well, here's an argument that kills two birds with one stone. Firstly, the metacarpal bones of the hand are highly prominent in the Shroud image, despite being flesh-covered in life, which reinforces my skeleton theory.

But the medieval monks, looking at those metacarpals may have made an all to common mistake in assuming them to be finger bones, so placed their blood below the metacarpals, imagining they were centre- palm, when in fact they were nearer the wrist.

This explanation can account for the image being located on both sides of the cloth, as an exceedingly thin layer, with no intermediate layer. It depends on the cloth having been coated with carbohydrates that are more susceptible to scorching than cellulose, especially reducing free reducing sugars like glucose. Indeed, fruit juice (white grape juice?) may have been used. Again, that "invisible ink" effect.

Yup, this has been hastily written, I freely admit. This retired scientist knows that a new idea should be published quickly, before it becomes someone else's idea...  ;-) That's enough for now. More tomorrow.

Weblog: further experiments to reproduce, albeit approximately, the Turin Shroud by non-supernatural means, e.g. by thermo-stencilling

I ended the previous blog, posted earlier this morning, with the following words:

"Experiments are underway, which I shall report in real time, i.e. as a (web)log, which was the original meaning and intention of the “blog”, with new items being added to the top, rather bottom.  It’s a little self-indulgent, I grant you, since it supposes that visitors come back for a second or third look. Neither is the end product terribly user-friendly to someone reading a reverse chronology, so to speak. But it’s a suitable format for a reporting a lot of bitty experiments in real time – as evidence that one is still busy and interested – and more user-friendly summaries of chief findings and conclusions can come later. I’ll call it : Weblog: further experiments to reproduce, albeit approximately,  the Turin Shroud by non-supernatural means, e.g. by thermo-stencilling."

So here we go with the weblog, posted in reverse chronological order:



Experiment 2: Given that starch (from white flour") did not increase the charring of cotton by charcoal-mediated thermo-stencilling in Experiment 1, does further addition of glucose have an effect?

Here you see a 4g tablet of glucose (Boots, 92% glucose plus additives) ready to be added to the white flour suspension.

Here's the result, hoping that my make-shift labelling is legible (click picture to enlarge). Note the brown fringe on the glucose+starch area, irradiated with charcoal in columns 1 and 3, but not in the centre column 2. The enhancing effect of glucose was much clearer when viewed from the oppposite side of the cloth, without being obscured by charcoal:

Glucose/starch had a major effect, allowing an intense char patch to form after just 1 minute under the ceiling spot, not seen with starch alone How will the cloth look after washing out the charcoal?

Here's one of the strips after rinsing in cold tap water and drying. One is looking at the top surface, i.e. the one to which the charcoal was applied, the one that was irradiated. With just 1 minute irradiation, with scarcely any charring in the starch/no glucose control (upper half) there is heavy charring in the starch/glucose impregnated area.

Conclusions (and discussion) so far: 

There is a rapid browning reaction dependent on free glucose (as distinct from  starch or cellulose) that requires both the charcoal and the source of radiant heat. It may or may not require oxygen. The brown product seems to adhere firmly to the fabric, i.e. does not strip off with adhesive tape, so one still does not have a match with the reported properties of the Shroud image, but never mind, these are early days. It may well be that the product is simply caramelised sugar, comparable to what is obtained by holding a spoonful of sugar (sucrose) over a flame.

But simulating all the characteristics of the Shroud image is not the sole objective. I used an analogy on another site involving cheese, addressed to an individual who called himself “MouseinaHouse”. If one had discovered, say, Stilton cheese for the first time, and knew nothing of its origin, one might start by discovering how the pale component was formed first, from what ingredients, which starting materials, and worry about the blue veins later.

