The Red Thumb Mark

by R. Austin Freeman

  CHAPTER XVI

  THORNDYKE PLAYS HIS CARD

  As Thorndyke took his place in the box I looked at him with a sense ofunreasonable surprise, feeling that I had never before fully realisedwhat manner of man my friend was as to his externals. I had often notedthe quiet strength of his face, its infinite intelligence, itsattractiveness and magnetism; but I had never before appreciated whatnow impressed me most: that Thorndyke was actually the handsomest man Ihad ever seen. He was dressed simply, his appearance unaided by theflowing gown or awe-inspiring wig, and yet his presence dominated thecourt. Even the judge, despite his scarlet robe and trappings of office,looked commonplace by comparison, while the jurymen, who turned to lookat him, seemed like beings of an inferior order. It was not alone thedistinction of the tall figure, erect and dignified, nor the power andmassive composure of his face, but the actual symmetry and comeliness ofthe face itself that now arrested my attention; a comeliness that madeit akin rather to some classic mask, wrought in the ivory-toned marbleof Pentelicus, than to the eager faces that move around us in the hurryand bustle of a life at once strenuous and trivial.

  "You are attached to the medical school at St. Margaret's Hospital, Ibelieve, Dr. Thorndyke?" said Anstey.

  "Yes. I am the lecturer on Medical Jurisprudence and Toxicology."

  "Have you had much experience of medico-legal inquiries?"

  "A great deal. I am engaged exclusively in medico-legal work."

  "You heard the evidence relating to the two drops of blood found in thesafe?"

  "I did."

  "What is your opinion as to the condition of that blood?"

  "I should say there is no doubt that it had been artificiallytreated--probably by defibrination."

  "Can you suggest any explanation of the condition of that blood?"

  "I can."

  "Is your explanation connected with any peculiarities in the thumb-printon the paper that was found in the safe?"

  "It is."

  "Have you given any attention to the subject of finger-prints?"

  "Yes. A great deal of attention."

  "Be good enough to examine that paper" (here the usher handed toThorndyke the memorandum slip). "Have you seen it before?"

  "Yes. I saw it at Scotland Yard."

  "Did you examine it thoroughly?"

  "Very thoroughly. The police officials gave me every facility and, withtheir permission, I took several photographs of it."

  "There is a mark on that paper resembling the print of a human thumb?"

  "There is."

  "You have heard two expert witnesses swear that that mark was made bythe left thumb of the prisoner, Reuben Hornby?"

  "I have."

  "Do you agree to that statement?"

  "I do not."

  "In your opinion, was the mark upon that paper made by the thumb of theprisoner?"

  "No. I am convinced that it was not made by the thumb of Reuben Hornby."

  "Do you think that it was made by the thumb of some other person?"

  "No. I am of opinion that it was not made by a human thumb at all."

  At this statement the judge paused for a moment, pen in hand, and staredat Thorndyke with his mouth slightly open, while the two experts lookedat one another with raised eyebrows.

  "By what means do you consider that the mark was produced?"

  "By means of a stamp, either of indiarubber or, more probably, ofchromicized gelatine."

  Here Polton, who had been, by degrees, rising to an erect posture, smotehis thigh a resounding thwack and chuckled aloud, a proceeding thatcaused all eyes, including those of the judge, to be turned on him.

  "If that noise is repeated," said the judge, with a stony stare at thehorrified offender--who had shrunk into the very smallest space that Ihave ever seen a human being occupy--"I shall cause the person who madeit to be removed from the court."

  "I understand, then," pursued Anstey, "that you consider thethumb-print, which has been sworn to as the prisoner's, to be aforgery?"

  "Yes. It is a forgery."

  "But is it possible to forge a thumb-print or a finger-print?"

  "It is not only possible, but quite easy to do."

  "As easy as to forge a signature, for instance?" "Much more so, andinfinitely more secure. A signature, being written with a pen, requiresthat the forgery should also be written with a pen, a process demandingvery special skill and, after all, never resulting in an absolute_facsimile_. But a finger-print is a stamped impression--the finger-tipbeing the stamp; and it is only necessary to obtain a stamp identical incharacter with the finger-tip, in order to produce an impression whichis an absolute _facsimile_, in every respect, of the original, andtotally indistinguishable from it."

  "Would there be no means at all of detecting the difference between aforged finger-print and the genuine original?"

  "None whatever; for the reason that there would be no difference todetect."

  "But you have stated, quite positively, that the thumb-print on thispaper is a forgery. Now, if the forged print is indistinguishable fromthe original, how are you able to be certain that this particular printis a forgery?"

  "I was speaking of what is possible with due care, but, obviously, aforger might, through inadvertence, fail to produce an absolute_facsimile_ and then detection would be possible. That is what hashappened in the present case. The forged print is not an absolute_facsimile_ of the true print. There is a slight discrepancy. But, inaddition to this, the paper bears intrinsic evidence that thethumb-print on it is a forgery." "We will consider that evidencepresently, Dr. Thorndyke. To return to the possibility of forging afinger-print, can you explain to us, without being too technical, bywhat methods it would be possible to produce such a stamp as you havereferred to?"

