The Red Thumb Mark

by R. Austin Freeman

  CHAPTER VIII

  A SUSPICIOUS ACCIDENT

  The Temple clock had announced in soft and confidential tones that itwas a quarter to seven, in which statement it was stoutly supported byits colleague on our mantelpiece, and still there was no sign ofThorndyke. It was really a little strange, for he was the soul ofpunctuality, and moreover, his engagements were of such a kind asrendered punctuality possible. I was burning with impatience to impartmy news to him, and this fact, together with the ghostly proceedings ofPolton, worked me up to a state of nervous tension that rendered eitherrest or thought equally impossible. I looked out of the window at thelamp below, glaring redly through the fog, and then, opening the door,went out on to the landing to listen.

  At this moment Polton made a silent appearance on the stairs leadingfrom the laboratory, giving me quite a start; and I was about to retireinto the room when my ear caught the tinkle of a hansom approaching fromPaper Buildings.

  The vehicle drew nearer, and at length stopped opposite the house, onwhich Polton slid down the stairs with the agility of a harlequin. A fewmoments later I heard his voice ascending from the hall--

  "I do hope, sir, you're not much hurt?"

  I ran down the stairs and met Thorndyke coming up slowly with his righthand on Polton's shoulder. His clothes were muddy, his left arm was in asling, and a black handkerchief under his hat evidently concealed abandage.

  "I am not really hurt at all," Thorndyke replied cheerily, "though verydisreputable to look at. Just came a cropper in the mud, Jervis," headded, as he noted my dismayed expression. "Dinner and a clothes-brushare what I chiefly need." Nevertheless, he looked very pale and shakenwhen he came into the light on the landing, and he sank into hiseasy-chair in the limp manner of a man either very weak or veryfatigued.

  "How did it happen?" I asked when Polton had crept away on tip-toe tomake ready for dinner.

  Thorndyke looked round to make sure that his henchman had departed, andsaid--

  "A queer affair, Jervis; a very odd affair indeed. I was coming up fromthe Borough, picking my way mighty carefully across the road on accountof the greasy, slippery mud, and had just reached the foot of LondonBridge when I heard a heavy lorry coming down the slope a good deal toofast, considering that it was impossible to see more than a dozen yardsahead, and I stopped on the kerb to see it safely past. Just as thehorses emerged from the fog, a man came up behind and lurched violentlyagainst me and, strangely enough, at the same moment passed his foot infront of mine. Of course I went sprawling into the road right in frontof the lorry. The horses came stamping and sliding straight on to me,and, before I could wriggle out of the way, the hoof of one of themsmashed in my hat--that was a new one that I came home in--andhalf-stunned me. Then the near wheel struck my head, making a dirtylittle scalp wound, and pinned down my sleeve so that I couldn't pullaway my arm, which is consequently barked all the way down. It was amighty near thing, Jervis; another inch or two and I should have beenrolled out as flat as a starfish."

  "What became of the man?" I asked, wishing I could have had a briefinterview with him.

  "Lost to sight though to memory dear: he was off like a lamplighter. Analcoholic apple-woman picked me up and escorted me back to the hospital.It must have been a touching spectacle," he added, with a dry smile atthe recollection.

  "And I suppose they kept you there for a time to recover?"

  "Yes; I went into dry dock in the O. P. room, and then old Langdaleinsisted on my lying down for an hour or so in case any symptoms ofconcussion should appear. But I was only a trifle shaken and confused.Still, it was a queer affair."

  "You mean the man pushing you down in that way?"

  "Yes; I can't make out how his foot got in front of mine."

  "You don't think it was intentional, surely?" I said.

  "No, of course not," he replied, but without much conviction, as itseemed to me; and I was about to pursue the matter when Poltonreappeared, and my friend abruptly changed the subject.

  After dinner I recounted my conversation with Walter Hornby, watching mycolleague's face with some eagerness to see what effect this newinformation would produce on him. The result was, on the whole,disappointing. He was interested, keenly interested, but showed nosymptoms of excitement.

  "So John Hornby has been plunging in mines, eh?" he said, when I hadfinished. "He ought to know better at his age. Did you learn how long hehad been in difficulties?"

  "No. But it can hardly have been quite sudden and unforeseen."

  "I should think not," Thorndyke agreed. "A sudden slump often provesdisastrous to the regular Stock Exchange gambler who is payingdifferences on large quantities of unpaid-for stock. But it looks as ifHornby had actually bought and paid for these mines, treating them asinvestments rather than speculations, in which case the depreciationwould not have affected him in the same way. It would be interesting toknow for certain."

  "It might have a considerable bearing on the present case, might itnot?"

  "Undoubtedly," said Thorndyke. "It might bear on the case in more waysthan one. But you have some special point in your mind, I think."

  "Yes. I was thinking that if these embarrassments had been growing upgradually for some time, they might have already assumed an acute format the time of the robbery."

  "That is well considered," said my colleague. "But what is the specialbearing on the case supposing it was so?"

  "On the supposition," I replied, "that Mr. Hornby was in actualpecuniary difficulties at the date of the robbery, it seems to mepossible to construct a hypothesis as to the identity of the robber."

  "I should like to hear that hypothesis stated," said Thorndyke, rousinghimself and regarding me with lively interest.

  "It is a highly improbable one," I began with some natural shyness atthe idea of airing my wits before this master of inductive method; "infact, it is almost fantastic."

  "Never mind that," said he. "A sound thinker gives equal considerationto the probable and the improbable."