Why even bother trying to simulate anything regarding the Shroud? Why not let those who wish to regard it as the real Shroud of Christ, and formed moreover by supernatural processes (by no means axiomatic, even if it were Christ’s) ?   Three reasons. Firstly, it was the investigations by scientists back in the 80s that lent a great deal of credibility to the idea that the Shroud may be authentic – that was before the C dating. Secondly, the reasons given for rejecting the C dating that fixed it as 14^th century seems perverse to this individual – e.g. to claim that the Shroud had been repaired at the one tiny area that the Vatican had allowed to be sampled.  Thirdly, and the last straw, so to speak, was the manner in which the research by the Italian group was reported to the media, and subsequently received by the blogging community. To say that I am disheartened by the “imaginification”  (provisional term) of science is an understatement to say the least. There are times when modern so-called science, at least in the hands of certain individuals with an over-developed, some might say lurid  imagination seems determined to take us back to pre- Renaissance era.  The fact that the RC Church seems to be playing some kind of role in this, even a relatively non-aggressive one ( I hesitate to describe it as passive) comes as no surprise, given its stick-in-the-mud stance on so many other key issues, notably contraception.

The immediate aim then is to scotch the idea that because “science has not explained the Shroud ” then it’s somehow defied science, and ipso facto there must be a supernatural explanation. For a start, science has much better ways of occupying its time, now that the Shroud has been dated to the 14^th century. (Those who claim the sample was contaminated with more modern carbon should realise that the ball is in their court on that one). Secondly, it is unrealistic to expect science to explain every centuries-old item, artefact or otherwise, given no clues as to the materials used, given that age and original processing can alter the characteristics of familiar materials out of all recognition (a cooked onion is an entirely different eating experience from a raw one, and stale bread, even 10 days old, entirely different from bread that is still fresh).

Experiment 1: Does cotton char more quickly under a source of radiant heat if impregnated with a medieval source of "starch"?


What to use a source of starch? Potato starch is ruled out (Sir Walter Raleigh coming along much later). There is one reference I came across suggesting that starch for "starching" clothes in medieval times, and perhaps earlier, might have come from wheat bran. That would makle sense, given that bran has adhering flakes of starchy endosperm, i.e. white flour  - which is not pure starch, needless to say, having some protein there as well. But i was not too worried about the latter, since protein would be necessary if the browning effect with impure starch depended on protein as well to generate Maillard type reaction products. So a level teaspoonful of white flour (self-raising, since no plain flour in cupboard) was added to 250 ml water, heated just to boiling with stirring, then cooled to room temperature. I then steeped half a cotton square in the cloudy suspension, allowed to drain, then dried over the radiator, and then applied my charcoal "paint" as previously described, i.e. a slurry of powdered barbecue charcoal. When the charcoal paint had dried, each black circle was held for 1 minute under a 60W ceiling spot. The charcoal was then washed out with tap water, and the strip of cloth dried and photographed.

Result after 1 minute of irradiation:  the charred area was if anything lighter in the lower flour-impregnated half than the upper control (no flour). That admittedly qualitative result was confirmed a second time.

So despite starch being chemically more reactive than cellulose, there was no enhancement of charring by impregnating with starch. Indeed, there was possibly a little less charring.  I am relieved in a way, since the fewer variables from hypothesised pre- treatments of ancient linen, e.g. during weaving, the better.

The next experiment will be to see whether a simple reducing sugar, e.g. glucose  would affect the outcome. For that I decided to add glucose to the flour suspension, rather than test glucose alone (isolating variables one at a time can come later).

Overview - attempts to reproduce the image on the Shroud of Turin with simple technology available to medieval forgers

Is it still worth attempting to reproduce a Turin Shroud-like artefact with modern materials and techniques? Could thermo-stencilling be a valid approach?

Scorching the charcoal image onto fabric using ceiling spotlight

Appearance after washing out the charcoal - drying in progress

We have been told repeatedly that the image on the Turin Shroud has features that have never been satisfactorily reproduced. Increasingly the message has become one of: “Don’t even think about it. That image could only have been made by supernatural means”

Whilst not verbatim, words to that effect have come recently  from a group of Italian scientists no less (YES SCIENTISTS would you believe it?) who are talking about  a miraculous corona discharge, producing ultraviolet or maybe some other high energy radiation. That shows the extent to which magic is now permeating into science. (We shall overlook the tiny fact that forming an image requires not just a source of light, regardless of which part of the electromagnetic spectrum – infrared, visible, uv etc. but in addition a means of focusing that light – see my previous post). 