  "There are two principal methods that suggest themselves to me. Thefirst, which is rather crude though easy to carry out, consists intaking an actual cast of the end of the finger. A mould would be made bypressing the finger into some plastic material, such as fine modellingclay or hot sealing wax, and then, by pouring a warm solution ofgelatine into the mould, and allowing it to cool and solidify, a castwould be produced which would yield very perfect finger-prints. But thismethod would, as a rule, be useless for the purpose of the forger, as itcould not, ordinarily, be carried out without the knowledge of thevictim; though in the case of dead bodies and persons asleep orunconscious or under an anaesthetic, it could be practised with success,and would offer the advantage of requiring practically no technicalskill or knowledge and no special appliances. The second method, whichis much more efficient, and is the one, I have no doubt, that has beenused in the present instance, requires more knowledge and skill.

  "In the first place it is necessary to obtain possession of, or accessto, a genuine finger-print. Of this finger-print a photograph is taken,or rather, a photographic negative, which for this purpose requires tobe taken on a reversed plate, and the negative is put into a specialprinting frame, with a plate of gelatine which has been treated withpotassium bichromate, and the frame is exposed to light.

  "Now gelatine treated in this way--chromicized gelatine, as it iscalled--has a very peculiar property. Ordinary gelatine, as is wellknown, is easily dissolved in hot water, and chromicized gelatine isalso soluble in hot water as long as it is not exposed to light; but onbeing exposed to light, it undergoes a change and is no longer capableof being dissolved in hot water. Now the plate of chromicized gelatineunder the negative is protected from the light by the opaque parts ofthe negative, whereas the light passes freely through the transparentparts; but the transparent parts of the negative correspond to the blackmarks on the finger-print, and these correspond to the ridges on thefinger. Hence it follows that the gelatine plate is acted upon by lightonly on the parts corresponding to the ridges; and in these parts thegelatine is rendered insoluble, while all the rest of the gelatine issoluble. The gelatine plate, which is cemented to a thin plate of metalfor support, is now carefully washed with hot water, by which th
esoluble part of the gelatine is dissolved away leaving the insolublepart (corresponding to the ridges) standing up from the surface. Thusthere is produced a _facsimile_ in relief of the finger-print havingactual ridges and furrows identical in character with the ridges andfurrows of the finger-tip. If an inked roller is passed over thisrelief, or if the relief is pressed lightly on an inked slab, and thenpressed on a sheet of paper, a finger-print will be produced which willbe absolutely identical with the original, even to the little whitespots which mark the orifices of the sweat glands. It will be impossibleto discover any difference between the real finger-print and thecounterfeit because, in fact, no difference exists."

  "But surely the process you have described is a very difficult andintricate one?"

  "Not at all; it is very little more difficult than ordinary carbonprinting, which is practised successfully by numbers of amateurs.Moreover, such a relief as I have described--which is practicallynothing more than an ordinary process block--could be produced by anyphoto-engraver. The process that I have described is, in all essentials,that which is used in the reproduction of pen-and-ink drawings, and anyof the hundreds of workmen who are employed in that industry could makea relief-block of a finger-print, with which an undetectable forgerycould be executed."

  "You have asserted that the counterfeit finger-print could not bedistinguished from the original. Are you prepared to furnish proof thatthis is the case?"

  "Yes. I am prepared to execute a counterfeit of the prisoner'sthumb-print in the presence of the Court."

  "And do you say that such a counterfeit would be indistinguishable fromthe original, even by the experts?"

  "I do."

  Anstey turned towards the judge. "Would your lordship give yourpermission for a demonstration such as the witness proposes?"

  "Certainly," replied the judge. "The evidence is highly material. How doyou propose that the comparison should be made?" he added, addressingThorndyke.

  "I have brought, for the purpose, my lord," answered Thorndyke, "somesheets of paper, each of which is ruled into twenty numbered squares. Ipropose to make on ten of the squares counterfeits of the prisoner'sthumb-mark, and to fill the remaining ten with real thumb-marks. Ipropose that the experts should then examine the paper and tell theCourt which are the real thumb-prints and which are the false."

  "That seems a fair and efficient test," said his lordship. "Have you anyobjection to offer, Sir Hector?"

  Sir Hector Trumpler hastily consulted with the two experts, who weresitting in the attorney's bench, and then replied, without muchenthusiasm--

  "We have no objection to offer, my lord."

  "Then, in that case, I shall direct the expert witnesses to withdrawfrom the court while the prints are being made."

  In obedience to the judge's order, Mr. Singleton and his colleague roseand left the court with evident reluctance, while Thorndyke took from asmall portfolio three sheets of paper which he handed up to the judge.

  "If your lordship," said he, "will make marks in ten of the squares ontwo of these sheets, one can be given to the jury and one retained byyour lordship to check the third sheet when the prints are made on it."

  "That is an excellent plan," said the judge; "and, as the information isfor myself and the jury, it would be better if you came up and performedthe actual stamping on my table in the presence of the foreman of thejury and the counsel for the prosecution and defence."

  In accordance with the judge's direction Thorndyke stepped up on thedais, and Anstey, as he rose to follow, leaned over towards me.

  "You and Polton had better go up too," said he: "Thorndyke will wantyour assistance, and you may as well see the fun. I will explain to hislordship."

  He ascended the stairs leading to the dais and addressed a few words tothe judge, who glanced in our direction and nodded, whereupon we bothgleefully followed our counsel, Polton carrying the box and beaming withdelight.

  The judge's table was provided with a shallow drawer which pulled out atthe side and which accommodated the box comfortably, leaving the smalltable-top free for the papers. When the lid of the box was raised, therewere displayed a copper inking-slab, a small roller and the twenty-four"pawns" which had so puzzled Polton, and on which he now gazed with atwinkle of amusement and triumph.

  "Are those all stamps?" inquired the judge, glancing curiously at thearray of turned-wood handles.

