VII

  THE DUPLICATE HARLEQUIN

  One day about two weeks after the unravelling of the mystery of the opallost on board the yacht _Idler_, Mr. Barnes called upon Mr. Mitchel andwas cordially received.

  "Glad to see you, Mr. Barnes. Anything stirring in the realm of crime?"

  "'Stirring' would be a fitting adjective, I think, Mr. Mitchel. Eversince the _Idler_ affair I have occupied myself with a study of theproblem, which I am convinced we have but partially solved. You mayrecall that you gave me a clue."

  "You mean that Livingstone, when he gave me the opal, remarked, 'Womenare poor conspirators.' Yes, I remember calling your attention to that.Has your clue led to any solution?"

  "Oh, I am not out of the maze yet; more likely just entering the mostintricate depths. Still, I flatter myself that I have accomplishedsomething; enough to satisfy me that 'mischief is brewing,' and that theconspirators are still conspiring. Moreover, there is little doubt thatyou are deeply concerned in the new plot."

  "What! You insinuate that I am in this conspiracy?"

  "Only as a possible victim. You are the object of the plot."

  "Perhaps you think that I am in danger?" Mr. Mitchel smiled as thoughthe idea of danger were a pleasurable one.

  "Were you any other man than yourself, I should say most decidedly thatyou are in danger."

  "But, being myself, you fancy that the danger will pass from me?"

  "Being yourself, I anticipate that you will compel the danger to passfrom you."

  "Mr. Barnes, you flatter me. Perhaps I may be able to thwart theconspirators, now that you warn me; if I do, however, I must admit mygreat indebtedness to you. To be forewarned is to have the fight halfwon, and I candidly say that I was entirely unsuspicious of any lurkingdanger."

  "Exactly. With all your acumen, I was sure that your suspicions had notbeen aroused. The conspirators are wary, and, I assure you, unusuallyskilful. So, under all the circumstances, I felt it my duty to be on thealert."

  "Ah, I see," said Mr. Mitchel, in that tone peculiar to him, which madeit doubtful whether he spoke in earnest, or whether his words hid keensatire. "The old cat being asleep, the kitten watches. That is very niceof you. Really, it is quite a comforting thought that so skilful adetective is ever guarding my person. Especially as I am the owner ofso many gems to which the covetous must ever look longingly."

  "That is just how I reasoned it," said Mr. Barnes, eagerly, wishing tojustify his actions, which he began to suspect Mr. Mitchel might resent."You explained to me your reasons why you have purchased so manyvaluable jewels. You claimed that almost every large gem has been thecause, or rather the object, of crime. The Aztec Opal came into yourpossession under most peculiar circumstances. In fact, you thwarted acriminal just as he had come into possession of it. But this criminal isa wealthy man. Not perhaps as rich as yourself, but rich enough to beabove stealing even such a valuable bauble. It could not have been theintrinsic value of the opal which tempted him; it must have been thatsome special reason existed; some reason, I mean, for his acquiringpossession of this particular opal. All this being true, it would be anatural sequence that his efforts to get the opal would not cease merelybecause it had changed hands."

  "Your argument is most interesting, Mr. Barnes, especially as it iswithout a flaw. As you say, from all this reasoning it was a naturalsequence that Mr. Livingstone would continue his quest for the opal.This being so obvious, did you imagine that it had escaped me?"

  Mr. Barnes was confused by the question. He really admired Mr. Mitchelvery much, and though he considered him quite conceited, he alsoadmitted that he had great analytical powers and remarkable acumen. Healso, more than anything else, desired a perpetuation of his friendship;indeed, it had been with an idea of increasing the bond between themthat he had called. He had spent much of his time, time which could havebeen occupied with other matters to better financial advantage, and allwith the purpose of warding off from his friend a danger which he had atfirst considered as a distant possibility, but which later he lookedupon as certain, if nothing intervened to hinder the plot, which he knewwas rapidly approaching the moment of execution. He therefore hastenedto make further explanation:

  "Not at all--not at all. I am merely indicating the steps by which Ireached my conclusions. I am giving you my reasons for what I fear younow may consider my interference in your affairs. Yet I assure you Imeant it all----"

  "For the best. Why, of course, my friend; did you suppose that I doubtedyour good intent, merely because I spoke brusquely?" Mr. Mitchel heldout his hand cordially, and Mr. Barnes grasped it, glad to note thealtered demeanor of his companion. Mr. Mitchel continued: "Will younever learn that my weakness is for antagonizing detectives? When youcome here to tell me that you have been 'investigating' my privateaffairs, how could I resist telling you that I knew all about it, orthat I could take care of myself? I would not be Leroy Mitchel were itotherwise."