Am I the only one to be deeply disturbed by the blurring of the boundary between science and magic? And whilst the Vatican, to its credit, has never claimed that the Shroud is the burial cloth of Christ, or indeed of anyone from that era (its first response being to dismiss it as a fraud) is it not time for the Vatican to stop treating it as if it WERE a holy relic, and allow scientists access to more of the fabric. Is it not absurd that the C dating should be rubbished on the grounds that the sample was from a corner of the cloth that had allegedly become contaminated by frequent handling or, with even more brass neck, that it was not the original fabric, but a repair job that had used “invisible re-weaving”. It is quite simply ludicrous that scientific time and resources should be wasted in this manner.

This series of posts began with a prediction – that an image could be scorched onto linen (or other cellulosic fabrics, e.g. cotton) by drawing or painting with a black pigment, exposing the image to radiant heat, and then washing out the pigment, leaving just the scorch mark, and no clue as to its origin. That prediction was quickly confirmed using lump charcoal as the pigment initially applied dry, i.e. drawing, and then more effectively by applying as a  pasty slurry in water, i.e. as charcoal paint.

So straightaway some pretty elementary science (black things absorbs heat) could be used to undermine one of the key claims made re the Shroud, namely that it was not “painted” on the cloth, that there are no brush marks, there are no residual traces of pigment.  Using the ‘thermo-stencilling’ procedure I have described, one can indeed paint with a substance that can then be removed, leaving nothing except scorched cellulose with NO CLUE AS TO ITS ORIGIN.  

That is just a beginning. There are further claims regarding the shroud (based it has to be stressed on that tiny, possibly unrepresentative sample of material). The crucial one is that the image is not a scorch mark, at least not a typical one (whatever that is – my own reading suggests that scorching of fabric has not been a major preoccupation of carbohydrate research). We are told that the coloration does not extend the entire width of the cloth, i.e. the total diameter of cellulose fibres- that it is confined to each of the external surfaces, with no coloration in between. We are told that the coloured material can be stripped off the surface with adhesive tape. We are even shown phase-contrast microscopy of a supposed coating on the surface of the fabric, with suggestions that it represents something acquired or added in weaving, possibly starch and simple sugars used as a processing aid for weaving, and that the image is confined to that layer.

Once you envisage the image being on an applied  or accidentally  acquired coating, rather than the cloth itself, then the number of formative mechanisms increases exponentially, and it becomes increasingly less worthwhile as a scientific exercise to explain images, if one does not know the starting materials. Indeed, some might say, especially in view of the C-dating, that the onus now rest entirely on the magicians to explain how the image was formed if wishing to prove a supernatural origin, as distinct from placing the onus on scientists to disprove a supernatural origin. Scientists do not like being asked to prove negatives, i.e. that there is no known non-supernatural means of reproducing the image, that exoplanets are not made of green cheese.

However, there is still some science that can be done, based on some rudimentary info we have re the nature of early linen, whether it be medieval in origin, or even 1^st century AD. It is said that it was treated with starch, accompanied perhaps by simple sugars, which are, needless to say, close chemical relatives of cellulose.

Experiments are underway, which I shall report in real time, i.e. as a (web)log, which was the original meaning and intention of the “blog”, with new items being added to the top, rather bottom.  It’s a little self-indulgent, I grant you, since it supposes that visitors come back for a second or third look. Neither is the end product terribly user-friendly to someone reading a reverse chronology, so to speak. But it’s a suitable format for a reporting a lot of bitty experiments in real time – as evidence that one is still busy and interested – and more user-friendly summaries of chief findings and conclusions can come later. I’ll call it : Weblog: further experiments to reproduce, albeit approximately,  the Turin Shroud by non-supernatural means, e.g. by thermo-stencilling.

