There was a long silence. Finally Grassi looked up.

    "It's an outrage!" he exclaimed. "I don't comprehend it in the least. . . . And the blood! Do you think, sir, that this vase had anything to do with the death of Mr. Coe?"

    "Without doubt." Vance was watching the Italian with a puzzled look. "But pray sit down again, Mr. Grassi. There are one or two more questions I should like to ask you."

    The other resumed his seat reluctantly.

    "If you were with Miss Lake at the Country Club late last night," Vance proceeded, "how did it happen that you and she returned to the house at different hours? I presume, of course, that you accompanied her back to the city."

    Grassi appeared embarrassed.

    "It was Miss Lake's suggestion," he said, "that we should not be heard entering the house at the same time. So I waited in Central Park for a quarter of an hour after she had gone in."

    Vance nodded.

    "I thought as much. It was the proximity of your two returns that made me conclude that possibly you had been together last night. And furthermore, business appointments with curators of the Metropolitan Museum are not apt to extend into the early hours of the morning. . . . But what reason did Miss Lake give for the deception?"

    "No particular reason. Miss Lake merely said she thought it would be better if Mr. Brisbane Coe did not hear us coming in together."

    "She specifically mentioned Mr. Brisbane Coe?"

    "Yes."

    "And she did not mention Mr. Archer Coe?"

    "Not that I remember."

    "That is quite understandable," Vance remarked. "Uncle Brisbane was her ally in her engagement to Mr. Wrede; and she may have feared that he would not have approved of her being out so late with another man. . . . The older generation, Mr. Grassi, is inclined to be strait-laced about these little matters. The modern girl is quite different."

    The Italian was manifestly grateful for Vance's attitude, and bowed his appreciation.

    Vance strolled to the window.

    "By the by, Mr. Grassi, your quarters here are the suite of rooms at the front of the house on this floor, are they not?"

    "Why, yes," the man replied, lifting his eyebrows. "They are directly over the drawing-room and den."

    "When you came in last night—or rather, this morning—where did you hang your hat and coat?"

    Again a cautious look came into the Italian's eyes.

    "I did not wear an outer coat. But I carried my hat and stick to my own room."

    "Why? There is a coat closet in the lower hall."

    Grassi moved uneasily, and I could have sworn the pallor of his face increased.

    "I did not care to make a noise opening and shutting the closet door," he explained.

    Vance made no comment, and there was a short silence. Presently he turned from the window and walked back to the desk.

    "That will be all for the present," he said pleasantly. "And thank you for your help. . . . Would you mind waiting in your room? We shall probably want to question you again before the afternoon is over. I shall see that Gamble serves you luncheon."

    The man rose and started to say something. But, evidently thinking better of it, he merely bowed and went down the passageway of the hall toward the front of the house.

    Markham was immediately on his feet.

    "What about that broken vase?" he demanded, pointing at the parcel of porcelain fragments on the desk. "Was that the thing with which Archer Coe was struck over the head?"

    "Oh, no." Vance picked up one of the larger pieces and snapped it easily between his fingers. "This delicate Ting yao china would crack under the least pressure. If a man were struck with such a vase he would hardly feel it. The vase would simply break into pieces."

    "But the blood. . . ."

    "There was no blood on Archer's head." Vance selected one of the fragments and held it up. "Moreover, please note that the blood is not on the outer glaze, but on the inside of the vase. The same is true of the little piece I found on the table downstairs."

    Markham looked at Vance in amazement.

    "How, in the name of Heaven, do you account for that?"

    Vance shrugged.

    "I'm not accounting for it at present—not altogether. And yet, it's a most fascinatin' point. The only noticeable blood in this affair is that which trickled from Brisbane's wound and from the Scottie's head. But I can't possibly connect this broken vase with Brisbane's death or with the Scottie."

    "And how do you connect it with Archer's death?"

    Vance became evasive.

    "Wasn't it standing on the table directly behind the seat that Archer was occupying when Gamble left the house last night to indulge his taste for the art of the cinema?"

    "What of it?" queried Markham, with no attempt to curb his exasperation.

    Vance took out his cigarette-case and sighed.

    "What of it, indeed? . . . Give me a little more time," he said. "I have a fairly definite idea about this broken vase with the bloodstains on the inside; but it's too fantastic—too incredible. I want to verify my suspicions. . . ." His voice trailed off, and he lighted his cigarette meditatively.

    Markham regarded him a while and then said:

    "The whole affair strikes me as fantastic and incredible."