  "How do you mean that you know all about it?"

  "Well, perhaps not all. I am not exactly omniscient. Still, I knowsomething. Let me see, now. How much do I know? First, then, you havehad this Livingstone watched. Second, you have introduced one of yourspies, a young woman, into the home of Mrs. Gray. In spite of youralleged faith in Dennett Moore, you had him watched also, though foronly two or three days. Lastly, you have discovered Pedro Domingo,and----"

  "In Heaven's name, Mr. Mitchel, how do you know all this?" Mr. Barneswas utterly dumbfounded by what he had heard.

  "All this?" said Mr. Mitchel, with a suave smile; "why, I have mentionedonly four small facts."

  "Small facts?"

  "Yes, quite small. Let us run them over again. First, I stated that youhad Mr. Livingstone watched. That was not hard to know, because I alsohad a spy upon his track."

  "You?"

  "Yes, I. Why not? Did you not just now agree that it was obvious that hewould continue his efforts to get the opal? Being determined that Ishould never part with it whilst alive, it likewise followed that hemust kill me, or have me killed, in order to obtain it. Under thesecircumstances it was only common caution to have the man watched.Indeed, the method was altogether too common. It was _bizarre_. Still,my spy was no common spy. In that, at least, my method was unique.Secondly, I claimed that you had introduced a woman spy into the home ofMrs. Gray. To learn this was even easier. I deduced it from what I knowof your methods. You played the same trick on my wife once, I think youwill recall. Supposing Mrs. Gray to be a conspirator (that was yourclue, I think), you would hardly watch Livingstone and neglect thewoman. Yet the actual knowledge came to me in a very simple manner."

  "How was that?"

  "Why, Mr. Gray told me."

  "Mr. Gray told you?"

  "Mr. Gray himself. You see, your assistants are not all so clever asyourself, though I doubt not this girl may think that she is a genius.You told her to seek a position in the house, and what does she do? Shegoes straight to Mr. Gray and tells him her purpose; hints that it mightbe well for him to know just what really actuated Mrs. Gray in thecurious affair on the yacht, and agrees to 'discover everything'--thosewere her words--if he would give her the opportunity. Poor man, shefilled his mind with dire suspicions and he managed it so that she wastaken into service. Up to the present time she has discovered nothing.At least, so she tells him."

  "The little she-devil! You said that she explained her whole purpose. Doyou mean----"

  "Oh, no. She did not implicate you, nor divulge her true mission. Thefun of the thing is that she claimed to be a 'private detective' andthat this venture was entirely her own idea. In fact, she is workingfor Mr. Gray. Is not that droll?" Mr. Mitchel threw back his head andlaughed heartily. Mr. Barnes did not quite see the fun, and looked grim.All he said was:

  "She acted beyond her instructions, yet it seems that she has not doneany harm; and though she is like an untamed colt, apt to take the bitbetween her teeth, still she is shrewd. But I'l
l curb her yet. Now as toyour third fact. How did you know that I had Mr. Moore watched, and onlyfor two or three days?"

  "Why, I recognized one of your spies following him one day downBroadway, and as Moore sailed for Europe two days after, I made thededuction that you had withdrawn your watch-dog."

  "Well, then," said Mr. Barnes, testily, "how did you know that I had, asyou declare, 'discovered Pedro Domingo'?"

  "How did I know that? Why--but that can wait. You certainly did not callthis morning to ask me all these questions. You came, as I presume, toconvey information."

  "Oh, you know so much, it is evidently unnecessary for me to tell you ofmy trifling discoveries." Mr. Barnes was suffering from wounded pride.

  "Come, come," exclaimed Mr. Mitchel, cheerily, "be a man; don't bedowncast and fall into the dumps merely because I surprised a fewtrifling facts in your game, and could not resist the fun of guying youa little. You see, I still admit that what I know are but triflingfacts; what you know, on the contrary, is perhaps of great importance.Indeed, I am assured that without your information, without a fullknowledge of all that you have discovered, my own plans may go awry, andthen the danger at which you hint might be all too real. Do you not seethat, knowing that you are interested in this case, I have been only toowilling to let half the burden of the investigation fall upon you? Thatto your skill I have intrusted all of that work which I knew you coulddo so well? That in the most literal sense we have been silent partners,and that I depended upon your friendship to bring you to me with yournews, just as it has brought you?"

  This speech entirely mollified Mr. Barnes, and, with a brighteningcountenance, he exclaimed:

  "Mr. Mitchel, I'm an ass. You are right to laugh at me."