More progress in improving my thermo-stencilling technology for simulating the Turin Shroud

Previously I used a charcoal stick to sketch pictures on cloth, prior to fixing those images with thermal radiation (charcoal absorbs heat and light rays). But the images were rather faint, and it was difficult to remove all the charcoal by washing (thus disguising the methodology) probably because of pressure needed to draw with a stick.

As suggested earlier, I figured that a better result might be obtained by painting with  aqueous charcoal suspension ("charcoal paint") , and that has indeed proved to be the case, as should be apparent from what follows.

The lump charcoal was first reduced to a powder with a hammer, and then a little water added to the powder. That did not give a satisfactory "paint", with a lot of charcoal floating on top. As soon as a few drops of detergent were added (washing-up liquid) a relatively homogenous paste was obtained that could easily be applied to fabric with a brush as if painting.

The following pictures should be self-explanatory:

 Charcoal painted onto cloth, with paint pot in background

The next step is to dry the paint over a radiator.

Each letter of the painted word was then exposed to a few minutes radiant heat from a 60W ceiling spot lamp, and here it is viewed from the rear before washing out the charcoal "stencil". Faint smoke was visible during the roasting procedure, but nothing burst into flame. The pyrolysis (charring) seems to be self-limiting, and greatest in the regions with most paint.

Here it is, back on the radiator, drying off, after washing out the charcoal with soap and water (which proved exceptionally quick and easy). So that's a scorch image that is visible now, instead of the original charcoal.

Here we are, back on the dining table. looking at the thermo-stencilled image,and  with no trace of charcoal visible that might give a clue as to how it was formed. Painting is definitely the way to go, as distinct  from drawing, allowing one to build up the  density of heat-absorbing pigment in stages until one gets the desired intensity of  scorching. And it's much easier to wash out the charcoal, due presumably  to far less pressure from painting with a brush.Could this be how the Turin Shroud was produced?

Next experiment? It is said that the image is not formed on the cellulose fibres, but on a surface coating of starch, the latter having been used as an aid to weaving:

Link

Evidence for this is that the image can apparently be stripped off physically with adhesive tape (which is certainly not the case for scorched cotton) or reduced chemically with diimide, N2H2.

So the next step is to repeat the experiments with a starch-coated fabric. It's my guess that scorching will occur more readily with starch, which is chemically more reactive alpha-linked glucan, than with cellulose (beta-linked glucan), the latter having more extensive crystallinity due to  multiple intermolecular hydrogen bonding interactions. If scorching can be achieved quickly, then it may indeed be possible to strip off a superficial scorched layer from underlying cellulose, simulating more closely the characteristics of the Shroud. I shall have to think of an authentic (historically credible) source of starch. It certainly won't be potato starch!

Tom Chivers - re that Turin Shroud: you are the first (possibly second) person to be thermo-stencilled ...

"Tom Chivers is the Telegraph's assistant comment editor. He writes on science, culture and anything that crosses his mind."

Link to his most recent DT posting  on the Turin Shroud

 
 That's what it says at the top of Tom Chivers' Telegraph blogsite - he of the commendable breadth of interest, taking in, unusually for this day and age, a range of scientific topics (and much else besides).

But he was not always called that. In fact I once pulled his leg re his previous somewhat grandiose title ("Strategic Events Editor) - how to win friends, ha ha.... ;-)

Maybe Tom ran out of strategic events to report. Well, here's a possible candidate, says I immodestly - a simple procedure that one CAN safely try at home and which might, and may, just may, have been the technology by which the Shroud of Turin was produced in the 14th century as a fake "holy relic".

Here is a series of pictures that should tell the story without needing a lot of words.

Photograph, "shroud cloth", charcoal

Place photograph under fabric, place on glass sheet, illuminate from beneath

Completed charcoal tracing

After radiating from a 60W spot light for about 5-10 mins, viewed from reverse side before washing - selective scorching apparent.

 

 After washing out the charcoal and drying.  OK, so the image is faint (but then so is the Turin Shroud's!)