    Vance exhaled a blue ribbon of smoke.

    "Suppose we talk to Wrede," he suggested. "We may know more when he has unburdened his heart to us. He has ideas—otherwise he would not have had Gamble phone direct to you."

    Markham gave an order to Heath, but at that moment Burke announced the arrival of the wagon from the Department of Public Welfare. The Sergeant went into the hall and was half-way down the stairs when Vance turned quickly from his contemplation of a Ch'ien Lung gourd-shaped vase in mille-fleur pattern, and hastened after him.

    "Just a moment, Sergeant!"

    So impetuous was Vance's manner that Markham and I followed him into the hall.

    "I could bear," Vance called down to Heath, "to snoop in the pockets of Brisbane's suit before it's taken away. . . . Would you mind?"

    "Certainly not, Mr. Vance." Heath, for some reason, was in good humor. "Come along."

    We all went to the library. The Sergeant closed the door.

    "I had the same idea," he said. "I've been figuring right along that maybe that slick butler was lying to us about the ticket to Chicago."

    It took but a short time to empty the pockets of Brisbane Coe's suit to the library table. But there was nothing of interest among the contents, only the usual items to be found in a man's pockets—a wallet, handkerchiefs, keys, a fountain-pen, a watch, and the like. There were, however, the ticket and berth reservations to Chicago, and also the parcel-room check for the suit-case.

    Heath was crestfallen, and expressed himself in violent terms.

    "The ticket's here all right," he added; "so I guess he intended to go, after all."

    Vance, too, was disappointed.

    "Oh, yes, Sergeant, he intended to go. But it was not the ticket that was worrying me. I was hoping to find something else."

    "What?" asked Markham.

    Vance gave him a vague look.

    "Really, don't y' know, I haven't the slightest idea." He would say no more.

    Heath summoned the two men waiting in the hall with their basket, and the body of Brisbane Coe was taken away to join that of his brother at the mortuary.

    As the men went out to the car, Snitkin came in with the dead man's suit-case.

    "I had a hell of a time getting it," he complained apologetically. "Those crabs at the station wouldn't turn it over, and I had to go to Headquarters and get an order from the Inspector."

    "There wasn't any hurry." The Sergeant tried to smooth the detective's ruffled feelings.

    Then, at Vance's suggestion, he opened the suitcase and examined the contents. They consisted merely of the items which would ordinarily be taken by a man making a short trip.

    "Here, you." Heath jerked his head at Gamble. "Look in here and see if these are the things you packed."

    Gamble obeyed fearfully. After a moment's inspection he nodded with obvious relief.

    "Yes, sir. There's nothing there except what I put in."

    Vance nodded to Heath, and the Sergeant ordered Gamble to put the bag away.

    "And you, Snitkin," he added, "wait upstairs."

    Both men disappeared, and the Sergeant went to the drawing-room doors and pulled them apart.

    "Mr. Wrede," he called. "You're wanted."

    Wrede came into the library with a haggard, questioning look in his eyes.

    "Have you learned anything, Mr. Markham?" His voice seemed to quaver slightly, and as he spoke, his eyes roved over the room. "Where's Mr. Grassi?"

    "Mr. Grassi's upstairs." Markham motioned to a chair. "And I'm sorry to say that thus far we have learned very little. . . . We are hoping that you may be able to help us out of our quandary."

    "Good Lord! I wish I could." Wrede was like a man on the verge of collapse. "It's horrible!"

    Vance had been watching him from under half-closed eyelids.

    "It's more horrible than you perhaps realize," he said. "Brisbane Coe has also been murdered."

    Wrede looked around him in a dazed way and sank heavily into the nearest chair.

    "Brisbane?" His voice seemed to come from afar. "But why—why. . . ?"

    "Why, indeed?" Vance spoke harshly: there was none of the detached suavity in his manner that had been so noticeable during his interrogation of Grassi. "Nevertheless, he's dead. He, too, was stabbed in the back with a curiously shaped instrument."

    Wrede stared straight ahead. His lips moved, but no sound came from them.

    "Tell us what you know about this double murder, Mr. Wrede," Vance went on with grim relentlessness.

    A shiver ran over Wrede's body.

    "I know nothing about it," he replied after a painful pause. "Gamble told me this morning that Brisbane was in Chicago."

    "He started for the station yesterday afternoon, but returned here last night—to meet his death."

    "Why—should he return?" stammered Wrede.

    "Have you any ideas on the subject?"