  "Nonsense! I defy all other detectives, because Mr. Barnes works withme."

  "Bosh!" said the detective, deprecatingly, but pleased nevertheless bythe words of flattery. "Well, then, suppose I tell you my story from thebeginning?"

  "From the beginning, by all means."

  "In speaking of the woman whom I set to spy upon Mrs. Gray, you just nowmentioned that I had once played the same trick upon your wife. Verytrue, and not only is this the same trick, but it is the same girl."

  "What! Lucette?"

  "The same. This is not the first time that she has chosen to resort toher own devices rather than to follow strictly the orders given to her.In this case, however, as I said before, she has done no harm, and onthe contrary, I think you would find her report, which I received anhour ago, quite interesting."

  "Ah, you have brought it with you?"

  "Yes. I will read it to you. Of course it is not addressed to me,neither is there any signature. No names are mentioned except byinitial. All this is the girl's own devising, so you see she is notentirely stupid. She writes:

  "'At last I have discovered everything.' You observe that she is notunappreciative of her own ability. 'Mr. L. was right. Women are badconspirators. At least he is right as to Mrs. G. She has dropped theconspiracy entirely, if she ever was a real conspirator, which I doubt,for, though you may not suspect it, she loves her husband. How do Iknow? Well, a woman has instincts about love. A man may swear eternaldevotion to a woman eight hours a day for a year, without convincingher, when she would detect the true lover by the way he ties hershoe-string, unasked. So here. I have not heard madame talking in hersleep, neither has she taken her maid for a confidante, though I thinkshe might find a worse adviser. Still I say she loves her husband. Howdo I know? When a woman is constantly doing things which add to thecomfort of a man, and for which she never receives thanks, because theyare such trifles, you may be sure the woman loves the man, and byhundreds of such tokens I know that Mrs. G. is in love with her husband.To reach the next point I must give you an axiom. A woman never lovesmore than one man at a time. She may have many lovers in the course of alifetime, but in each instance she imagines that all previous affairswere delusions, and that at last the divine fire consumes her. To thislast love she is constant until he proves unworthy, and ofttimes evenafter. No, a man may be able to love two persons, but a woman'saffections are ever centred in a single idol. From which it is a logicaldeduction that Mrs. G. does not and did not love Mr. L. Then why did shegive him the opal? A question which will puzzle you, and for which youare at a loss for an answer.'"

  "She is not complimentary," interrupted Mr. Mitchel.

  "Not very," said Mr. Barnes, and then he continued reading:

  "'This is a question at which I arrived, as you see, by logical mentalstages. This is the question to which I have found the reply. This iswhat I mean when I say I have discovered all: Yesterday afternoon Mr. L.called. Madame hesitated, but finally decided to see him. From herglances in my direction, I was sure she feared I might accidentally findit convenient to be near enough to a keyhole to overhear theconversation which was about to ensue, and, as I did not wish her tomake such an "accident" impossible, I innocently suggested that if sheintended to receive a visitor, I should be glad to have permission toleave the house for an hour. The trick worked to a charm. Madame seemedonly too glad to get rid of me. I hurried downstairs into the backparlor, where, by secreting myself between the heavy portieres and theclosed folding-doors, my sharp ears readily followed the conversation,except such few passages as were spoken in very low tones, but which Iam sure were unimportant. The details I will give you when I see you.Suffice it to say that I discovered that madame's reason for refusing tolet her husband sell the jewel to that crank Mr. M. ----'"

  "Ah; I see she remembers me," said Mr. Mitchel, with a smile.

  "How could she forget your locking her in a room when she was mostanxious to be elsewhere? But let me finish this:

  "'--to that crank Mr. M. was because Mr. L. was telling her how to makea deal more money out of the jewel. It seems that he has the mate to it,and that the two were stolen from an idol somewhere in Mexico, and thata fabulous sum could be obtained by returning the two gems to the nativepriests. Just how, I do not know.'"

  "So she did not discover everything, after all," said Mr. Mitchel.

  "No; but she is right in the main. Her report continues:

  "'Madame, however, hesitated to go into the venture, partly because Mr.L. insisted that the matter be kept secret from her husband, and moreparticularly because the money in exchange was not to be forthcomingimmediately. On the yacht she changed her mind impulsively. The resultof that you know.'

  "That is all," said Mr. Barnes, folding the paper and returning it tohis pocket.

  "That is all you know?" asked Mr. Mitchel.

  "No; that is all that Lucette knows. I know how the fabulous sum ofmoney was to be had in exchange for the two opals."

  "Ah; that is more to our immediate purpose. How have you made thisdiscovery?"