  "They are all stamps, my lord," replied Thorndyke, "and each is takenfrom a different impression of the prisoner's thumb."

  "But why so many?" asked the judge.

  "I have multiplied them," answered Thorndyke, as he squeezed out a dropof finger-print ink on to the slab and proceeded to roll it out into athin film, "to avoid the tell-tale uniformity of a single stamp. And Imay say," he added, "that it is highly important that the experts shouldnot be informed that more than one stamp has been used."

  "Yes, I see that," said the judge. "You understand that, Sir Hector," headded, addressing the counsel, who bowed stiffly, clearly regarding theentire proceeding with extreme disfavour.

  Thorndyke now inked one of the stamps and handed it to the judge, whoexamined it curiously and then pressed it on a piece of waste paper, onwhich there immediately appeared a very distinct impression of a humanthumb. "Marvellous!" he exclaimed. "Most ingenious! Too ingenious!" Hechuckled softly and added, as he handed the stamp and the paper to theforeman of the jury: "It is well, Dr. Thorndyke, that you are on theside of law and order, for I am afraid that, if you were on the otherside, you would be one too many for the police. Now, if you are ready,we will proceed. Will you, please, stamp an impression in square numberthree."

  Thorndyke drew a stamp from its compartment, inked it on the slab, andpressed it neatly on the square indicated, leaving there a sharp, clearthumb-print.

  The process was repeated on nine other squares, a different stamp beingused for each impression. The judge then marked the ten correspondingsquares of the other two sheets of paper, and having checked them,directed the foreman to exhibit the sheet bearing the false thumb-printsto the jury, together with the marked sheet which they were to retain,to enable them to check the statements of the expert witnesses. Whenthis was done, the prisoner was brought from the dock and stood besidethe table. The judge looked with a curious and not unkindly interest atthe handsome, manly fellow who stood charged with a crime so sordid andout of character with his appearance, and I felt, as I noted the look,that Reuben would, at least, be tried fairly on the evidence, withoutprejudice or even with some prepossession in his favour.

  With the remaining part of the operation Thorndyke proceeded carefullyand deliberately. The inking-slab was rolled afresh for each impression,and, after each, the thumb was cleansed with petrol and thoroughlydried; and when the process was completed and the prisoner led back tothe dock, the twenty squares on the paper were occupied by twentythumb-prints, which, to my eye, at any rate, were identical incharacter.

  The judge sat for near upon a minute poring over this singular documentwith an expression half-way between a frown and a smile. At length, whenwe had all returned to our places, he directed the usher to bring in thewitnesses.

  I was amused to observe the change that had come over the experts in theshort interval. The confident smile, the triumphant air of laying down atrump card, had vanished, and the expression of both was one of anxiety,not unmixed with apprehension. As Mr. Singleton advanced hesitatingly tothe table, I recalled the words that he had uttered in his room atScotland Yard; evidently his scheme of the game that was to end in aneasy checkmate, had not included the move that had just been made.

  "Mr. Singleton," said the judge, "here is a paper on which there aretwenty thumb-prints. Ten of them are genuine prints of the prisoner'sleft thumb and ten are forgeries. Please examine them and note down inwriting which are the true prints and which are the forgeries. When youhave made your notes the paper will be handed to Mr. Nash."

  "Is there any objection to my using the photograph that I have with mefo
r comparison, my lord?" asked Mr. Singleton.

  "I think not," replied the judge. "What do you say, Mr. Anstey?"

  "No objection whatever, my lord," answered Anstey.

  Mr. Singleton accordingly drew from his pocket an enlarged photograph ofthe thumb-print and a magnifying glass, with the aid of which heexplored the bewildering array of prints on the paper before him; and ashe proceeded I remarked with satisfaction that his expression becamemore and more dubious and worried. From time to time he made an entry ona memorandum slip beside him, and, as the entries accumulated, his frowngrew deeper and his aspect more puzzled and gloomy.

  At length he sat up, and taking the memorandum slip in his hand,addressed the judge.

  "I have finished my examination, my lord."

  "Very well. Mr. Nash, will you kindly examine the paper and write downthe results of your examination?"

  "Oh! I wish they would make haste," whispered Juliet. "Do you think theywill be able to tell the real from the false thumb-prints?"

  "I can't say," I replied; "but we shall soon know. They looked all aliketo me."

  Mr. Nash made his examination with exasperating deliberateness, andpreserved throughout an air of stolid attention; but at length he, too,completed his notes and handed the paper back to the usher.

  "Now, Mr. Singleton," said the judge, "let us hear your conclusions. Youhave been sworn."

  Mr. Singleton stepped into the witness-box, and, laying his notes on theledge, faced the judge.

  "Have you examined the paper that was handed to you?" asked Sir HectorTrumpler.

  "I have."

  "What did you see on the paper?"

  "I saw twenty thumb-prints, of which some were evident forgeries, somewere evidently genuine, and some were doubtful."

  "Taking the thumb-prints _seriatim_, what have you noted about them?"

  Mr. Singleton examined his notes and replied--"The thumb-print on squareone is evidently a forgery, as is also number two, though it is apassable imitation. Three and four are genuine; five is an obviousforgery. Six is a genuine thumb-print; seven is a forgery, though a goodone; eight is genuine; nine is, I think, a forgery, though it is aremarkably good imitation. Ten and eleven are genuine thumb-marks;twelve and thirteen are forgeries; but as to fourteen I am verydoubtful, though I am inclined to regard it as a forgery. Fifteen isgenuine, and I think sixteen is also; but I will not swear to it.Seventeen is certainly genuine. Eighteen and nineteen I am ratherdoubtful about, but I am disposed to consider them both forgeries.Twenty is certainly a genuine thumb-print."

