AT six o'clock that evening Markham called another informal conference at the Stuyvesant Club. Not only were Inspector Moran and Heath present, but Chief Inspector O'Brien dropped in on his way home from the office.[24]

    The afternoon papers had been merciless in their criticism of the police for its unsuccessful handling of the investigation. Markham, after consulting with Heath and Doremus, had explained the death of Mrs. Greene to the reporters as "the result of an overdose of strychnine—a stimulant she had been taking regularly under her physician's orders." Swacker had typed copies of the item so there would be no mistake as to its exact wording; and the announcement ended by saying: "There is no evidence to show that the drug was not self-administered as the result of error." But although the reporters composed their news stories in strict accord with Markham's report, they interpolated subtle intimations of deliberate murder, so that the reader was left with little doubt as to the true state of affairs. The unsuccessful attempt to poison Ada had been kept a strict official secret. But this suppressed item had not been needed to inflame the public's morbid imagination to an almost unprecedented degree.

    Both Markham and Heath had begun to show the strain of their futile efforts to solve the affair; and one glance at Inspector Moran, as he sank heavily into a chair beside the District Attorney, was enough to make one realize that a corroding worry had undermined his habitual equanimity. Even Vance revealed signs of tensity and uneasiness; but with him it was an eager alertness, rather than worry, that marked any deviation from normality in his attitude.

    As soon as we were assembled that evening Heath briefly epitomized the case. He went over the various lines of investigation, and enumerated the precautions that had been taken. When he had finished, and before anyone could make a comment, he turned to Chief Inspector O'Brien and said:

    "There's plenty of things, sir, we might've done in any ordinary case. We could've searched the house for the gun and the poison like the narcotic squad goes through a single room or small apartment—punching the mattresses, tearing up the carpets, and sounding the woodwork—but in the Greene house it would've taken a coupla months. And even if we'd found the stuff, what good would it have done us? The guy that's tearing things wide open in that dump isn't going to stop just because we take his dinky thirty-two away from him, or grab his poison. After Chester or Rex was shot we could've arrested all the rest of the family and put 'em through a third degree. But there's too much noise in the papers now every time we give anybody the works; and it ain't exactly healthy for us to grill a family like the Greenes. They've got too much money and pull; they'd have had a whole battalion of high-class lawyers smearing us with suits and injunctions and God knows what. And if we'd just held 'em as material witnesses, they'd have got out in forty-eight hours on habeas-corpus actions. Then, again, we might've planted a bunch of huskies in the house. But we couldn't keep a garrison there indefinitely, and the minute they'd have been called off, the dirty work would've begun. Believe me, Inspector, we've been up against it good and plenty."

    O'Brien grunted and tugged at his white cropped moustache.

    "What the Sergeant says is perfectly true," Moran remarked. "Most of the ordinary methods of action and investigation have been denied us. We're obviously dealing with an inside family affair."

    "Moreover," added Vance, "we're dealing with an extr'ordin'rily clever plot—something that has been thought out and planned down to the minutest detail, and elaborately covered up at every point. Everything has been staked-even life itself—on the outcome. Only a supreme hatred and an exalted hope could have inspired the crimes. And against such attributes, d'ye see, the ordin'ry means of prevention are utterly useless."

    "A family affair!" repeated O'Brien heavily, who apparently was still pondering over Inspector Moran's statement. "It don't look to me as though there's much of the family left. I'd say, on the evidence, that some outsider was trying to wipe the family out." He gave Heath a glowering look. "What have you done about the servants? You're not scared to monkey with them, are you? You could have arrested one of 'em a long time ago and stopped the yapping of the newspapers for a time, anyway."

    Markham came immediately to Heath's defence.

    "I'm wholly responsible for any seeming negligence on the Sergeant's part in that regard," he said with a noticeable accent of cold reproach. "As long as I have anything to say about this case no arrests are going to be made for the mere purpose of quieting unpleasant criticism." Then his manner relaxed slightly. "There isn't the remotest indication of guilt in connection with any of the servants. The maid Hemming is a harmless fanatic, and is quite incapable mentally of having planned the murders. I permitted her to leave the Greenes' to-day..."