  "My spies learned practically nothing by shadowing Livingstone, exceptthat he has had several meetings with a half-breed Mexican who callshimself Pedro Domingo. I decided that it would be best for me tointerview Senor Domingo myself, rather than to entrust him to a secondman."

  "What a compliment to our friend Livingstone!" said Mr. Mitchel, with alaugh.

  "I found the Mexican suspicious and difficult to approach at first. So Iquickly decided that only a bold play would be successful. I told himthat I was a detective, and related the incident of the stealing of theopal. At this his eyes glistened, but when I told him that the gem hadbeen sold to a man of enormous wealth who would never again part withit, his eyes glared."

  "Yes, Domingo's eyes are glary at times. Go on."

  "I explained to him that by this I meant that it would now be impossiblefor Mr. Livingstone to get the opal, and then I boldly asked him whatreward I might expect if I could get it."

  "How much did he offer?"

  "At first he merely laughed at me, but then I explained that you are myfriend, and that you merely buy such things to satisfy a hobby, andthat, having no especial desire for this particular jewel, I had littledoubt that I could obtain it, provided it would be of g
reat financialadvantage to myself. In short, that you would sell to a friend what noneother could buy."

  "Not bad, Mr. Barnes. What did Domingo say to that?"

  "He asked for a day to think it over."

  "Which, of course, you granted. What, then, is his final answer?"

  "He told me to get the opal first, and then he would talk business."

  "Bravo! Domingo is becoming quite a Yankee."

  "Of course I watched the man during the interval, in order to learnwhether or not he would consult with Mr. L., or any other adviser."

  "What did this lead to?"

  "It led to Pasquale Sanchez."

  "What! More Mexicans?"

  "One more only. Sanchez lives in a house near where Domingo has hisroom. He tells me that he comes from the same district as Domingo.Although Domingo did not make a confidant of him, or even ask hisadvice, his visit to his friend cleared up some things for me, for byfollowing Domingo I came upon Sanchez."

  "What could he know, if, as you say, he was not in the confidence ofDomingo?"

  "He knew some things which seem to be common knowledge in his nativeland. He is even more Americanized than his friend, for he fullyappreciates a glass of whiskey, though I doubt not the habit was firstacquired at home. I should think it would take many years to acquiresuch a--let me call it--capacity. I never saw a man who could swallowsuch powerful doses without a change of expression. The only effectseemed to be to loosen his tongue. It is needless to repeat all thestages by which I approached my subject. He knew all about the Aztecopals,--for really there are two of them,--except of course theirpresent whereabouts. I asked him if they would be valuable, supposingthat I could get possession of them. He was interested at once. 'You getthem, and I show you million dollars.' I explained to him that I mightsee a million dollars any day by visiting the United States Treasury,upon which, with many imprecations and useless interpolations of badSpanish, he finally made it clear to me that the priests who have theidol from which the opals were obtained, have practically little powerover their tribe while the 'god is in heaven,' as has been explained tothe faithful, the priests not caring to exhibit the image without itsglowing eyes. These priests, it seems, know where the mine is from whichthese opals were taken, and they would reveal this secret in exchangefor the lost opals, because, though this mine is said to be very rich,they have been unable themselves to find any pieces sufficiently largeand brilliant from which to duplicate the lost gems."

  "Then you think it was to obtain possession of this opal mine that Mr.Livingstone sought to obtain Mrs. Gray's opal?"

  "Undoubtedly. So certain am I of this that I would wager that he willendeavor to get the opal from you."

  "Let me read a letter to you, Mr. Barnes."

  Mr. Mitchel took out a letter and read as follows:

  "'LEROY MITCHEL, Esq.:--

  "'Dear Sir--In my letter of recent date I offered to you the duplicate of the Aztec Opal which you recently purchased from Mr. Gray. You paid Gray twenty thousand dollars, and I expressed my willingness to sell you mine for five thousand dollars in advance of this sum. In your letter just received, you agree to pay this amount, naming two conditions. First, you ask why I consider my opal worth more than the other, if it is an exact duplicate. Secondly, you wish me to explain what I meant by saying on the yacht that "women are poor conspirators."

  "'In reply to your first question, my answer is, that however wealthy I may be I usually do business strictly on business principles. These opals separately are worth in the open market twenty thousand dollars each, which sum you paid to Gray. But considering the history of the gems, and the fact that they are absolute duplicates the one of the other, it is not too much to declare that as soon as one person owns both gems, the value is enhanced twofold. That is to say, that the pair of opals together would be worth seventy or eighty thousand dollars. This being true, I consider it fair to argue that whilst I should not expect more than twenty thousand dollars from any other person in the world, twenty-five thousand is a low sum for me to ask of the man who has the duplicate of this magnificent harlequin opal.

