December 1989 Print


Science and the Shroud of Turin


Part 2:
Science

Further Investigation of the Shroud of Turin

This is the second part in a series of three articles examining the Shroud of Turin in depth. Last month we looked into its history and description; this month the author brings in science's investigations.

Part 1 Part 2 Part 3

III. THE EVIDENCE OF THE MODERN SCIENTIFIC INVESTIGATIONS

Now we can introduce the main object of our discussion, and present to the reader the facts which were discovered and confirmed during the modern scientific examinations of the Shroud of Turin, to determine whether the Shroud is genuine or a 14th century forgery, and whether Jesus Christ was the man buried in this Shroud.

A. Is the Shroud Genuine or a 14th-century forgery?

1. The Photographic Evidence

When the first picture of the Shroud was taken, and it was subsequently discovered that the Shroud was actually a negative, the very important scientific implication of this discovery came to light — if the Shroud is a forgery, how then could any artist in the 14th century ever try to paint a negative of which a true positive image could not be obtained until 500 years later? But if any artist did attempt for any conceivable reason to paint this negative image on a piece of cloth, how could he check on and physically achieve his work, considering the diffusivity of the image at a near distance and its reversibility to the real life image? Such an artist would have been like a near blind man attempting to make lines and tones that are the reverse of what he knows from nature, and this after stepping back to check his work, and continuing back and forth in this fashion to make a negative which 500 years later reveals to us on a photograpy an anatomically perfect image of a scourged and crucified man! How could this be conceivably done by any man in any century?

Two well known and professional artists, Reffo and Crissetti, tried in the 19th century to paint copies of the diffusive image of the Shroud and the results were totally unsatisfactory. In this century there were other attempts made to reproduce by various means an image on cloth comparable to the image on the Shroud, but all these efforts have proven to be a failure. Not without justification was the Mandylion called in the past, "one-not-made-by-human-hands." The impossibility of reproducing the image is further supported by the fact that even none of the Byzantine icons or other representations of Jesus' face were alike. But what they all had in common were the marks on the face of Jesus discussed earlier, because they were clear to discern and not as diffusive as the face of the man on the Shroud.

 

2. The Medical Evidence

The first medical research was undertaken by a small team of medical men in France at the turn of this century. This team, led by Paul Vignon, the professor of biology at the Institute Catholique of Paris (who studied the Shroud extensively for many of the following years), discovered a considerable amount of accurate data from the first photograph. The findings were presented in 1902 to the Paris Academy by the most distinguished member of this research team. His name was Yves Delage, the professor of comparative anatomy who was an agnostic. And yet, interestingly enough, he named his lecture, "the Image of Christ Visible on the Holy Shroud of Turin." In his lecture he explained how the wounds and other markings on the image were so anatomically perfect that it was practically impossible to be drawn by a human hand.

When new and better pictures of the Shroud were taken in the 1930's, medical research was continued by Dr. P. Barbet, who conducted experiments in Paris on cadavers, to prove that the wounds visible on the Shroud were indeed those of a crucified man. Other medical researchers followed. Professor H. Moedder developed experiments with volunteers hanging from their arms, to study the physical effects on crucifixion victims as shown on the Shroud. Doctors Judica Cordigilis and Sava studied the Shroud's bloodstains, and in the 1960's Dr. D. Willis evaluated all evidence available up to that time. And most recently, Dr. R. Bucklin also provided a valuable medical work on the Shroud. All of the doctors have been fascinated by the anatomical accuracy of the image and the lifelike character of the flow of blood coming out of the wounds. Consequently, they were all convinced by the data they collected, that a crucified man was wrapped in the Shroud, and that the Shroud was, therefore, genuine.

 

3. The Pollen Evidence

A renowned Swiss criminologist, Dr. Max Frei with a botanical background (also with an international reputation as the head of the Zurich Police Scientific Laboratory) was given permission to take some dust particles off the surface of the Shroud for analysis. Among miscellaneous particles he found a number of pollen grains which have proven to be a significant discovery in determining the whereabouts of the Shroud preceding its first exposition in the mid 14th century. During the years of 1974 and 1975, Frei examined each pollen grain and cross matched it against his files of collected varieties. His early skepticism was replaced by a belief in the authenticity of the Shroud, as he identified 49 species of plants whose location was broken down to four main groups:

a) Halophyte type desert plants of the Palestine area around the Dead Sea.
b) Stepic plants, flourishing in the area of Urfa, the present name of Edessa.
c) The group of plants characteristic of the Istanbul (formerly Constantinople) environment.
d) Northern European plants found in France and Italy. The summary of these findings can be expressed in the words of Mr. Frei himself: "These plants (Halophyte type) are of great diagnostic value for our geographic studies ... a forgery produced somewhere in France during the Middle Ages in a country lacking these typical halophytes could not contain such characteristic pollen grains from the desert of Palestine." Consequently, his final report "permits the definite conclusion that the Holy Shroud is not an adulteration."