    "I?" The man's eyes opened wide. "Not the slightest idea."

    "What do you know of the conditions here at the Coe house yesterday? I would like as full a description as you can give; and I would also like a detailed account of your own movements yesterday."

    "Why my movements?" Wrede's tone was weak and frightened.

    "If you don't care to explain them . . ." began Vance pointedly, and stopped.

    "I have no reason for secrecy," the other answered quickly. "I was here talking to Archer Coe from ten to twelve yesterday morning—"

    "About ceramics—or Miss Lake?"

    Wrede caught his breath.

    "Both," he answered weakly. "The fact is, Archer and I had a somewhat bitter session regarding my coming marriage with Miss Lake. But it was nothing unusual. He was, as you may know, violently opposed to the marriage. Brisbane took part in the discussion, and called Archer some rather harsh names. . . ."

    "And after twelve?"

    "I lunched in my apartment. Then I went to an auction at the American Art Galleries. But there was nothing there that interested me particularly; and, besides, I had a bad headache. So I came home around three, and lay down. I did not leave my apartment again until this morning, when Gamble phoned me."

    "You live next door, do you not?"

    "The first house to the east, across the double vacant lot. It's an old residence that has been converted into an apartment house. I occupy the second floor."

    "Who owns the vacant lot?"

    "It is part of the Coe estate. Archer put it to lawn, and erected the iron fence on the street. He said he wanted the light and space, and refused to sell."

    Vance nodded indifferently.

    "So I understood. . . . And you remained in your apartment from three o'clock yesterday afternoon until this morning?"

    "That's right. I had a beastly headache. . . ."

    "Did you see Miss Lake yesterday?"

    "Yes, in the morning, when I was here. The fact is, I made an appointment with her for last night—at the Country Club. But when I got home yesterday afternoon, I called her by phone and excused myself. I was in no condition for dancing."

    "Mr. Grassi substituted for you," said Vance.

    Wrede's eyes clouded, and he set his jaws.

    "So she told me this morning." (I could not determine whether the man was telling the truth or merely being gallant.)

    "When Gamble phoned you this morning," Vance asked, "what was your mental reaction to the news?"

    Wrede frowned, and it was a considerable time before he answered.

    "That would be difficult to analyze. . . . I was not overfond of Archer," he admitted; "and I was not personally distressed by the report of his death. But I was extremely puzzled. It was not like Archer to take his own life; and—frankly—I had very grave doubts. That is why I hastened over here,—I wanted to see for myself. Even when I had looked through the keyhole I could scarcely believe the evidence of my vision, knowing Archer as well as I did. For that reason I advised Gamble to get in immediate touch with Mr. Markham."

    Vance's stony contemplation of Wrede did not relax.

    "You acted wisely," he observed, with a tinge of sarcasm. "But if you did not believe that Archer Coe had committed suicide, there must have been in your mind another possibility—to wit: that of murder.—Who, Mr. Wrede, do you think would have had sufficient motive to commit the crime?"

    Wrede did not answer at once. He appeared sorely troubled and ran his fingers several times through his hair.

    "That is a question I have been trying to answer all morning," he replied without looking at Vance. "One may speculate, of course, but it would not be fair to voice those speculations without definite evidence of some kind. . . ."

    "Mr. Grassi?"

    Again a black cloud passed over Wrede's face.

    "I—I—really, Mr. Vance, I'm not well acquainted with the man. He was after Coe's collection of Chinese ceramics; but that would hardly constitute a motive for murder."

    "No-o." Vance smiled frigidly. "What about Miss Lake?"

    Wrede almost leaped from his seat.

    "That suggestion is outrageous!" he cried, glowering at Vance. "How dare you—?"

    "Spare me the drama," Vance cut in, with a contemptuous smile. "I'm deuced difficult to impress. . . . We're merely discussing possibilities, and we can do far better without a display of histrionic talent, however noteworthy."

    Wrede sat back, with a mumbled remark which we could not make out.

    "What do you think of Liang, the cook?" Vance asked next.

    The man glanced up with a swift, shrewd look.

    "Liang, eh? That's quite different. There's something secretive and underhand about that Chinaman. I've never wholly understood his being here. He's certainly not a cook by profession; and from my apartment window I've often seen him sitting on the rear porch writing for hours. My impression is he's a spy of some kind. And he knows Chinese art. Several times I've caught him in this very room inspecting the vases, and studying the signatures on their bases, and running the tips of his yellow fingers over their glazes with the air of a connoisseur. . . . And I've never liked his manner round this house,—he's sly and over-polite. I distrusted him from the first." Wrede nodded his head sagely. "If you knew more of what was back of his presence here, you might know more of Archer Coe's death. . . . At least," he hastened to add, "that is my impression."