  "'In regard to my remark about the "conspirators," the conspiracy in which I had induced Mrs. Gray to take part was entirely honorable, I assure you. I knew of Gray's financial embarrassments and wished to aid him, without, however, permitting him to suspect my hand in the affair. He is so sensitive, you know. I therefore suggested to Mrs. Gray that she entrust her jewel to me, and promised to dispose of the two jewels together, thus realizing the enhanced value. I pointed out that in this manner she would be able to give her husband much more than he could possibly secure by the sale of the one stone.

  "'Trusting that I have fully complied with your conditions, I will call upon you at noon to-day, and will bring the opal with me. We can then complete the transaction, unless you change your mind in the interval. Cordially yours, etc.'

  "So you see," said Mr. Mitchel, "he offers to sell me his opal, ratherthan to purchase mine."

  "It is strange," said Mr. Barnes, musingly. "Why should he relinquishhis hope of getting possession of that mine? I do not believe it. Thereis some devilish trickery at work. But let me tell you the rest of mystory."

  "Oh, is there more?"

  "Why, certainly. I have not yet explained my reason for thinking youmight be in danger."

  "Ah, to be sure. My danger. I had forgotten all about it. Pardon mystupidity."

  "In further conversation with this Sanchez I put this proposition tohim. 'Suppose,' said I, 'that your friend Domingo had one of theseopals, and knew the man who had the other. What would he do?' His answerwas short, but to the point. 'He get it, even if he kill.'"

  "So you think that Domingo might try murder?"

  "It is not impossible."

  "But, Mr. Barnes, he does not want my life. He wants the opal, and asthat is, or rather has been until to-day, in the safety-vaults, howcould he get it, even by killing me?"

  "You have just admitted that it is not in the vaults at present."

  "But it is quite as much out of his reach in my safe here in thisroom."

  "But you might take it out of the safe. You might, in some manner, bepersuaded to do so, to show it to some one."

  "Very true. In fact, that is why it is here. I must compare my opal withthe one which Mr. Livingstone offers for sale, before I part withtwenty-five thousand dollars. For you must remember that such a sum is afabulous price for an opal, even though, as you know, these are thelargest in the world."

  "From a money standpoint, of course, your precaution is proper. But doyou not see that you are really making possible the very danger of whichI came to warn you?"

  "You mean----"

  "Murder in order to get possession of that accursed ill-luck stone. ButI fear my warning is not appreciated."

  "Indeed, my friend, it is, and I am glad that you have come in person toacquaint me with your anxiety in my behalf. This I will more thoroughlyexplain to you later. For the present, I may say that I am glad to haveyou here as a possible witness, in case murder, or any other crime,should be attempted."

  "What other crime do you anticipate as possible? Surely not theft?"

  "Why not?"

  "What! Steal that opal from you, while you are present to see the deedcommitted? That is a joke." Mr. Barnes laughed heartily.

  "Your laugh is a compliment," said Mr. Mitchel. "Yet that is exactlywhat I most anticipate--theft. I am not sure that it may not beundertaken before my very eyes. Especially as the thief did not hesitateat a table filled with men and women. Sh! He is here."

  The electric street-door bell had sounded. Mr. Mitchel arose, and spokehurriedly in a low tone.

  "That is probably Mr. Livingstone come to sell his opal, or to stealmine. We shall see. Especially I desire that you should see.Consequently I have arranged matters in advance. Slip behind thisbookcase, which I have placed a
cross the corner that you may have roomto breathe. The books on the top shelf have been removed, and the tintedglass of the doors will not obstruct your view. From behind you will beable to see through quite readily."

  "Why, you seem to have expected me," said Mr. Barnes, getting into thehiding-place.

  "Yes, I expected you," said Mr. Mitchel, vouchsafing no furtherexplanation. "Remember now, Mr. Barnes, you are not to interfere,whatever happens, unless I call you. All I ask is that you use youreyes, and that good eyes will be required be sure, or I never shouldhave arranged to have an extra pair to aid me on this occasion."

  A moment later Williams announced Mr. Livingstone.

  "Ask Mr. Livingstone to come up here to the library," said Mr. Mitchel,and a little later he greeted his guest.

  "Ah, glad to see you, Mr. Livingstone. Take a seat here by my desk, andwe can get right to business. First, though, let me offer you a cigar."

  Mr. Livingstone chose one from the box which Mr. Mitchel offered to him,and lighted it as he sat down.

