vague pattern on thetablecloth with her fingers.

  "Yet I think I must tell the police," she repeated, looking up anddropping her eyes again. Mr. Ricardo noticed that her eyelashes werevery long. For the first time Hanaud's face relaxed.

  "And I think you are quite right," he cried heartily, to Mr. Ricardo'ssurprise. "Tell them the truth before they suspect it, and they willhelp you out of the affair if they can. Not a doubt of it. Come, Iwill go with you myself to Scotland Yard."

  "Thank you," said Joan, and the pair drove away in a cab together.

  Hanaud returned to Grosvenor Square alone and lunched with Ricardo.

  "It was all right," he said. "The police were very kind. Miss JoanCarew told her story to them as she had told it to us. Fortunately,the envelope with the aluminium chain had already been delivered, andwas in their hands. They were much mystified about it, but Miss Joan'sstory gave them a reasonable explanation. I think they are inclined tobelieve her; and, if she is speaking the truth, they will keep her outof the witness-box if they can."

  "She is to stay here in London, then?" asked Ricardo.

  "Oh, yes; she is not to go. She will present her letters at the OperaHouse and secure an engagement, if she can. The criminals might belulled thereby into a belief that the girl had kept the whole strangeincident to herself, and that there was nowhere even a knowledge ofthe disguise which they had used." Hanaud spoke as carelessly as ifthe matter was not very important; and Ricardo, with an unusual flashof shrewdness, said:

  "It is clear, my friend, that you do not think those two men will everbe caught at all."

  Hanaud shrugged his shoulders.

  "There is always a chance. But listen. There is a room with ahundred guns, one of which is loaded. Outside the room there are ahundred pigeons, one of which is white. You are taken into the roomblind-fold. You choose the loaded gun and you shoot the one whitepigeon. That is the value of the chance."

  "But," exclaimed Ricardo, "those pearls were of great value, and Ihave heard at a trial expert evidence given by pearl merchants. Allagree that the pearls of great value are known; so, when they comeupon the market----"

  "That is true," Hanaud interrupted imperturbably. "But how are theyknown?"

  "By their weight," said Mr. Ricardo.

  "Exactly," replied Hanaud. "But did you not also hear at this trial ofyours that pearls can be peeled like an onion? No? It is true. Removea skin, two skins, the weight is altered, the pearl is a triflesmaller. It has lost a little of its value, yes--but you can no longeridentify it as the so-and-so pearl which belonged to this or thatsultan, was stolen by the vizier, bought by Messrs. Lustre andSteinopolis, of Hatton Garden, and subsequently sold to the wealthyMrs. Blumenstein. No, your pearl has vanished altogether. There is anew pearl which can be traded." He looked at Ricardo. "Who shall saythat those pearls are not already in one of the queer little backstreets of Amsterdam, undergoing their transformation?"

  Mr. Ricardo was not persuaded because he would not be. "I have someexperience in these matters," he said loftily to Hanaud. "I am surethat we shall lay our hands upon the criminals. We have never failed."

  Hanaud grinned from ear to ear. The only experience which Mr. Ricardohad ever had was gained on the shores of Geneva and at Aix underHanaud's tuition. But Hanaud did not argue, and there the matterrested.

  The days flew by. It was London's play-time. The green and gold ofearly summer deepened and darkened; wondrous warm nights underEngland's pale blue sky, when the streets rang with the joyous feet ofyouth, led in clear dawns and lovely glowing days. Hanaud madeacquaintance with the wooded reaches of the Thames; Joan Carew sang"Louise" at Covent Garden with notable success; and the affair of theSemiramis Hotel, in the minds of the few who remembered it, wasalready added to the long list of unfathomed mysteries.

  But towards the end of May there occurred a startling development.Joan Carew wrote to Mr. Ricardo that she would call upon him inthe afternoon, and she begged him to secure the presence of Hanaud.She came as the clock struck; she was pale and agitated; and in theroom where Calladine had first told the story of her visit she toldanother story which, to Mr. Ricardo's thinking, was yet more strangeand--yes--yet more suspicious.