Hiya Tom. You're not looking your usual self today... Feeling a bit browned off?

The next step is to improve the image intensity. I've just made some charcoal paint, using a slurry of powdered charcoal in water with a dash of wetting agent. It paints beautifully onto cloth. The next step is to grill under a source of radiant heat, and wash out the charcoal "stencil".

(Oops. I had meant to add this to the end of the next post, the one describing use of charcoal paint. Never mind.)   Next experiment? It is said that the image is not formed on the cellulose fibres, but on a surface coating of starch, the latter having been used as an aid to weaving:


Link

Evidence for this is that the image can apparently be stripped off physically with adhesive tape (which is certainly not the case for scorched cotton) or reduced chemically with diimide, N2H2.

So the next step is to repeat the experiments with a starch-coated fabric. It's my guess that scorching will occur more readily with starch, which is chemically more reactive alpha-linked glucan, than with cellulose (beta-linked glucan), the latter having more extensive crystallinity due to  multiple intermolecular hydrogen bonding interactions. If scorching can be achieved quickly, then it may indeed be possible to strip off a superficial scorched layer from underlying cellulose, simulating more closely the characetristics of the Shroud. I shall have to think of an authentic (historically credible) source of starch. It certainly won't be potato starch!

How to make your very own Turin Shroud at home - while choosing your own image

This is a brief synopsis of the previous post. OK,  so it was a bit wordy on account of my relating the progression of an idea to a finished product, blow-by-blow so to speak.  The finished product was a recognizable image, scorched onto fabric, with no clues as to how it was created.


Well, here's my home-made "Turin shroud" with a recognizable image of a smiley.

How was it produced?  Simple. Sketch the image in charcoal on some cloth (barbecue lump charcoal will do). Then hold the cloth up close to a source of radiant heat, eg, a ceiling spot light.

Observe the rear side closely. When you see it scorch, but only in the charcoal coated areas (black pigments absorb heat, white areas reflect and stay relatively cool), remove, then wash out the charcoal with soap and water. For fuller details, see the previous post.

Here by the way is a link to an excellent site that I cannot recommend too highly, discovered purely by accident. The site's name is Silly Beliefs, and its page on the Turin Shroud is packed with telling observations.

So what next?  Posting to Tom Chivers is a complete waste of time. Not one of the 10 comments I have posted so far - describing the genesis of an idea to its practical demonstration - has earned me a single recommend, while those who snipe or nitpick are rewarded. It would be nice if Tom himself, who frequently enters the fray on his own posts, were to proffer a word or two.


So what next on the experimental front?  There's a detail that needs attending to - minor perhaps, but irritating. It is difficult to wash out all traces of the orginal charcoal - not surprising perhaps, given that it is microcrystalline graphite. That faint but residual sketch detracts somewhat from the "Turin Shroud- like" simulation.

Today I might try grinding up some charcoal, and making it into a water or oil-based paint that can then be lightly brushed on the fabric. The trouble with yesterday's procedure, using lump charcoal, unlike the artists' charcoal stick intended originally, is that one has to press quite hard to draw the image, thus grinding carbon particles into the body of the fabric.

Update October 14, 2018

First, ignore the comment below about using a desiccated 'mummy' as template. That was (over)influenced by a visit to Brno,  Czech Republic, where my wife and I saw those mummified monks in the flesh, so to speak.

No, after a further 7 or so years  of  hands-on reseacrh,  progressing from thermostencilling (Model 1) to current Model 10 (arrived at 3 or more  years ago), I'm now firmly of the belief that the TS body image is a SIMULATED ('faked') sweat imprint of the newly crucified Jesus onto Joseph of Arimatheas's 'fine linen') . It was created in the 14th century, probably by the clerics and their helpers at Geoffroy de Charny's generously-staffed private chapel in Lirey, France, and made to look as if the sweat imprint had been yellowed with 13 centuries of age. How made? Probably as a flour imprint from two recumbent adult male volunteers, aligned head to head, one face up, the other face down, smeared with oil, sprinkled with white flour, draped with wet linen, the latter then pressed down manually to access and imprint as much of the body relief as possible. Blood (correction, 'blood' ) was then added and the the linen with flour imprint was then roasted gently over red hot embers to produce the straw image colour (via Maillard reactions and final melanoidin formation comparable to bread baking) and then given a final wash with soap and water to dislodge loose surface encrustation, leaving just the faint negative (light/dark reversed) image.  (I have deliberately omitted details re the "blood" for now. Suffice it to say that a thermostable blood substitutre. eg. red clay slurry, was perhaps used in place of real blood initially,and later touched up with real blood later, after the roasting step).