  As Mr. Singleton's evidence proceeded, a look of surprise began to makeits appearance on the judge's face, while the jury glanced from thewitness to the notes before them and from their notes to one another inundisguised astonishment.

  As to Sir Hector Trumpler, that luminary of British jurisprudence wasevidently completely fogged; for, as statement followed statement, hepursed up his lips and his broad, red face became overshadowed by anexpression of utter bewilderment.

  For a few seconds he stared blankly at his witness and then dropped onto his seat with a thump that shook the court.

  "You have no doubt," said Anstey, "as to the correctness of yourconclusions? For instance, you are quite sure that the prints one andtwo are forgeries?"

  "I have no doubt."

  "You swear that those two prints are forgeries?"

  Mr. Singleton hesitated for a moment. He had been watching the judge andthe jury and had apparently misinterpreted their surprise, assuming itto be due to his own remarkable powers of discrimination; and hisconfidence had revived accordingly.

  "Yes," he answered; "I swear that they are forgeries."

  Anstey sat down, and Mr. Singleton, having passed his notes up to thejudge, retired from the box, giving place to his colleague.

  Mr. Nash, who had listened with manifest satisfaction to the evidence,stepped into the box with all his original confidence restored. Hisselection of the true and the false thumb-prints was practicallyidentical with that of Mr. Singleton, and his knowledge of this fact ledhim to state his conclusions with an air that was authoritative and evendogmatic.

  "I am quite satisfied of the correctness of my statements," he said, inreply to Anstey's question, "and I am prepared to swear, and do swear,that those thumb-prints which I have stated to be forgeries, areforgeries, and that their detection presents no difficulty to anobserver who has an expert acquaintance with finger-prints."

  "There is one question that I should like to ask," said the judge, whenthe expert had left the box and Thorndyke had re-entered it to continuehis evidence. "The conclusions of the expert witnesses--manifestly _bonafide_ conclusions, arrived at by individual judgement, without collusionor comparison of results--are practically identical. They are virtuallyin complete agreement. Now, the strange thing is this: their conclusionsare wrong in every instance" (here I nearly laughed aloud, for, as Iglanced at the two experts, the expression of smug satisfaction on theircountenances changed with lightning rapidity to a ludicrous spasm ofconsternation); "not sometimes wrong and sometimes right, as would havebeen the case if they had made mere guesses, but wrong every time. Whenthey are quite certain, they are quite wrong; and when they aredoubtful, they incline to the wrong conclusion. This is a very strangecoincidence, Dr. Thorndyke. Can you explain it?"

  Thorndyke's face, which throughout the proceedings had been asexpressionless as that of a wooden figurehead, now relaxed into a drysmile.

  "I think I can, my lord," he replied. "The object of a forger inexecuting a forgery is to produce deception on those who shall examinethe forgery."

  "Ah!" said the judge; and _his_ face relaxed into a dry smile, while thejury broke out into unconcealed grins.

  "It was evident to me," continued Thorndyke, "that the experts would beunable to distinguish the real from the forged thumb-prints, and, thatbeing so, that they would look for some collateral evidence to guidethem. I, therefore, supplied that collateral evidence. Now, if tenprints are taken, without special precautions, from a single finger, itwill probably happen that no two of them are exactly alike; for thefinger being a rounded object of which only a small part touches thepaper, the impressions produced will show little variations according tothe part of the finger by which the print is made. But a stamp such as Ihave used has a flat surface like that of a printer's type, and, like atype, it always prints the same impression. It does not reproduce thefinger-tip, but a particular print of the finger, and so, if ten printsare made with a single stamp, each print will be a mechanical repetitionof the other nine. Thus, on a sheet bearing twenty finger-prints, ofwhich ten were forgeries made with a single stamp, it would be easy topick out the ten forged prints by the fact that they would all bemechanical repetitions of one another; while the genuine prints could bedistinguished by the fact of their presenting trifling variations in theposition of the finger.

  "Anticipating this line of reasoning, I was careful to make each printwith a different stamp and each stamp was made from a differentthumb-print, and I further selected thumb-prints which varied as widelyas possible when I made the stamps. Moreover, when I made the realthumb-prints, I was careful to put the thumb down in the same positioneach time as far as I was able; and so it happened that, on the sheetsubmitted to the experts, the real thumb-prints were nearly all alike,while the forgeries presented considerable variations. The instances inwhich the witnesses were quite certain were those in which I succeededin making the genuine prints repeat one another, and the doubtful caseswere those in which I partially failed."

  "Thank you, that is quite clear," said the judge, with a smile of deepcontent, such as is apt to appear on the judicial countenance when anexpert witness is knocked off his pedestal. "We may now proceed, Mr.Anstey."

  "You have told us," resumed Anstey, "and have submitted proofs, that itis possible to forge a thumb-print so that detection is impossible. Youhave also stated that the thumb-print on the paper found in Mr. Hornby'ssafe is a forgery. Do you mean that it _m
ay_ be a forgery, or that itactually is one?"

  "I mean that it actually is a forgery."

  "When did you first come to the conclusion that it was a forgery?"

  "When I saw it at Scotland Yard. There are three facts which suggestedthis conclusion. In the first place the print was obviously producedwith liquid blood, and yet it was a beautifully clear and distinctimpression. But such an impression could not be produced with liquidblood without the use of a slab and roller, even if great care wereused, and still less could it have been produced by an accidental smear.