    Vance stifled a mild yawn.

    "The oriental temperament is full of mystic potentialities," he commented. "And my own impression is that Liang knows something about what happened here last night. But, as you suggest, a motive in that direction is still lacking." He leaned against the mantel and let his gaze drift into space. "On the other hand, you yourself had abundant motive for doing away with Archer Coe."

    Wrede, to my surprise, did not appear to be offended by this remark.

    "Archer was admittedly opposed to your marriage with his niece," Vance went on. "He might even have brought sufficient influence to bear to stop it altogether. And until he died Miss Lake was limited to a small allowance. She would have received her patrimony at Archer's decease. Thus, if you had successfully put Archer out of the way, you would have at once gained a fairly wealthy bride—with no obstacles. Is it not so, Mr. Wrede?"

    The man gave a harsh laugh.

    "Yes, I suppose so. As you point out, I had ample motive for murdering Archer. But, on the other hand, I would have had no reason whatever for murdering Brisbane."

    "Ah, yes—Brisbane. Quite—quite. That second corpse complicates the whole matter."

    "Where was Brisbane's body found, may I ask?"

    "In the coat closet at the end of the lower hall. . . . You didn't, perchance, open the coat closet this morning?"

    "No!" Wrede shuddered. "But I came very near it. Instead, I threw my hat on a chair in the drawing-room."

    Vance shook his head in satirical sadness.

    "My word! How consistently every one seems to have avoided that closet since Brisbane's occupation of it!"

    "Perhaps," suggested Wrede significantly, "Liang was not ignorant of its contents."

    "Who knows?" sighed Vance. "And Liang certainly would not tell us. Sad . . . sad. . . ."

    Wrede lapsed into introspection. Presently he spoke.

    "What I can't understand is that bolted door upstairs."

    "Neither can we," said Vance, in a matter-of-fact tone. "It's most confusin'. But don't let that point disturb your slumbers tonight, Mr. Wrede. I'm thoroughly convinced you didn't bolt it."

    The man jerked his head up in a queer way.

    "Oh, thanks." His attempt at pleasantry was unsuccessful. "Have you found the weapon?" he asked lamely. "That might give you a clue."

    "I'm sure it would," agreed Vance.

    Heath, who had been standing by the front windows, stepped forward.

    "That reminds me." He gave Vance a disgruntled look: obviously he did not like the other's method of interviewing Wrede. "The boys and I are going to give this house a swell looking-over. . . . All right with you, Mr. Markham?"

    Markham nodded.

    "Go to it, Sergeant. The sooner the better."

    Heath went from the room, and Vance resumed his interrogation.

    "By the by, Mr. Wrede, are you interested in Chinese ceramics?"

    "Not particularly." The man was obviously puzzled by the question. "I have a few pieces, but I'm no expert. However, I couldn't help learning something about the subject during my long association with Archer."

    Vance walked to the circular teak-wood table behind the davenport, and pointed at the Tao Kuang vase.

    "What's your opinion of this Ting yao?"

    Wrede rose and came forward.

    "Ting yao?" There was a perplexed look in his eyes. "That's not a Ting yao, is it?"

    "I don't believe it is." Vance pretended to study it. "But I was under the impression Archer Coe kept a Ting yao vase of the same shape on this table."

    Wrede stood, his hands behind him, looking down at the vase. Suddenly he said:

    "By Gad, he did, Mr. Vance! But this isn't the vase."

    "When did you last see the original vase?"

    "I couldn't say. I was in this room yesterday morning—but I didn't notice. There were other things on my mind." He looked at Vance questioningly. "Has this vase anything to do with—with—?"

    "It's difficult to say," Vance replied. "It merely struck me as peculiar that Archer would have a vase like this in his collection."

    "It is peculiar." Wrede turned his attention again to the table. "This vase might have been substituted for the other."

    "It was," said Vance laconically.

    "Aha!" Wrede, for some reason I could not understand, seemed pleased; and I asked myself if he were thinking of Grassi.

    Vance apparently had not noticed his exclamation. He glanced at his watch.

    "That will be all, Mr. Wrede. You'd better run along and get some lunch. But we may want you tomorrow. Will you be at your apartment?"