  "What a companionable feeling steals over one as he puffs a fine cigar,Mr. Mitchel! Who would accept such an offering as this and betray theconfidence of his host?"

  "Who, indeed?" said Mr. Mitchel. "But why do you say that?"

  "Why, I am not entirely a fool. You do not trust me. You are not sure inyour own mind whether or not I committed a theft on board of the yacht."

  "Am I not?" Mr. Mitchel asked this in a tone that made Mr. Livingstonelook upon it in the light of a question, whereas Mr. Barnes, behind thebookcase, considered it as an answer.

  "Why, no," said Mr. Livingstone, replying. "Had you believed that theopal changed hands honorably, even though secretly, under cover of thedarkness, you would not have asked me to explain my allusion to'conspirators.' I trust, however, that my letter made it all clear toyou."

  "Quite clear."

  "Then you are still willing to make the purchase?"

  "If you still desire to sell. A certified check for the amount is readyfor you. Have you brought the opal?"

  "Yes. Have you the duplicate? It would be well to compare them beforeyou purchase."

  "If you do not mind, I will do so."

  Mr. Mitchel turned to his safe and brought out a box which Mr. Barnesthought he recognized. Opening it he drew out a marvellous string ofpearls, which he laid aside, while he took from beneath, a velvet casewhich contained the opal. Returning the pearls to the box he restoredthat to the safe, which he locked.

  "Now, if you will let me see your opal," said Mr. Mitchel, "I willcompare the gems."

  "Here it is," said Mr. Livingstone, handing Mr. Mitchel his opal.

  Mr. Mitchel took the two opals in his hand, and, as they lay side byside, he examined them closely, observing the play of light as he turnedthem in various positions. To his critical eye they were marvellouslybeautiful; matchless, though matched. None could see these two andwonder that the old priests in Mexico had searched in vain for a secondpair like them.

  "Do you know why these opals are so exactly alike?" asked Mr.Livingstone.

  "I am not sure," said Mr. Mitchel, apparently absorbed in his scrutinyof the opals. "I have heard many reasons suggested. If you know the trueexplanation, suppose you tell me."

  "Willingly. You will observe that in each opal red lights seem topredominate on one side, while the blue and green are reflected from theother. Originally, this was one great egg-shaped opal, and it was cutin that shape, and then poised in the forehead of a single-eyed idol bythe priests of a thousand years ago. By an ingenious mechanism the eyecould be made to revolve in its socket, so that either the red or theblue-green side would be visible, as it suited the purpose of thepriests, when overawing the tribesmen by pretended prophecies and othermiraculous performances. In more recent times, since the advent of theChristians, one-eyed idols are not so plausible, and the priests cut theopal in half, thus making it serve in what may be termed a modernizedidol."

  "Yes, I have heard that tale before. In fact, I have a metal ring whichI was told would exactly encircle the two opals, if placed together toform an egg."

  "How could you have such a thing?" asked Mr. Livingstone, with genuinesurprise.

  "The man who stole the jewels, so the story goes, wishing to enhancetheir value as much as possible, arranged this as a scheme by which thegenuineness of the opals could be tested. He placed the opals together,as before they were cut, and had a silver band made which would exactlyclasp them in that position. This band opens and shuts with a springcatch, like a bracelet, and as, when closed, it exactly fits the opals,holding the two firmly together, the owner of the band could easily tellwhether the true opals were before him, or not. In some way the opalswere next stolen without the band, and their whereabouts was unknownwhen a dealer in Naples told me the story of the silver band, which heoffered to sell me. I scarcely credited his tale, but as all largejewels might in time be offered to me, I thought it well to purchase theband."

  "Why, then, if you still have it, it would be interesting to make thetest, would it not?"

  "Yes, I think so. I will get the band."

  Mr. Mitchel placed the two opals on the desk before him and went over tothe safe, where he was occupied some time opening the combination lock.While he was thus busy a strange thing seemed to occur. At least itseemed strange to Mr. Barnes. He had marvelled to see Mr. Mitchel placethe two opals within easy reach of Mr. Livingstone, and thendeliberately turn his back while he opened the safe. But what seemedmore mysterious was Mr. Livingstone's action. Mr. Mitchel had scarcelystooped before the safe when his guest leaned forward, with both armsoutstretched simultaneously; his two hands grasped the opals, the handsthen swiftly sought his vest pockets, after which he calmly puffed hiscigar. Thus he seemed to have taken the opals from the table and to haveplaced them in his pockets. Yet how could he hope to explain theirabsence to Mr. Mitchel? This thought flashed through Mr. Barnes's mindas his eyes instinctively turned again to the desk, when, to his utterastonishment, he saw the opals exactly where Mr. Mitchel had placedthem. Had the thought that he could not explain away the disappearancecaused the man to change his mind at the very moment when he hadimpulsively clutched the treasures? Mr. Barnes was puzzled, and somewhatworried too, for he began to fear that more had happened, or washappening, than he comprehended.