  "In the second place, on measuring the print with a micrometer, I foundthat it did not agree in dimensions with a genuine thumb-print of ReubenHornby. It was appreciably larger. I photographed the print with themicrometer in contact and on comparing this with a genuine thumb-print,also photographed with the same micrometer in contact, I found that thesuspected print was larger by the fortieth of an inch, from one givenpoint on the ridge-pattern to another given point. I have hereenlargements of the two photographs in which the disagreement in size isclearly shown by the lines of the micrometer. I have also the micrometeritself and a portable microscope, if the Court wishes to verify thephotographs."

  "Thank you," said the judge, with a bland smile; "we will accept yoursworn testimony unless the learned counsel for the prosecution demandsverification."

  He received the photographs which Thorndyke handed up and, havingexamined them with close attention, passed them on to the jury.

  "The third fact," resumed Thorndyke, "is of much more importance, sinceit not only proves the print to be a forgery, but also furnishes a verydistinct clue to the origin of the forgery, and so to the identity ofthe forger." (Here the court became hushed until the silence was soprofound that the ticking of the clock seemed a sensible interruption. Iglanced at Walter, who sat motionless and rigid at the end of the bench,and perceived that a horrible pallor had spread over his face, while hisforehead was covered with beads of perspiration.) "On looking at theprint closely, I noticed at one part a minute white mark or space. Itwas of the shape of a capital S and had evidently been produced by adefect in the paper--a loose fibre which had stuck to the thumb and beendetached by it from the paper, leaving a blank space where it had been.But, on examining the paper under a low power of the microscope, I foundthe surface to be perfect and intact. No loose fibre had been detachedfrom it, for if it had, the broken end or, at least, the groove in whichit had lain, would have been visible. The inference seemed to be thatthe loose fibre had existed, not in the paper which was found in thesafe, but in the paper on which the original thumb-mark had been made.Now, as far as I knew, there was only one undoubted thumb-print ofReuben Hornby's in existence--the one in the 'Thumbograph.' At myrequest, the 'Thumbograph' was brought to my chambers by Mrs. Hornby,and, on examining the print of Reuben Hornby's left thumb, I perceivedon it a minute, S-shaped white space occupying a similar position tothat in the red thumb-mark; and when I looked at it through a powerfullens, I could clearly see the little groove in the paper in which thefibre had lain and from which it had been lifted by the inked thumb. Isubsequently made a systematic comparison of the marks in the twothumb-prints; I found that the dimensions of the mark wereproportionally the same in each--that is to say, the mark in the'Thumbograph' print had an extreme length of 26/1000 of an inch and anextreme breadth of 14.5/1000 of an inch, while that in the redthumb-mark was one-fortieth larger in each dimension, having an extremelength of 26.65/1000 of an inch and an extreme breadth of 14.86/1000 ofan inch; that the shape was identical, as was shown by superimposingtracings of greatly enlarged photographs of each mark on similarenlargements of the other; and that the mark intersected the ridges ofthe thumb-print in the same manner and at exactly the same parts in thetwo prints."

  "Do you say that--having regard to the facts which you have stated--itis certain that the red thumb-mark is a forgery?"

  "I do; and I also say that it is certain that the forgery was executedby means of the 'Thumbograph.'"

  "Might not the resemblances be merely a coincidence?"

  "No. By the law of probabilities which Mr. Singleton explained soclearly in his evidence, the adverse chances would run into untoldmillions. Here are two thumb-prints made in different places and atdifferent times--an interval of many weeks intervening. Each of thembears an accidental mark which is due not to any peculiarity of thethumb, but to a peculiarity of the paper. On the theory of coincidencesit is necessary to suppose that each piece of paper had a loose fibre ofexactly identical shape and size and that this fibre came, by accident,in contact with the thumb at exactly the same spot. But such asupposition would be more opposed to probabilities even than thesupposition that two exactly similar thumb-prints should have been madeby different persons. And then there is the further fact that the paperfound in the safe had no loose fibre to account for the mark."

  "What is your explanation of the presence of defibrinated blood in thesafe?"

  "It was probably used by the forger in making the thumb-print, for whichpurpose fresh blood would be less suitable by reason of its clotting. Hewould probably have carried a small quantity in a bottle, together withthe pocket slab and roller invented by Mr. Galton. It would thus bepossible for him to put a drop on the slab, roll it out into a thin filmand take a clean impression with his stamp. It must be remembered thatthese precautions were quite necessary, since he had to make arecognisable print at the first attempt. A failure and a second trialwould have destroyed the accidental appearance, and might have arousedsuspicion."

  "You have made some enlarged photographs of the thumb-prints, have younot?"

  "Yes. I have here two enlarged photographs, one of the 'Thumbograph'print and one of the red thumb-print. They both show the white mark veryclearly and will assist comparison of the originals, in which the markis plainly visible through a lens."

  He handed the two photographs up to the judge, together with the'Thumbograph,' the memorandum slip, and a powerful doublet lens withwhich to examine them.

  The judge inspected the two original documents with the aid of the lensand compared them with the photographs, nodding approvingly as he madeout the points of agreement. Then he passed them on to the jury and madean entry in his notes.

  While this was going on my attention was attracted by Walter Hornby. Anexpression of terror and wild despair had settled on his face, which wasghastly in its pallor and bedewed with sweat. He looked furtively atThorndyke and, as I noted the murderous hate in his eyes, I recalled ourmidnight adventure in John Street and the mysterious cigar.