 

4. The Evidence of Scientific Investigation Between 1973-78

a. 1973 Italian Team

In 1973 a scientific team, comprised mostly of Italian scientists, investigated the Shroud. Their work was incomplete, but they found no pigment or dye in the image area. It was also revealed under the microscope that the image laid on the very top fibers of the Shroud's threads. If dye or pigment were applied by an artist, the fibers would have been penetrated below the top fibers. This confirmed earlier studies, discussed above, which concluded that the Shroud was not a painting. However, other tests, such as blood tests, proved inconclusive when standard hemoglobin tests failed to confirm blood in the bloodstained areas. Nevertheless, the scientists did acknowledge at that time that no conclusive evidence was found yet to exclude blood from the image area.


b. The Shroud of Turin Research Project

In 1977 a group of scientists formed "The Shroud of Turin Research Project" (STURP), which made additional discoveries and prepared the groundwork for the extensive and complete tests performed during their subsequent 1978 investigation. One of their most baffling discoveries was the three dimensional property of the Shroud image. Two physicists, Dr. John Jackson and Dr. Eric Juniper, found out in the U.S. Air Force Weapons Lab in New Mexico that the brightness of the image was proportionately related to the distance of the body from the cloth. This discovery, therefore, indicated that the image was formed by a three dimensional object, such as the body of a man. Furthermore, because this ratio of brightness to the body distance from the cloth was mathematically so accurate, these two scientists were able to produce a three dimensional replica of the man in the Shroud by using a VP8 Image Analyzer, which was developed for analyzing planetary and stellar photographs. Such a replica can be made from space photographs, but it is impossible to make it from normal photographs because the photographic material and lenses are not sensitive enough to reproduce, over a short distance, a minute light intensity variation on a two dimensional image.

The discovery of the three dimensional image brought to light further intriguing pieces of information. It was discovered that small round objects were placed over the eyes. After detailed study, Fr. Francis Filas, professor at Loyola University of Chicago, confirmed Jackson and Juniper's suggestion that they may be coins. He identified the one on the right side as a Lepton which was coined at the time of Pontius Pilate's governorship in Jerusalem, but only for the years of 29, 30 and 31 A.D. This discovery gives further credence to the belief that the cloth originated at the time of Jesus, because it was a Jewish custom in those days to put coins on the eyes of dead people to keep them closed. And it further explains why all the images of Jesus copied from the Shroud faithfully reproduced "heavily accentuated" owlish eyes.


c. Other Investigations

Other investigations done by the technicians J. Lorre and D. Lynn at the Jet Propulsion Lab in Pasadena clearly showed that by using the same computer assisted techniques used to study images transmitted to earth from the surface to Mars by the Viking spaceship in 1976, that there was no directionality in the image. That is, the image had no discernable brush pattern which would be visible if the painting of the image was done by the hand of an artist.

 

5. The Evidence of the 1978 Scientific Investigation

In 1977 eight members of STURP went to Turin to discuss the Shroud and obtain permission to perform a detailed analysis of it, with the main objective of answering three questions: a. What is the image composed of, b. How was the image formed, and c. Is there blood on the Shroud? After showing the replica, the extent of the preparatory work which had been done, and the detailed testing plan to the Church authorities, the permission was granted. All their preliminary work, done on the basis of the information obtained from the photographs and the recorded observations and research of other scientists, would be either confirmed or rejected during the actual tests on the Shroud.


a. The Composition of the Image

The Shroud was microscopically examined and new color pictures were taken and examined under the VP & S Image Analyzer. All previous findings were confirmed while some additional details were revealed:

1) The image is indeed superficial; that is, only the very topmost fibers of each thread are discolored. The image does not even penetrate through thread which is only .059 inch (.15 mm) thick. Further, the yellow discoloration consists of the same color throughout the whole image. That means that the color differences between the lighter and darker areas are not formed by the varying intensity of the yellow color — as is expected in a painting — but by the greater intensity of discolored fibers (more discolored fibers per given area) in the darker areas than in the lighter areas. These density differences are also related to the distance between the cloth and the body the cloth covered, thus accounting for the three dimensional quality of the image.