    "We know where to find her, Inspector," Heath hastened to add by way of forestalling the other's inevitable question.

    "As to the cook," Markham went on; "she, too, is wholly outside of any serious consideration. She's temperamentally unfitted to be cast in the rôle of murderer."

    "And what about the butler?" asked O'Brien acrimoniously.

    "He's been with the family thirty years, and was even remembered liberally in Tobias Greene's will. He's a bit queer, but I think if he had had any reason for destroying the Greenes he wouldn't have awaited till old age came on him." Markham looked troubled for a moment. "I must admit, however, that there's an atmosphere of mysterious reserve about the old fellow. He always gives me the impression of knowing far more than he admits."

    "What you say, Markham, is true enough," remarked Vance. "But Sproot certainly doesn't fit this particular saturnalia of crime. He reasons too carefully; there's an immense cautiousness about the man, and his mental outlook is highly conservative. He might stab an enemy if there was no remote chance of detection. But he lacks the courage and the imaginative resiliency that have made possible this present gory debauch. He's too old—much too old... By Jove!"

    Vance leaned over and tapped the table with an incisive gesture.

    "That's the thing that's been evading me! Vitality! That's what is the bottom of this business—a tremendous, elastic, self-confident vitality: a supreme ruthlessness mingled with audacity and impudence—an intrepid and reckless egoism—an undaunted belief in one's own ability. And they're not the components of age. There's youth in all this—youth with its ambition and venturesomeness—that doesn't count the cost, that takes no thought of risk... No. Sproot could never qualify."

    Moran shifted his chair uneasily, and turned to Heath. "Whom did you send to Atlantic City to watch Sibella?"

    "Guilfoyle and Mallory—the two best men we've got." The Sergeant smiled with a kind of cruel satisfaction. "She won't get away. And she won't pull anything, either." [25]

    "And have you extended your attention to Doctor Von Blon, by any chance?" negligently asked Vance. Again Heath's canny smile appeared.

    "He's been tailed ever since Rex was shot."

    Vance regarded him admiringly.

    "I'm becoming positively fond of you, Sergeant," he said; and beneath his chaffing note was the ring of sincerity.

    O'Brien leaned ponderously over the table and brushing the ashes from his cigar, fixed a sullen look on the District Attorney.

    "What was this story you gave out to the papers, Mr. Markham? You seemed to want to imply that the old woman took the strychnine herself. Was that hogwash, or was there something in it?"

    "I'm afraid there was nothing in it, Inspector." Markham spoke with a sense of genuine regret. "Such a theory doesn't square with the poisoning of Ada—or with any of the rest of it, for that matter."

    "I'm not so sure," retorted O'Brien. "Moran here has told me that you fellows had an idea the old woman was faking her paralysis." He rearranged his arms on the table and pointed a short, thick finger at Markham. "Supposing she shot three of the children, using up all the cartridges in the revolver, and then stole the two doses of poison—one for each of the two girls left; and then supposing she gave the morphine to the younger one, and had only one dose left..." He paused and squinted significantly.

    "I see what you mean," said Markham. "Your theory is that she didn't count on our having a doctor handy to save Ada's life, and that, having failed to put Ada out of the way, she figured the game was up and took the strychnine."

    "That's it!" O'Brien struck the table with his fist. "And it makes sense. Furthermore, it means we've cleared up the case—see?"

    "Yes, it unquestionably makes sense." It was Vance's quiet, drawling voice that answered. "But forgive me if I suggest that it fits the facts much too tidily. It's a perfect theory, don't y' know; it leaps to the brain, almost as though someone had planned it for our benefit. I rather fancy that we're intended to adopt that very logical and sensible point of view. But really now, Inspector, Mrs. Greene was not the suicidal type, however murderous she may have been."

    While Vance was speaking, Heath had left the room. A few minutes later he returned and interrupted O'Brien in a long, ill-natured defence of his suicide theory.

