242 



NA TURE 



[January 15, 1903 



•new " evidences," but who is simply anxious to know the 

 actual facts of the case, will probably come to the con- 

 clusion that Dr. Yignon is either the victim of credulity 

 or that he has overdone his evidence to such an extent 

 as to have damaged his own reputation as an expert 

 scientific witness. The plates certainly do not tally with 

 the details of the markings as described in the text ; but 

 here again it may be that there is much lost by the 

 heliographic reproduction and that the author is 

 describing the original photographic plate, which he is 

 careful to inform, us was taken by M. Pia on an Edward 

 50 x 60 isbchromatic film sensitive to yellow, with a 

 yellow screen, a Voigtlander lens, a diaphragm of 7 mm. 

 diameter and an exposure of 18 minutes, the shroud 

 being illuminated from the front by two powerful arc 

 lights at 10 yards' distance from the surface. We will 

 therefore again waive an objection which might be raised 

 against the author's special pleading on behalf of the 

 shroud, and we will admit that there are marks on the 

 face, body and limbs in the original plate which we 

 cannot see in the heliogravures reproduced from it — 

 certainly no such marks are distinctly recognisable in 

 the front view, whatever interpretation may be put on 

 the blotched appearance on the body in the back view. 



The simplest, the most obvious and the only straight- 

 forward answer to the question how the image was 

 produced is that it is a time-worn painting — how, when or 

 why executed being beyond our province of inquiry in 

 these columns. Dr. Vignon, however, is so emphatic in 

 his repudiation of this idea that he fires off a whole 

 battery of arguments in the sixth chapter in order to 

 demolish the sceptics who from the fourteenth century 

 downwards have taken this not altogether unreasonable 

 view of the relic. One or two of these arguments may be 

 dealt with on their own merits as appealing to scientific 

 principles. He lays very much stress, for example, upon 

 the circumstance that the impression is a negative one, 

 arguing therefrom that no forger could possibly have 

 painted a figure intentionally with lights and shades 

 reversed. May we ask why not ? As an artistic feat it 

 does not seem altogether impossible, and distinguished 

 artists whom the reviewer has consulted inform him that, 

 not only is such a style easy of execution, but that a 

 forger who wished deliberately to convey the impression 

 that the image was produced by contact of the body with 

 * the shroud would, if skilful, intentionally adopt such an 

 artifice. Then again, it is stated (p. 123, English ed.) 

 that the image cannot be a painting (i.e. in pigment) 

 because it would have faded with the lapse of time 

 instead of becoming darker. Again we ask why ? In 

 the first place, where is the evidence that the image has 

 become darker? In the next place, accepting Dr. 

 Vignon's own explanation, which shall be considered 

 subsequently, why should a " vaporographic print " (to use 

 the author's term) be more permanent than a painting ? 

 An organic colouring-matter developed on the linen by 

 the hypothetical process advocated in this work is not 

 more likely to withstand the influence of time than a 

 painting. The argument appears to be : — It has not 

 faded, therefore it is not a painting. It is not a painting, 

 therefore it is a chemical (vaporographic) impression. 

 Readers of this review will see that little value can be 

 attached to such inferences. 



NO. 1733, VOL. 67] 



Having dismissed the theory of artistic forgery — at 

 any rate to his own satisfaction — the author proceeds 

 to demolish the view that the image is a contact im- 

 pression. With this conclusion we quite agree. The 

 only way that such an image could be produced by 

 contact would be for the body to be uniformly coated 

 with pigment and then for the supple shroud to have 

 been pressed over and into every elevation and de- 

 pression in the body. We are all familiar with the 

 appearance of images produced by such means, and a 

 glance at the figure on the shroud with all the details of 

 the features and the hair will suffice to show that such an 

 impression on linen, however supple, could never have 

 been obtained by mechanical contact — even supposing 

 the preliminary preparation of the body with pigment 

 were conceded. Nothing short of a plaster cast could 

 reproduce features such as appear in the plates. The 

 martyrdom which Dr. Yignon must have suffered in 

 allowing his face (with a false beard) to be smeared with 

 red chalk in order to see what kind of impression could 

 be obtained from it by such means will be credited to 

 his zeal, although the publication of the blurred results in 

 the form of a heliogravure plate seems quite superfluous. 



Having thus shown how the image could not have 

 been produced, the author proceeds to the development 

 of his own hypothesis. The impression is not a photo- 

 graphic negative in the ordinary sense, but it is a genuine 

 chemical impression produced by emanations from the 

 body acting on the shroud, " sensitised " by the materials 

 used for its impregnation. The emanations were not of 

 the same kind as those proceeding from radio-active sub- 

 stances, but were more of the nature of vapours. Appeal 

 is made to Dr. W. J. Russell's experiments in order to 

 show the analogy between the images produced by the 

 emanations from zinc, resinous substances, &c, and that 

 on the shroud. Prof. Colson has cooperated with the 

 author, and between them they have produced what by 

 courtesy the writer of this notice proposes to call Russell- 

 types of coins and busts (prepared by coating with zinc 

 powder) on photographic plates. 1 Photographic repro- 

 ductions of these are given in the volume under notice. 

 Krom these figures, it will be seen that the impressions 

 produced are really very poor as compared with the 

 originals. The head on the coin, for example, is full of 

 detail ; its Russelltype, after photographic reversal, shows 

 but a blurred and hazy image Of course, the emanations 

 from the body did not consist of zinc vapour, nor was the 

 shroud coated with gelatino-bromide emulsion, so there 

 maybe no real analogy between the images — even on the 

 " vaporographic " theory of Dr. Vignon. The emanations 

 of the body, according to the author, proceeded from 

 " febrile sweat" which bathed every portion of the body, 

 hair included, and the sensitive material which enabled 

 the shroud to receive the impression was, or may have 

 been, a mixture of oil and aloes. There is nothing 

 antecedently improbable in the supposition that emana- 

 tions from a dead body, especially if ammoniacal as sup- 

 posed by the author, may produce a coloured impression 

 on a sensitive vegetable colouring-matter. So far there 

 is just enough vraisemblance in the hypothesis to lead the 



1 Prof. Colson, by the way, has come to the conclusion that the emanations 

 from zinc really consist of zinc particles, and it is these which penerate the 

 sensitive surface and produce the photographic effect. This explanatw n i, 

 at variance with the hydrogen peroxide theoiy of Russell. 