Takeaway message: the TS is an ingenious SIMULATED SWEAT/BLOOD IMPRINT of medieval (14th century) fabrication. It may have been inspired by the then-celebrated 'Veil of Veronica' - alleged to be an analogous sweat/blood imprint  (face only) acquired en route to the cross. The TS trumped that, being the whole body post-crucifixion image acquired en route from cross to tomb.

The Turin Shroud - could it have been produced by thermo-stencilling?

Original (note reversed light/dark)

Photographic negative with enhancement: Image now a "positive".

See tail-end for some October 2018 updates (yes, some 7 years after this, my initial Shroud posting!)

Even now, that  faint, so-called "enigmatic" negative (tone-reversed) Shroud image is not instantly and easily explainable (especially as scientific access has been denied  by the Vatican these last 40 years since that  inconclusive STURP exploratory 5 -day visit in 1978) !

Why not?  Because one has to be willing to think 'outside the box'.  ( Seems it's no longer taught in schools and universities).

'Thinking  outside the box'  is - and always has been - this retired scientists's speciality.  So be prepared for surprises... 

Key words to look for are : SIMULATED SWEAT IMPRINT (seemingly dried and subsequently yellowed with age). You read it here first...


Start of 2011 posting: 

This is a quickie post. I'll tidy it up later. It's to show some comments I have today posted to Tom Chivers blog on the Daily Telegraph with the germ of an idea (that may or may not be original).

Tom's topic title: 

The Shroud of Turin: forgery or divine? A scientist writes


The comments set out briefly an idea that came to me suddenly this afternoon as to how that image on the Turin Shroud may/might have been produced in the 14th century by medieval "forgers", intent on producing yet another 'holy relic' to add to fragments of the 'real cross'  etc etc. Yes, holy relics were a major growth industry in the 14th century, given they could attract thousands of pilgrims to your cathedral or whatever each year - the beginnings of the travel industry...

Comment 1:


'THERMO-STENCILLING'? (don't bother googling - you read it here first ;-)

The crucial detail is that the image is a negative, i.e. parts of the original object that were well illuminated ("light") look dark and vice versa.

A negative image might at first sight suggest some kind of photography, either early primitive, or entirely accidental, or a combination of the two.

Leaving aside the nature of the photographic emulsion and photosensitive compound there is a problem with production of any image by photography. It needs either a good convex (converging) lens to bring light rays to a focus, or failing that a pinhole camera. It seems improbable(though not impossible) that either of those technologies were available even 800 years ago at a sufficient state of development, since if there had been there would surely be a host of other artefacts available from that era (e.g. grainy photographs of royalty?).

But there is another means by which an image can be produced that does not need photography, or at any rate the focusing of light from an object. One could use 'thermo-stencilling" instead. How? By taking some white fabric, and fashioning an image using black charcoal as one would a portrait, using degrees of shading rather than a line image. One would then expose the cloth to radiant heat, say from a furnace. The black areas would absorb heat and partially scorch the cloth in immediate contact with the charcoal while the white areas would reflect light and remain unscorched. The final step would then be to wash the particles of charcoal completely out of the cloth, leaving just the brown image - and  if I am not mistaken it would be a negative image, assuming the artist used the charcoal lightly for light-reflecting features of  a man's body, and more heavily for the bas-relief features that are in partial shade or reflect less light     Oops - sorry about that. Thanks Mouse (comments)  for pointing out that silly error.