  Suddenly he rose to his feet, wiping his brow and steadying himselfagainst the bench with a shaking hand; then he walked quietly to thedoor and went out. Apparently, I was not the only onlooker who had beeninterested in his doings, for, as the door swung to after him,Superintendent Miller rose from his seat and went out by the other door.

  "Are you cross-examining this witness?" the judge inquired, glancing atSir Hector Trumpler.

  "No, my lord," was the reply.

  "Are you calling any more witnesses, Mr. Anstey?"

  "Only one, my lord," replied Anstey--"the prisoner, whom I shall put inthe witness-box, as a matter of form, in order that he may make astatement on oath."

  Reuben was accordingly conducted from the dock to the witness-box, and,having been sworn, made a solemn declaration of his innocence. A briefcross-examination followed, in which nothing was elicited, but thatReuben had spent the evening at his club and gone home to his roomsabout half-past eleven and had let himself in with his latchkey. SirHector at length sat down; the prisoner was led back to the dock, andthe Court settled itself to listen to the speeches of the counsel.

  "My lord and gentlemen of the jury," Anstey commenced in his clear,mellow tones, "I do not propose to occupy your time with a long speech.The evidence that has been laid before you is at once so intelligible,so lucid, and so conclusive, that you will, no doubt, arrive at yourverdict uninfluenced by any display of rhetoric either on my pa
rt or onthe part of the learned counsel for the prosecution.

  "Nevertheless, it is desirable to disentangle from the mass of evidencethose facts which are really vital and crucial.

  "Now the one fact which stands out and dominates the whole case is this:The prisoner's connection with this case rests solely upon the policetheory of the infallibility of finger-prints. Apart from the evidence ofthe thumb-print there is not, and there never was, the faintest breathof suspicion against him. You have heard him described as a man ofunsullied honour, as a man whose character is above reproach; a man whois trusted implicitly by those who have had dealings with him. And thischaracter was not given by a casual stranger, but by one who has knownhim from childhood. His record is an unbroken record of honourableconduct; his life has been that of a clean-living, straightforwardgentleman. And now he stands before you charged with a miserable, paltrytheft; charged with having robbed that generous friend, the brother ofhis own father, the guardian of his childhood and the benefactor who hasplanned and striven for his well-being; charged, in short, gentlemen,with a crime which every circumstance connected with him and every traitof his known character renders utterly inconceivable. Now upon whatgrounds has this gentleman of irreproachable character been charged withthis mean and sordid crime? Baldly stated, the grounds of the accusationare these: A certain learned and eminent man of science has made astatement, which the police have not merely accepted but have, inpractice, extended beyond its original meaning. That statement is asfollows: 'A complete, or nearly complete, accordance between two printsof a single finger ... affords evidence requiring no corroboration, thatthe persons from whom they were made are the same.'

  "That statement, gentlemen, is in the highest degree misleading, andought not to have been made without due warning and qualification. Sofar is it from being true, in practice, that its exact contrary is thefact; the evidence of a finger-print, in the absence of corroboration,is absolutely worthless. Of all forms of forgery, the forgery of afinger-print is the easiest and most secure, as you have seen in thiscourt to-day. Consider the character of the high-class forger--hisskill, his ingenuity, his resource. Think of the forged banknotes, ofwhich not only the engraving, the design and the signature, but even thevery paper with its private watermarks, is imitated with a perfectionthat is at once the admiration and the despair of those who have todistinguish the true from the false; think of the forged cheque, inwhich actual perforations are filled up, of which portions are cut outbodily and replaced by indistinguishable patches; think of these, andthen of a finger-print, of which any photo-engraver's apprentice canmake you a forgery that the greatest experts cannot distinguish from theoriginal, which any capable amateur can imitate beyond detection after amonth's practice; and then ask yourselves if this is the kind ofevidence on which, without any support or corroboration, a gentleman ofhonour and position should be dragged before a criminal court andcharged with having committed a crime of the basest and most sordidtype. "But I must not detain you with unnecessary appeals. I willremind you briefly of the salient facts. The case for the prosecutionrests upon the assertion that the thumb-print found in the safe was madeby the thumb of the prisoner. If that thumb-print was not made by theprisoner, there is not only no case against him but no suspicion of anykind.

  "Now, was that thumb-print made by the prisoner's thumb? You have hadconclusive evidence that it was not. That thumb-print differed in thesize, or scale, of the pattern from a genuine thumb-print of theprisoner's. The difference was small, but it was fatal to the policetheory; the two prints were not identical.

  "But, if not the prisoner's thumb-print, what was it? The resemblance ofthe pattern was too exact for it to be the thumb-print of anotherperson, for it reproduced not only the pattern of the ridges on theprisoner's thumb, but also the scar of an old wound. The answer that Ipropose to this question is, that it was an intentional imitation of theprisoner's thumb-print, made with the purpose of fixing suspicion on theprisoner, and so ensuring the safety of the actual criminal. Are thereany facts which support this theory? Yes, there are several facts whichsupport it very strongly.

  "First, there are the facts that I have just mentioned. The redthumb-print disagreed with the genuine print in its scale or dimensions.It was not the prisoner's thumb-print; but neither was it that of anyother person. The only alternative is that it was a forgery.

  "In the second place, that print was evidently made with the aid ofcertain appliances and materials, and one of those materials, namelydefibrinated blood, was found in the safe.