  "Here is the band," said Mr. Mitchel, returning to the desk, andresuming his seat. "Let us see how it fits the opals. First, let me askyou, are you confident that you are selling me one of the genuine Aztecopals?"

  "I am. I have a history which makes its authenticity indubitable."

  "Then we will try our little test. There; the band clamps the twoperfectly. Look for yourself."

  "Certainly; the test is complete. These are undoubtedly the Aztec opals.Mr. Mitchel, you are to be congratulated upon gaining possession of suchunique gems."

  Mr. Livingstone arose as though about to leave.

  "One moment, Mr. Livingstone; the jewels are not mine, yet. I have notpaid you for yours."

  "Oh, between gentlemen there is no hurry about such matters."

  "Between gentlemen it may be as you say. But you said this was to bestrictly in accordance with business methods. I prefer to pay at once.Here is my certified check. I will also ask you to sign this receipt."

  Mr. Livingstone seemed to hesitate for a moment. Mr. Barnes wonderedwhy? He sat at the desk, however, and, after reading the receipt, hesigned it, and took the check, which he placed in his pocketbook,saying:

  "Of course we will be businesslike, if you insist, though I did notanticipate that you would take me so literally. That being over, Mr.Mitchel, I will bid you good morning."

  "You may go, Mr. Livingstone, when the transaction is over, but notbefore."

  "What do you mean?" demanded Mr. Livingstone aggressively, as he turnedand faced Mr. Mitchel, who now stood close beside him.

  "I mean that you have accepted my money. Now I wish you to give me theopal."

  "I do not understand. Ther
e are your opals, just where you placed themon the table."

  "We will have no quibbling, Mr. Livingstone. You have taken twenty-fivethousand dollars of my money, and you have given me in exchange aworthless imitation. Not satisfied with that, you have stolen my genuineopal."

  "Damn you----"

  Mr. Livingstone made a movement as though to strike, but Mr. Mitchelstepped quickly back, and, quietly bringing forward his right arm, whichhad been held behind his back, it became evident that he held in hishand a revolver of large calibre. He did not raise the weapon, however,but merely remarked:

  "I am armed. Think before you act."

  "Your infernal accusation astounds me," growled Mr. Livingstone. "Ihardly know what to say to you."

  "There is nothing to say, sir. You have no alternative but to give me myproperty. Yes, you have an alternative,--you may go to prison."

  "To prison!" The man laughed, but it was not a hearty laugh.

  "Yes, to prison. I believe that is the proper lodging-place for athief."

  "Take care!" cried Mr. Livingstone, advancing upon Mr. Mitchel.

  "Mr. Barnes," said Mr. Mitchel, still without raising his weapon. Atthis the man stopped as quickly as he had when the weapon was firstshown. He seemed confounded when the detective stepped into view.

  "Ah," he sneered; "so you have spies upon your guests?"

  "Always, when my guests are thieves."

  Again the words enraged him, and, starting forward, Mr. Livingstoneexclaimed:

  "If you repeat those words, I'll strangle you in spite of your weaponand your spy."

  "I have no wish to use harsh language, Mr. Livingstone. All I want is myproperty. Give me the two opals."

  "Again I tell you they are on your desk."

  "Where are the genuine opals, Mr. Barnes? Of course you saw him committhe--that is, you saw the act."

  "They are in his vest pocket, one in each," said the detective.

  "Since you will not give them to me, I must take them," said Mr.Mitchel, advancing towards Mr. Livingstone. That gentleman stoodtransfixed, livid with rage. As his antagonist was about to touch hisvest pocket, his hand arose swiftly and he aimed a deadly blow at Mr.Mitchel, but not only did Mr. Mitchel as swiftly lower his head, thusavoiding the blow, but before another could be struck, Mr. Barnes hadjumped forward and grasped Mr. Livingstone from behind, pinioning hisarms and holding him fast by placing his own knee in his adversary'sback. Mr. Livingstone struggled fiercely, but almost instantly Mr.Mitchel took the opals from his pockets, and then quietly remarked:

  "Release him, Mr. Barnes. I have my property."

  Mr. Barnes obeyed, and for an instant Mr. Livingstone seemed weighinghis chances, but evidently deciding that the odds were in all waysagainst him, he rushed from the apartment and out of the house.