By washing out the charcoal, the observer sees no evidence of the the image having been "painted" on the cloth. All that is left is a scorch mark - and being formed under a charcoal coating, it may be subtly different perhaps from one formed by direct action of hot iron or heat rays onto fabric.

Comment 2 (omitted, largely clarification in response to a query from xxxxxxx)

Comment 3 - further clarification:

Sorry, xxxxxxx  , but I don't understand your difficulty re charcoal. If you had been barbecuing, and had got charcoal dust on your shirt, would you throw your shirt away, on the assumption that it was impossible to wash out? Surely not. Even without modern detergents, charcoal, which is simply microcrystalline graphite, i.e. sheets of carbon atoms arranged as fused hexagons, giant molecules in fact, should be relatively easy to wash out.

You are not by any chance confusing charcoal with scorched or charred cloth by any chance? The procedure I propose starts by drawing on a cloth with the kind of charcoal given out in school art classes - carbonised twigs. The cloth is then "grilled", i.e. exposed to radiant heat, e.g. from red hot coals, or again, charcoal, though I hesitate to mention it, and the black, charcoal-coated areas on the cloth will heat up - and become scorched - in contrast to the white reflective areas without charcoal that will remain relatively unscorched, at least with short exposure times.

I only suggested charcoal because it is "right for the period" and probably does the job, but other black substances might serve equally well, given that black subsrtances absorb heat as well as light, provided they can be washed out after heating so as to "dispose of the evidence" so to speak as to how the negative image was produced. Please tell me if I am not making sense.

Again, I thank you for your interest, but have to say I am somewhat disappointed by the response so far. Any feasible mechanism should surely place a big question mark over the assertion of those Italian scientists that there is no known mechanism by which the image could have been produced. I maintain there is - and I have chosen to call it "thermo-stencilling".

 ......................................................................................................................................

Tomorrow I must get hold of some charcoal, and see whether or not  the idea works as predicted. I'll use a hot ring on the cooker hob as a source of radiant heat.

Update: Saturday 31 Dec 2011    I've just this minute cut up some cotton pillowcase (OK, so it's not flax/linen as per original Turin Shroud) and then cut some batten as per piccy below to create grips - left and right - that allow the cloth to be held close to a source of radiant heat without barbecuing knuckles.  Missus will add artist's charcoal to her shopping list when she goes into town this afternoon.

While waiting for the charcoal. I have been giving thought to what to use as a source of radiant heat.  The initial idea was to use the cooker hob:

But there's a potential complication there - it's not just radiant heat, but hot rising convection currents as well. It's better to isolate and study one variable at a time.

The new ceiling spots in my bathroom throw off a lot of radiant heat - downwards - in the opposite direction from rising convection currents, so I will try holding my "miniature shroud" up close to a spot.

Update  Sunday 1st Jan 2012

Well, missus was unable to get hold of artists' charcoal stick, but never mind, we'll try barbecue lump charcoal:

Watch this space folks (will try "grilling" under a spotlight as soon as missus has vacated the bathroom).

OK, so here's the charcoal outline being exposed to radiant heat from a ceiling spot, with the charcoal-side facing the lamp. Within a few minutes I began to see a sepia smile appearing on my side.

And here is the reverse side back on the table after just a few minutes of gentle grilling.  Prediction confirmed!  'Thermo-stencilling' WORKS - and given the utter simplicity of the procedure may or might well have been the method used 800 years ago to produce the Turin Shroud.

The final step is to wash out the charcoal, leaving hopefully just the scorch mark (with no clue as to how it was formed!)

Here it is after a brief rub with soap and a rinse. Not all the charcoal is removed, but enough to see that the image is now mainly in the form of a scorch mark.

The final step is to dry over the heated towel rail:

Incidentally, if you are wondering why the whole face (and those ears) are not brown, it's because of the limited diameter of my ceiling spots. I used one (60W) in the living room - bigger than the bathroom I had originally intended to use but the diameter is still only 7cm approx.