2) Furthermore, the discovery of the image also helped to explain the diffusivity of the image (or apparent lessening of focus as one approaches). This faintness is due to the lack of sharp boundaries between the image and nonimage areas brought about by the varying density of the discolored fibers in image areas (this peculiar characteristic is absent in paintings, being unique to the Shroud). The eye can see the boundaries of the diffusive image only when the image is compressed into a smaller portion of the total field of vision, as when viewed from a distance, or when photographed. 


b. The Image Formation

The second question of how the image was formed has been the most complex and baffling mystery, and has not yet been satisfactorily explained. However, it does not hamper our efforts to determine whether the Shroud is Jesus Christ's burial cloth or not. On the contrary, this inability of the modern scientists to explain the process of image formation gives further credence to its supernatural origin.

To facilitate the study of image formation the examination was divided into two groups: the artificial, and the natural processes. The supernatural origin was not even considered, thus eliminating the possibility of a bias towards the religious aspects of the Shroud, and concentrating instead on explaining the phenomena from the natural point of view. There were four general theories of image formation to be examined: 1) the painted image, 2) the chemical agent, 3) the Vapograph Theory, and 4) the scorch effect.

1) Tile Painted Image

A number of tests were employed to determine any amounts of pigment, dyes, ink or any other chemical, which might have been used to paint the image. The microscopic observation confirmed again the previous conclusions. No pigment particles were found even under SOX magnification. The yellow color of the image did not penetrate below the very topmost fibers. Also, there was no evidence for the flow of liquids throughout the cloth on a microscopic level, as would be the case if any inorganic agent such as ink was used. Further, X-ray fluorescence tests measured the composition of the elements, and radiography recorded changes in the density of the shroud. None of them detected any particles which would support the painting theory. Other tests, which also could not find foreign substances on the Shroud, were photoelectric spectrophotometry, photoelectric and photographic fluorescence, and direct observation in visible light. "Sticky tape" samples were taken from all over the Shroud. The miscellaneous particles which adhered to the removed tapes consisted of insect parts, pollen, wax, wool, etc., but none of them could account for the yellow discoloration of the fibers. Some fragments of the yellowed and nonyellowed fibers were found on the tapes. These fragments were subjected to an intense testing which included treatment with acids, bases, organic solvents, and strong oxidants. Again it was confirmed that the Shroud contained no pigments, dyes, etc., which could be used to paint or cause the image on the Shroud, and that the yellowed fibers were resistant to any effects of chemical testing.

It was concluded that the image was not caused by any pigment or any other foreign agent, but was the result of the degradation of cellulose, the plant material in linen fibers. The cellulose fibers in the image areas had been dehydrated, as opposed to the hydrated fibers in the nonimage areas. The dehydrated fibers reflected the light to a degree proportional to its density, and caused the visible image. The scientists also confirmed that there were no variations in density in the areas burned in the fire of 1532 compared to areas located farther from the burned parts. There also were no brush marks or directionality detectable on the image area. Therefore, the STURP scientists categorically rejected the past belief that the Shroud was a painting, stating in their summary, "we have found no evidence to suggest that the visible image results from a pigment on the cloth."

2) The Chemical Agents

The second theory included all theories which held that the chemical composition of the cellulose in the fibers had been changed by a chemical agent. The most important of these theories was the one which postulated a latent image idea. That is to say, by application of sensitizing agents such as skin secretion, myrrh, and body oil, the image would gradually be formed by the combination of heat (or by aging of the linen) and body pressure during the direct contact of the body with the cloth. However, during the investigation serious shortcomings were exposed which led to the rejection of this theory.

First of all, no sensitizing agents were found on the Shroud. Another problem was how to apply the agents thinly enough to sensitize only the topmost fibers. The third objection was made in regard to forming the image by body pressure. The tests showed that even though the back image is slightly more distinct than the front image, the small difference between these images is greatly out of proportion to the pressure differences between the part of the cloth that the body laid on and the top part, which pressed against the body only by its own weight. But the most important obstacle to accepting this theory is the three dimensionality of the image. These sensitizing objects had to form the image by direct contact. How could this theory then account for the three dimensionality of the image in the areas where the cloth did not touch the body, if this worked on the principle of varying cloth body distance relationship?

3) The Vapograph Theory

This theory really belongs with those grouped in the preceding theory, but because it is the oldest theory, it was treated separately. Paul Vignon, who led the first medical research group in 1900, suggested that the crucified man buried in the cloth would have perspired a morbid sweat containing urea, and as the urea would have fermented into carbon dioxide and ammonia, ammonia would have diffused from the body to the cloth, reacting with aloes and olive oil to produce an image. This theory was also rejected on several counts. First, it was not possible for gas diffusion, which is very random, to form a highly detailed image. Chemists of the STURP also concluded that not enough ammonia would be produced from the morbid sweat to effect the image formation. Furthermore, such a reaction would be absorbed beyond the topmost fibers of the linen and thus could not explain the superficiality of the image. Lastly, this theory could not account for the three dimensionality of the image, the stability to both heat and water (the image formed by this process would be affected by heat and water—the 1532 fire accident which damaged the Shroud showed no such effects), and for the fact that no above described image forming agents were found on the Shroud.