  "It has been going on for some time," she began. "I thought of comingto you at once. Then I wondered whether, if I waited--oh, you'll neverbelieve me!"

  "Let us hear!" said Hanaud patiently.

  "I began to dream of that room, the two men disguised and masked, thestill figure in the bed. Night after night! I was terrified to go tosleep. I felt the hand upon my mouth. I used to catch myself fallingasleep, and walk about the room with all the lights up to keep myselfawake."

  "But you couldn't," said Hanaud with a smile. "Only the old can dothat."

  "No, I couldn't," she admitted; "and--oh, my nights were horribleuntil"--she paused and looked at her companions doubtfully--"until onenight the mask slipped."

  "What--?" cried Hanaud, and a note of sternness rang suddenly in hisvoice. "What are you saying?"

  With a desperate rush of words, and the colour staining her foreheadand cheeks, Joan Carew continued:

  "It is true. The mask slipped on the face of one of the men--ofthe man who held me. Only a little way; it just left his foreheadvisible--no more."

  "Well?" asked Hanaud, and Mr. Ricardo leaned forward, swaying betweenthe austerity of criticism and the desire to believe so thrilling arevelation.

  "I waked up," the girl continued, "in the darkness, and for a momentthe whole scene remained vividly with me--for just long enough for meto fix clearly in my mind the figure of the apache with the whiteforehead showing above the mask."

  "When was that?" asked Ricardo.

  "A fortnight ago."

  "Why didn't you come with your story then?"

  "I waited," said Joan. "What I had to tell wasn't yet helpful. Ithought that another night the mask might slip lower still. Besides,I--it is difficult to describe just what I felt. I felt it importantjust to keep that photograph in my mind, not to think about it, not totalk about it, not even to look at it too often lest I should begin toimagine the rest of the face and find something familiar in the man'scarriage and shape when there was nothing really familiar to me atall. Do you understand that?" she asked, with her eyes fixed in appealon Hanaud's face.

  "Yes," replied Hanaud. "I follow your thought."

  "I thought there was a chance now--the strangest chance--that thetruth might be reached. I did not wish to spoil it," and she turnedeagerly to Ricardo, as if, having persuaded Hanaud, she would now turnher batteries on his companion. "My whole point of view was changed. Iwas no longer afraid of falling asleep lest I should dream. I wishedto dream, but----"

  "But you could not," suggested Hanaud.

  "No, that is the truth," replied Joan Carew. "Whereas before I wasanxious to keep awake and yet must sleep from sheer fatigue, now thatI tried consciously to put myself to sleep I remained awake allthrough the night, and only towards morning, when the light was comingthrough the blinds, dropped off into a heavy, dreamless slumber."

  Hanaud nodded.

  "It is a very perverse world, Miss Carew, and things go bycontraries."

  Ricardo listened for some note of irony in Hanaud's voice, some lookof disbelief in his face. But there was neither the one nor the other.Hanaud was listening patiently.

  "Then came my rehearsals," Joan Carew continued, "and that wonderfulopera drove everything else out of my head. I had such a chance, ifonly I could make use of it! When I went to bed now, I went with thathaunting music in my ears--the call of Paris--oh, you must rememberit. But can you realise what it must mean to a girl who is going tosing it for the first time in Covent Garden?"

  Mr. Ricardo saw his opportunity. He, the connoisseur, to whom thepsychology of the green room was as an open book, could answer thatquestion.

  "It is true, my friend," he informed Hanaud with quiet authority. "Thegreat march of events leaves the artist cold. He lives aloof. Whilethe tumbrils thunder in the street
s he adds a delicate tint to thepicture he is engaged upon or recalls his triumph in his last greatpart."

  "Thank you," said Hanaud gravely. "And now Miss Carew may perhapsresume her story."

  "It was the very night of my debut," she continued. "I had supper withsome friends. A great artist. Carmen Valeri, honoured me with herpresence. I went home excited, and that night I dreamed again."

  "Yes?"

  "This time the chin, the lips, the eyes were visible. There was only ablack strip across the middle of the face. And I thought--nay, I