What might have been used as a souce of heat 800 years ago? Maybe a kiln or furnace (lime? glass?) with the door open...

Have just this minute posted this to Tom Chivers blog:


"Hello again everyone (and a Happy New Year to Tom). Guess what? I have just reproduced a downmarket version of the "Turin Shroud" in miniature, using simply a cotton sheet, a lump of barbecue charcoal, a source of radiant heat and a bar of soap. It's all on my own science buzz blog:

http://colinb-sciencebuzz.blog...

newsjunkie aka sciencebod

PS: Methinks, or rather mesuspects, that none of this will come as a surprise to the canny, well-informed Vatican ...    ;-)"

Update, nay, new angle, posted October 11, 2018 (nearly 7 years after this my initial Shroud posting - some 350 or more postings later!)


I drew freehand using a stick of  artist's charcoal in the initial experiment described  - Model 1 as I now call thermostencilling.

Yesterday I discovered one can IMPRINT with solid charcoal powder. What's more the imprints (of my fingers) bear an uncanny resemblance to the real things - essentially negative photograph-like images (ring any bells)?

Left: imprinted fingers onto DRY linen with powdered charcoal. Right: same but imprinted onto WET linen, as used with white flour imprinting medium in my Model 10.

Not bad eh? In fact I'm publishing the charcoal imprints here first, being in no hurry now to release new data to sindonology (which continues to ignore or indeed suppress  my Model 10, i.e. simulated sweat imprint theory). Nuff said.

Here's a link to my current posting which explains what got me thinking about charcoal imprints (if only to better visualize what one is producing with the white flour imprints in my current Model 10, now some 3 years old and more).

https://shroudofturinwithoutallthehype.wordpress.com/2018/10/05/no-mr-barrie-m-schwortz-sturp-did-not-provide-an-example-that-future-shroud-researchers-can-use-to-carefully-plan-their-own-work-sturp-showed-how-not-to-plan-or-execute-objectiv/

Saturday October 13, 2018 

Afterthought: It's suddenly occurred to me that I now have a means of comparing two entirely different mechanisms of generating a Shroud-like body-image chromophore.  The first  involves the linen only as source of raw material, the other involves an extraneous imprinting medium.

The first is the technique reported here  on this very posting back in December 2011, i.e. "thermostencilling", which I  now refer to as Model 1', but using the modification now appended, namely to imprint with finely powdered charcoal, rather than 'draw' with a charcoal stick, or, as later,  apply as wet suspension.   A source of dry radiant heat is used to 'scorch' the linen that is in immediate contct with the radiation-absorbing  elemental carbon.

The second substitutes powdered white flour for charcoal, i.e. my Model 10, developed and reported  in 2015, but again using a source of dry radiant heat for image development.

Both are expected to give a final yellow or yellow-brown imprint (after washing to remove either charcoal or loose 'toast-like' brown encrustation  in the case of Model 10).

The key question is then how the two end-results compare chemically and spectrally. At the very least,  they can potentially serve as reference standards for any future investigation of the TS body image, i.e. STURP Mark 2, Vatican-permitting.

Which Model do I consider closer to the TS body image?  Model 10, with flour imprinting, without a doubt.  I consider imprinting with flour (or some other organic, i.e. carbon/hydroge/oxygen etc -based medium in solid, powdered form being the likely means chosen by 14th century 'fakers'  to simulate, a claimed (then) 13 centuries  whole body sweat imprint  after drying and yellowing with age. The initial near invisibpe imprint (+ more visible blood) was imagined as  having been  left by the  newly crucified Jesus on Joseph of Arimathea's 'fine linen', en route from cross to rock tomb. The tone-reversed negative image, almost certainly produced by actual 14th century imprinting (NOT free-hand painting!) added that genius touch of authenticity, with a body image that was only just visible (and even then it was necessary to stand back a couple of metres to see it against off-white background).

I reckon the problem of the TS is now solved -  just think simulated sweat imprint, seemingly yellowed with age. How much longer must one wait for authenticity-fixated sindonologists to sit up and take notice one wonders?