4) The Scorch Effect

That the image was made by a scorch is the most plausible theory because it does explain some of the characteristics of the Shroud. Nevertheless, several questions regarding the validity of the scorch theory remain to be solved, and for that matter they may never be solved by purely scientific research because of the closeness of the Shroud's qualities to the supernatural.

Prior to the 1978 investigation, it was believed that the image could have been produced by some kind of scorch. Experimentally, it was found that cellulose fibers can be yellowed by a scorch the same way as those on the Shroud are yellowed. Also, the scorch on the Shroud caused by the 1532 fire has similar optical properties as the image on the Shroud, but not identical ones. The fire scorches are visibly redder than the body image and also fluoresce differently under ultraviolet light. Nevertheless, the slight differences can be explained by the different conditions under which they were formed. The fire of 1532 occurred in a sealed box, in a substantially oxygen free environment. This was proven experimentally, and the scorch this experiment produced had similar properties to the fire scorch on the Shroud.(19) However, the most difficult problem the scientists faced was the question of how the image was transferred to the cloth.

It was the major objection to the acceptance of the scorch hypothesis before the 1978 examination as well as after, since this transfer mechanism could not be explained by any scientist. Before 1978, J. Jackson showed mathematically that simple radiation emitted by a three dimensional body could not have produced the density shading and resolution so prominent in the Shroud image. He believed that this problem could be circumvented if the radiation source or something between the cloth and the body could vary the intensity of the heat or light. But then this variation would distort the image. By solving one problem, his suggestion would create another. Therefore, not all the scientists agreed with the scorch hypothesis, and even though it could not be explained from the purely scientific point of view, many members of the team stopped well short of considering that a dead man could or would radiate sufficient light and heat to scorch his burial cloth. So in the words of the STURP scientists, it is "an ongoing mystery."


c. The Blood on the Shroud

The third question involved a separate yet very important problem; namely, that the 1973 investigation failed to provide conclusive evidence that the bloodstained areas on the Shroud were indeed blood. To settle this question, the team members examined the bloodstained areas with a complete set of optical tests throughout the electromagnetic spectrum. Sticky tape samples, which contained parts of blood stained fabrics, were examined under a microscope to observe the spectrum of the visible light transmitted from them. The results of the tests suggested that hemoglobin was a component of the color. To confirm this possibility, the iron was removed from the samples and tested to determine the presence of porphyrin, a component of blood. This substance was found to be present. Thus it was strongly indicated that the bloodstained areas indeed contained blood. Several other tests confirmed the presence of blood. Both protein and iron were detected in the bloodstained areas. The conclusion of the team was that the bloodstained areas were very probably stained by real blood.

 

6) Conclusion

The 1978 scientific investigation represented the most extensive and detailed study of any known relic, since it was performed by very expensive, ultra sophisticated, and accurate equipment used in the space program, and was handled by experienced scientists, who performed an impartial and truly scientific investigation. With the exception of image formation, this investigation positively established that the image is superficial, and thus not made by human hands, and that there is real blood on the Shroud. It further confirmed the results of STURP preliminary work regarding the extraordinary characteristics; the "secrets," of the Shroud of Turin. They are summarized below:

  1. Negative: The image on the Shroud is a negative.
  2. No Pigment, Dye or Ink: None of these agents, necessary for painting, were found.
  3. Three Dimensional: A three dimensional image was produced from a two dimensional photograph.
  4. Directionless: The image was formed by a nondirectional process.
  5. Superficiality: The image's discoloration reaches only the very topmost fibers.
  6. Chemically and Water Stable: The coloration was not affected by any standard chemical agents or by water.
  7. Thermally Stable: Even the parts of the image closest to the burns of the 1532 fire have the same color as the most remote parts.

 

Even though a completely natural explanation of the image formation on the Shroud has eluded the scientists, which only strengthens our conviction of the miraculous nature of the Shroud, the 1973 and 1978 scientific investigations, plus the photographic, medical, and pollen evidence, have provided significant and ample evidence, which cannot be discarded or ignored. The image on the Shroud was made by the body of a real man buried in a real tomb and, consequently, the Shroud is a real artifact, and not a forgery of the 14th century.