    "Yes, all day." He hesitated. "May I see Miss Lake before I go?"

    "By all means. And you might break the news to her of Brisbane's death."

    Wrede went out, and we could hear him mounting the stairs.

    Markham rose nervously.

    "What do you make of the fellow?" he asked.

    Vance smoked a moment thoughtfully.

    "Peculiar character—far from appealin'. I wouldn't choose him for a boon companion."

    "You certainly didn't handle him with gloves."

    "He's too clever a talker to be allowed any advantage. My only hope of learning what he might possibly know was to upset his equanimity."

    "It occurred to me," said Markham, "that he might have opened the hall closet this morning, and, because of what he saw, told Gamble to phone me."

    "It's possible," Vance nodded. "The same thought flitted through my mind. But if that were so, why shouldn't he have told us the moment we arrived?"

    "Anyway, it's safe to conclude he doesn't care a great deal for Grassi. It struck me he was jealous of the Italian."

    "Oh, quite. And it was news to him that Grassi and Miss Lake were together last night. Curious situation, that." Vance frowned musingly. "But Wrede's real passion of hatred is directed toward the cook. He has sized up Liang pretty accurately. . . . It's strange that Archer, with his Sinological knowledge, didn't suspect Liang's true status."

    "Maybe he did," Markham suggested, without interest.

    Vance looked up quickly and took his cigarette from his lips.

    "My aunt! Maybe he did! . . ."

    There came a pounding of heavy footsteps on the hall stairs, and the next moment Heath was standing in the door, beaming triumphantly. He held something in his hand, and, crossing to the table, he threw the object down for our inspection.

    It was one of the most beautiful and interesting Chinese daggers I have ever seen.[11] The blade, which was square with concave sides, was of steel, delicately and minutely incised and perhaps six inches long. It tapered from a thickness of about half an inch at the guard to a stiletto-like point, and was partly encrusted with dried blood. The guard was oval-shaped, of polished gold, and engraved with the original owner's seal. The cylindrical handle was wound with vermilion silk, with the usual row of knots running down one side; and it was surmounted by a tiny figure of Kuan Ti, the Chinese God of War, carved in brown jade. That this dagger was the murder weapon was obvious at one glance.

    "Good work, Sergeant," said Vance. "Where did you find it?"

    "Under the cushion-seat of the easy chair where we found the dead guy this morning."

    "Oh, I say! Really? In Archer Coe's bedroom?" Vance seemed astonished at Heath's announcement. "Most amazin'. . . ."

    He went swiftly to the dining-room door and called Liang. When the Chinaman appeared Vance beckoned him to the table and pointed at the dagger.

    "Ever see that before, Mr. Liang?"

    The man regarded the weapon with a look devoid of all expression.

    "Yes, I have seen it many times," he responded in a flat voice. "It was always kept in that cabinet near the window, with other similar weapons of my country."

    Vance dismissed him, and walked up and down the room several times. Something disturbing was on his mind.

    Heath watched him a moment and then looked back at the dagger.

    "And not a chance to pick up a finger-print," he complained with disgust. "A silk handle." He chewed viciously on his burnt-out cigar.

    "No—no finger-prints," murmured Vance without lifting his eyes from the floor. "But that isn't the chief difficulty, Sergeant. Brisbane Coe was stabbed hours after Archer Coe was stabbed. And yet the dagger is found in Archer Coe's chair upstairs. The whole thing is mad. . . ."

    He continued pacing in a brown study. Suddenly he drew up short.

    "Sergeant! Bring me Brisbane Coe's top-coat—the black-and-white tweed one—from the hall closet." His voice held a tinge of excitement.

    Heath left the room and returned shortly with the garment.

    Vance began turning the pockets inside out. A gray silk handkerchief and a pair of gloves fell to the table. Then from the left-hand outside pocket Vance drew forth two pieces of fine, waxed linen string about four feet long. He was about to throw these to one side, when he suddenly bent forward and inspected them. One end of each piece of string was tied securely to a large bent pin.

    Heath was looking on with rapt fascination.

    "And what might that be, Mr. Vance?" he asked.

    Vance did not answer, but put his hand again into the left-hand pocket of the top-coat. When he withdrew it he was holding a long slender piece of steel.

    "Ah!" he exclaimed with satisfaction.

    We all looked down at it wonderingly. It was perhaps the last thing in the world we expected to see.

    The object which Vance had taken from the pocket of Brisbane Coe's coat was a darning-needle!