  Thus encouraged, I proceeded to set forth the theory of the crime as ithad occurred to me on my way home in the fog, and I was gratified toobserve the close attention with which Thorndyke listened, and hislittle nods of approval at each point that I made.

  When I had finished, he remained silent for some time, lookingthoughtfully into the fire and evidently considering how my theory andthe new facts on which it was based would fit in with the rest of thedata. At length he spoke, without, however, removing his eyes from thered embers--

  "This theory of yours, Jervis, does great credit to your ingenuity. Wemay disregard the improbability, seeing that the alternative theoriesare almost equally improbable, and the fact that emerges, and thatgratifies me more than I can tell you, is that you are gifted withenough scientific imagination to construct a possible train of events.Indeed, the improbability--combined, of course, with possibility--reallyadds to the achievement, for the dullest mind can perceive theobvious--as, for instance, the importance of a finger-print. You havereally done a great thing, and I congratulate you; for you haveemancipated yourself, at least to some extent, from the greatfinger-print obsession, which has possessed the legal mind ever sinceGalton published his epoch-making monograph. In that work I remember hestates that a finger-print affords evidence requiring nocorroboration--a most dangerous and misleading statement which has beenfastened upon eagerly by the police, who have naturally been delightedat obtaining a sort of magic touchstone by which they are saved thelabour of investigation. But there is no such thing as a single factthat 'affords evidence requiring no corroboration.' As well might oneexpect to make a syllogism with a single premise." "I suppose theywould hardly go so far as that," I said, laughing.

  "No," he admitted. "But the kind of syllogism that they do make isthis--

  "'The crime was committed by the person who made this finger-print.

  "'But John Smith is the person who made the finger-print.

  "'Therefore the crime was committed by John Smith.'"
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  "Well, that is a perfectly good syllogism, isn't it?" I asked.

  "Perfectly," he replied. "But, you see, it begs the whole question,which is, 'Was the crime committed by the person who made thisfinger-print?' That is where the corroboration is required."

  "That practically leaves the case to be investigated without referenceto the finger-print, which thus becomes of no importance."

  "Not at all," rejoined Thorndyke; "the finger-print is a most valuableclue as long as its evidential value is not exaggerated. Take ourpresent case, for instance. Without the thumb-print, the robbery mighthave been committed by anybody; there is no clue whatever. But theexistence of the thumb-print narrows the inquiry down to Reuben or someperson having access to his finger-prints."

  "Yes, I see. Then you consider my theory of John Hornby as theperpetrator of the robbery as quite a tenable one?" "Quite," repliedThorndyke. "I have entertained it from the first; and the new facts thatyou have gathered increase its probability. You remember I said thatfour hypotheses were possible: that the robbery was committed either byReuben, by Walter, by John Hornby, or by some other person. Now, puttingaside the 'some other person' for consideration only if the first threehypotheses fail, we have left, Reuben, Walter, and John. But if we leavethe thumb-print out of the question, the probabilities evidently pointto John Hornby, since he, admittedly, had access to the diamonds,whereas there is nothing to show that the others had. The thumb-print,however, transfers the suspicion to Reuben; but yet, as your theorymakes evident, it does not completely clear John Hornby. As the casestands, the balance of probabilities may be stated thus: John Hornbyundoubtedly had access to the diamonds, and therefore might have stolenthem. But if the thumb-mark was made after he closed the safe and beforehe opened it again, some other person must have had access to them, andwas probably the thief.

  "The thumb-mark is that of Reuben Hornby, a fact that establishes a_prima facie_ probability that he stole the diamonds. But there is noevidence that he had access to them, and if he had not, he could nothave made the thumb-mark in the manner and at the time stated.

  "But John Hornby may have had access to the previously-made thumb-markof Reuben, and may possibly have obtained it; in which case he is almostcertainly the thief.

  "As to Walter Hornby, he may have had the means of obtaining Reuben'sthumb-mark; but there is no evidence that he had access either to thediamonds or to Mr. Hornby's memorandum block. The _prima facie_probabilities in his case, therefore, are very slight."

  "The actual points at issue, then," I said, "are, whether Reuben had anymeans of opening the safe, and whether Mr. Hornby ever did actually havethe opportunity of obtaining Reuben's thumb-mark in blood on hismemorandum block."

  "Yes," replied Thorndyke. "Those are the points--with some others--andthey are likely to remain unsettled. Reuben's rooms have been searchedby the police, who failed to find any skeleton or duplicate keys; butthis proves nothing, as he would probably have made away with them whenhe heard of the thumb-mark being found. As to the other matter, I haveasked Reuben, and he has no recollection of ever having made athumb-mark in blood. So there the matter rests."

  "And what about Mr. Hornby's liability for the diamonds?"

  "I think we may dismiss that," answered Thorndyke. "He had undertaken noliability and there was no negligence. He would not be liable at law."

  After my colleague retired, which he did quite early, I sat for a longtime pondering upon this singular case in which I found myself involved.And the more I thought about it the more puzzled I became. If Thorndykehad no more satisfactory explanation to offer than that which he hadgiven me this evening, the defence was hopeless, for the court was notlikely to accept his estimate of the evidential value of finger-prints.Yet he had given Reuben something like a positive assurance that therewould be an adequate defence, and had expressed his own positiveconviction of the accused man's innocence. But Thorndyke was not a manto reach such a conviction through merely sentimental considerations.The inevitable conclusion was that he had something up his sleeve--thathe had gained possession of some facts that had escaped my observation;and when I had reached this point I knocked out my pipe and betookmyself to bed.