  "In the third place, there is the coincidence that the print was onewhich it was possible to forge. The prisoner has ten digits--eightfingers and two thumbs. But there were in existence actual prints of thetwo thumbs, whereas no prints of the fingers were in existence; hence itwould have been impossible to forge a print of any of the fingers. So ithappens that the red thumb-print resembled one of the two prints ofwhich forgery was possible.

  "In the fourth place, the red thumb-print reproduces an accidentalpeculiarity of the 'Thumbograph' print. Now, if the red thumb-print is aforgery, it must have been made from the 'Thumbograph' print, sincethere exists no other print from which it could have been made. Hence wehave the striking fact that the red thumb-print is an exactreplica--including accidental peculiarities--of the only print fromwhich a forgery could have been made. The accidental S-shaped mark inthe 'Thumbograph' print is accounted for by the condition of the paper;the occurrence of this mark in the red thumb-print is not accounted forby any peculiarity of the paper, and can be accounted for in no way,excepting by assuming the one to be a copy of the other. The conclusionis thus inevitable that the red thumb-print is a photo-mechanicalreproduction of the 'Thumbograph' print.

  "But there is yet another point. If the red thumb-print is a forgeryreproduced from the 'Thumbograph' print, the forger must at some timehave had access to the 'Thumbograph.' Now, you have heard Mrs. Hornby'sremarkable story of the mysterious disappearance of the 'Thumbograph'and its still more mysterious reappearance. That story can have left nodoubt in your minds that some person had surreptitiously removed the'Thumbograph' and, after an unknown interval, secretly replaced it. Thusthe theory of forgery receives confirmation at every point, and is inagreement with every known fact; whereas the theory that the redthumb-print was a genuine thumb-print, is based upon a gratuitousassumption, and has not had a single fact advanced in its support.

  "Accordingly, gentlemen, I assert that the prisoner's innocence has beenproved in the most complete and convincing manner, and I ask you for averdict in accordance with that proof."

  As Anstey resumed his seat, a low rumble of applause was heard from thegallery. It subsided instantly on a gesture of disapproval from thejudge, and a silence fell upon the court, in which the clock, withcynical indifference, continued to record in its brusque monotone thepassage of the fleeting seconds.

  "He is saved, Dr. Jervis! Oh! surely he is saved!" Juliet exclaimed inan agitated whisper. "They must see that he is innocent now."

  "Have patience a little longer," I answered. "It will soon be over now."

  Sir Hector Trumpler was already on his feet and, after bestowing on thejury a stern hypnotic stare, he plunged into his reply with a reallyadmirable air of conviction and sincerity. "My lord and gentlemen ofthe jury: The case which is now before this Court is one, as I havealready remarked, in which human nature is presented in a highlyunfavourable light. But I need not insist upon this aspect of the case,which will already, no doubt, have impressed you sufficiently. It isnecessary merely for me, as my learned friend has aptly expressed it, todisentangle the actual facts of the case from the web of casuistry thathas been woven around them.

  "Those facts are of extreme simplicity. A safe has been opened andproperty of great value abstracted from it. It has been opened by meansof false keys. Now there are two men who have, from time to time, hadpossession of the true keys, and thus had the opportunity of makingcopies of them. When the safe is opened by its rightful o
wner, theproperty is gone, and there is found the print of the thumb of one ofthese two men. That thumb-print was not there when the safe was closed.The man whose thumb-print is found is a left-handed man; the print isthe print of a left thumb. It would seem, gentlemen, as if theconclusion were so obvious that no sane person could be found to contestit; and I submit that the conclusion which any sane person would arriveat--the only possible conclusion--is, that the person whose thumb-printwas found in the safe is the person who stole the property from thesafe. But the thumb-print was, admittedly, that of the prisoner at thebar, and therefore the prisoner at the bar is the person who stole thediamonds from the safe.

  "It is true that certain fantastic attempts have been made to explainaway these obvious facts. Certain far-fetched scientific theories havebeen propounded and an exhibition of legerdemain has taken place which,I venture to think, would have been more appropriate to some place ofpublic entertainment than to a court of justice. That exhibition has, nodoubt, afforded you considerable amusement. It has furnished a pleasingrelaxation from the serious business of the court. It has even beeninstructive, as showing to what extent it is possible for plain facts tobe perverted by misdirected ingenuity. But unless you are prepared toconsider this crime as an elaborate hoax--as a practical joke carriedout by a facetious criminal of extraordinary knowledge, skill andgeneral attainments--you must, after all, come to the only conclusionthat the facts justify: that the safe was opened and the propertyabstracted by the prisoner. Accordingly, gentlemen, I ask you, havingregard to your important position as the guardians of the well-being andsecurity of your fellow-citizens, to give your verdict in accordancewith the evidence, as you have solemnly sworn to do; which verdict, Isubmit, can be no other than that the prisoner is guilty of the crimewith which he is charged."

  Sir Hector sat down, and the jury, who had listened to his speech withsolid attention, gazed expectantly at the judge, as though they shouldsay: "Now, which of these two are we to believe?"

  The judge turned over his notes with an air of quiet composure, writingdown a word here and there as he compared the various points in theevidence. Then he turned to the jury with a manner at once persuasiveand confidential--

  "It is not necessary, gentlemen," he commenced, "for me to occupy yourtime with an exhaustive analysis of the evidence. That evidence youyourselves have heard, and it has been given, for the most part, withadmirable clearness. Moreover, the learned counsel for the defence hascollated and compared that evidence so lucidly, and, I may say, soimpartially, that a detailed repetition on my part would besuperfluous. I shall therefore confine myself to a few comments whichmay help you in the consideration of your verdict.