  "Well, Mr. Mitchel," said Mr. Barnes, "now that the danger has passed,an explanation seems to be in order. You seem to have four opals."

  "Yes; but that is merely seeming. You will readily understand why Iwished your eyes, for without them I could not have taken my own off ofthe opals even for an instant."

  "Then you purposely turned your back when you went to get the silverband?"

  "Assuredly. Why could I not have taken out the band in the firstinstance, and why did I lock the safe, making it necessary for me totake time with the combination? Simply to give my man the opportunityto do his trick. You see, I knew before he came here exactly what hewould do."

  "How did you know?"

  "You will recall that in his letter he offers to sell me the duplicateopal. That made me smile when I read it, for I already had been notifiedthat he had had duplicates of his opal made."

  "You had been notified?"

  "Yes. This whole affair flatters my vanity, for I anticipated the eventin its minutest detail, and all by analytical deduction. You quitecorrectly argued that Livingstone would not abandon his quest of theopal. I also reached that point, and then I asked myself, 'How will heget it, knowing that I would not sell?' I could find but one way. Hewould offer to sell his, and during the transaction try to steal mine.As he would need both opals in his Mexican mining venture, his onlychance of carrying both away with him would be to have two others toleave in their stead. Thus I argued that he would endeavor to have twoduplicates of his opal made. Ordinarily, opals are not sufficientlyexpensive to make it pay to produce spurious specimens. Consequently, ithas been little done; indeed, I doubt that the members of the trade inthis city have any idea that doublet opals have been made and sold inthis city. But I know it, and I know the man who made the doublets.These were common opals, faced with thin layers of a fine quality of'harlequin' which often comes in such thin layers that it ispractically useless for cutting into stones, though it has been utilizedfor cameos and intaglios. This lapidary does his work admirably, and hiscement is practically invisible. I went to this man and warned him thathe might be called upon to duplicate a large and valuable opal, and Iarranged that he should fill the order, but that he should notify me ofthe fact."

  "Ah, now I understand. The genuine opals lay on the desk, and when youturned to the safe Livingstone merely exchanged them for the spuriousdoublets. But tell me why did he risk bringing the real opal here atall? Why not offer you one of the doublets, and then merely have oneexchange to make?"

  "He was too shrewd to risk that. In the first place, he knows I am anexpert, and that I would compare the two jewels before making thepurchase; he feared that under such close scrutiny I would discover thedeception. Secondly, the two genuine opals absolutely match each other.So also the two doublets are actual mates. But the doublets onlyapproximately resemble the real opals."

  "Mr. Mitchel, you have managed Livingstone admirably, but there stillremains the man Domingo. Until he is disposed of I still think there isdanger. Pardon my pertinacity."

  "I told you at the beginning of this incident that I had a spy uponLivingstone, but that though the method was commonplace, my choice of aspy was unique. My spy was Livingstone's partner, Domingo."

  "What! You were on intimate terms with Domingo?"

  "Was not that my best course? I found the man, and at once explained tohim that as Livingstone never could get my opal, it would be best toshift the partnership and aid me to get Livingstone's. Thus you see,having, as it were, conceived the logical course for Livingstone topursue, I had his partner Domingo suggest it to him."

  "Even the idea of the doublets?"

  "Certainly. I gave Domingo the address of the lapidary, and Domingosupplied it to Livingstone."

  "Mr. Mitchel, you are a wonder as a schemer. But now you have Domingo onyour hands?"

  "Only for a short time. Domingo is not such a bloodthirsty cutthroat asyour friend Sanchez made you believe. He readily admitted that the gamewas up when I explained to him that I had one of the opals, a fact whichLivingstone had not communicated to him. I had little difficulty inpersuading him to become my assistant; money liberally applied oftenproving a salve for blasted hopes. Besides, I have raised his hopesagain, and in a way by which he may yet become possessed of that opalmine, and without a partner."

  "Why, how do you mean?"

  "I shall give him the doublets, and I have no doubt he can palm them offon the old priests, who will not examine too closely, so anxious arethey to see the eyes of the idol restored."

  "There is yet one thing that I do not fully understand. Sanchez toldme----"

  "Sanchez told you nothing, except what he was instructed to tell you."

  "Do you mean to say----"

  "I mean that Sanchez's story of my danger was told to you so that youwould come here this morning. You noted yourself that I must haveexpected you, when you found the bookcase arranged for you. I had anidea that I might need a strong and faithful arm, and I had both. Mr.Barnes, without your assistance, I must have failed."