  "I need hardly point out to you that the reference made by the learnedcounsel for the prosecution to far-fetched scientific theories issomewhat misleading. The only evidence of a theoretical character wasthat of the finger-print experts. The evidence of Dr. Rowe and of Dr.Thorndyke dealt exclusively with matters of fact. Such inferences aswere drawn by them were accompanied by statements of the facts whichyielded such inferences.

  "Now, an examination of the evidence which you have heard shows, as thelearned counsel for the defence has justly observed, that the entirecase resolves itself into a single question, which is this: 'Was thethumb-print that was found in Mr. Hornby's safe made by the thumb of theprisoner, or was it not?' If that thumb-print was made by the prisoner'sthumb, then the prisoner must, at least, have been present when the safewas unlawfully opened. If that thumb-print was not made by theprisoner's thumb, there is nothing to connect him with the crime. Thequestion is one of fact upon which it will be your duty to decide; and Imust remind you, gentlemen, that you are the sole judges of the facts ofthe case, and that you are to consider any remarks of mine as merelysuggestions which you are to entertain or to disregard according to yourjudgement.

  "Now let us consider this question by the light of the evidence. Thisthumb-print was either made by the prisoner or it was not. What evidencehas been brought forward to show that it was made by the prisoner? Well,there is the evidence of the ridge-pattern. That pattern is identicalwith the pattern of the prisoner's thumb-print, and even has theimpression of a scar which crosses the pattern in a particular mannerin the prisoner's thumb-print. There is no need to enter into theelaborate calculations as to the chances of agreement; the practicalfact, which is not disputed, is that if this red thumb-print is agenuine thumb-print at all, it was made by the prisoner's thumb. But itis contended that it is not a genuine thumb-print; that it is amechanical imitation--in fact a forgery.

  "The more general question thus becomes narrowed down to the moreparticular question: 'Is this a genuine thumb-print or is it a forgery?'Let us consider the evidence. First, what evidence is there that it is agenuine thumb-print? There is none. The identity of the pattern is noevidence on this point, because a forgery would also exhibit identity ofpattern. The genuineness of the thumb-print was assumed by theprosecution, and no evidence has been offered.

  "But now what evidence is there that the red thumb-print is a forgery?

  "First, there is the question of size. Two different-sized prints couldhardly be made by the same thumb. Then there is the evidence of the useof appliances. Safe-robbers do not ordinarily provide themselves withinking-slabs and rollers with which to make distinct impressions oftheir own fingers. Then there is the accidental mark on the print whichalso exists on the only genuine print that could have been used for thepurpose of forgery, which is easily explained on the theory of aforgery, but which is otherwise totally incomprehensible. Finally, thereis the strange disappearance of the 'Thumbograph' and its strangereappearance. All this is striking and weighty evidence, to which mustbe added that adduced by Dr. Thorndyke as showing how perfectly it ispossible to imitate a finger-print.

  "These are the main facts of the case, and it is for you to considerthem. If, on careful consideration, you decide that the red thumb-printwas actually made by the prisoner's thumb, then it will be your duty topronounce the prisoner guilty; but if, on weighing the evidence, youdecide that the thumb-print is a forgery, then it will be your duty topronounce the prisoner not guilty. It is now past the usual luncheonhour, and, if you desire it, you can retire to consider your verdictwhile the Court adjourns."

  The jurymen whispered together for a few moments and then the foremanstood up.

  "We have agreed on our verdict, my lord," he said.

  The prisoner, who had just been led to the back of the dock, was nowbrought back to the bar. The grey-wigged clerk of the court stood up andaddressed the jury.

  "Are you all agreed upon your verdict, gentlemen?"

  "We are," replied the foreman.

  "What do you say, gentlemen? Is the prisoner guilty or not guilty?"

  "Not guilty," replied the foreman, raising his voice and glancing atReuben.

  A storm of applause burst from the gallery and was, for the moment,disregarded by the judge. Mrs. Hornby laughed aloud--a strange,unnatural laugh--and then crammed her handkerchief into her mouth, andso sat gazing at Reuben with the tears coursing down her face, whileJuliet laid her head upon the desk and sobbed silently.

  After a brief space the judge raised an admonitory hand, and, when thecommotion had subsided, addressed the prisoner, who stood at the bar,calm and self-possessed, though his face bore a slight flush--

  "Reuben Hornby, the jury, after duly weighing the evidence in this case,have found you to be not guilty of the crime with which you werecharged. With that verdict I most heartily agree. In view of theevidence which has been given, I consider that no other verdict waspossible, and I venture to say that you leave this court with yourinnocence fully established, and without a stain upon your character. Inthe distress which you have recently suffered, as well as in yourrejoicing at the verdict of the jury, you have the sympathy of theCourt, and of everyone present, and that sympathy will not be diminishedby the consideration that, with a less capable defence, the result mighthave been very different.


  "I desire to express my admiration at the manner in which that defencewas conducted, and I desire especially to observe that not you alone,but the public at large, are deeply indebted to Dr. Thorndyke, who, byhis insight, his knowledge and his ingenuity, has probably averted avery serious miscarriage of justice. The Court will now adjourn untilhalf-past two."

  The judge rose from his seat and everyone present stood up; and, amidstthe clamour of many feet upon the gallery stairs, the door of the dockwas thrown open by a smiling police officer and Reuben came down thestairs into the body of the court.