    "We haven't got to argue any more along that line," he announced. "I've just had Doc Doremus on the phone. He's finished the autopsy; and he says that the old lady's leg muscles had wasted away—gone plumb flabby—and that there wasn't a chance in the world of her moving her legs, let alone walking on 'em."

    "Good God!" Moran was the first to recover from the amazement this news had caused us. "Who was it, then, that Ada saw in the hall?"

    "That's just it!" Vance spoke hurriedly, trying to stem his rising sense of excitation. "If only we knew! That's the answer to the whole problem. It may not have been the murderer; but the person who sat in that library night after night and read strange books by candle light is the key to everything..."

    "But Ada was so positive in her identification," objected Markham, in a bewildered tone.

    "She's hardly to be blamed in the circumstances," Vance returned. "The child had been through a frightful experience and was scarcely normal. And it is not at all unlikely that she, too, suspected her mother. If she did, what would have been more natural than for her to imagine that this shadowy figure she saw in the hall long after midnight was the actual object of her dread? It is not unusual for a person under the stress of fright to distort an object by the projection of a dominating mental image."

    "You mean," said Heath, "that she saw somebody else, and imagined it was her mother because she was thinking so hard of the old woman?"

    "It's by no means improbable."

    "Still, there was that detail of the Oriental shawl," objected Markham. "Ada might easily have mistaken the person's features, but her insistence on having seen that particular shawl was fairly definite."

    Vance gave a perplexed nod.

    "The point is well taken. And it may prove the Ariadne's clue that will lead us out of this Cretan labyrinth. We must find out more about that shawl."

    Heath had taken out his note-book and was turning the pages with scowling concentration.

    "And don't forget, Mr. Vance," he said, without looking up, "about that diagram Ada found in the rear of the hall near the library door. Maybe this person in the shawl was the one who'd dropped it, and was going to the library to look for it, but got scared off when she saw Ada."

    "But whoever shot Rex," said Markham, "evidently stole the paper from him, and therefore wouldn't be worrying about it."

    "I guess that's right," Heath admitted reluctantly.

    "Such speculation is futile," commented Vance. "This affair is too complicated to be untangled by the unravelling of details. We must determine, if possible, who it was that Ada saw that night. Then we'll have opened a main artery of inquiry."

    "How are we going to find that out," demanded O'Brien, "when Ada was the only person who saw this woman in Mrs. Greene's shawl?"

    "Your question contains the answer, Inspector. We must see Ada again and try and counteract the suggestion of her own fears. When we explain that it couldn't have been her mother, she may recall some other point that will put us on the right track."

    And this was the course taken. When the conference ended, O'Brien departed, and the rest of us dined at the club. At half-past eight we were on our way to the Greene mansion.

    We found Ada and the cook alone in the drawing-room. The girl sat before the fire, a copy of Grimms' "Fairy Tales" turned face down on her knees; and Mrs. Mannheim, busy with a lapful of mending, occupied a straight chair near the door. It was a curious sight, in view of the formal correctness of the house, and it brought forcibly to my mind how fear and adversity inevitably level all social standards.

    When we entered the room Mrs. Mannheim rose, and gathering up her mending, started to go. But Vance indicated that she was to remain, and without a word she resumed her seat.

    "We're here to annoy you again, Ada," said Vance, assuming the rôle of interrogator. "But you're about the only person we can come to for help." His smile put the girl at ease, and he continued gently: "We want to talk to you about what you told us the other afternoon..."

    Her eyes opened wide, and she waited in a kind of awed silence.

    "You told us you thought you had seen your mother—"

    "I did see her—I did!"

    Vance shook his head. "No; it was not your mother. She was unable to walk, Ada. She was truly and helplessly paralyzed. It was impossible for her even to make the slightest movement with either leg."

    "But—I don't understand." There was more than bewilderment in her voice: there was terror and alarm as one might experience at the thought of supernatural malignancy. "I heard Doctor Von Blon tell mother he was bringing a specialist to see her this morning. But she died last night— so how could you know? Oh, you must be mistaken. I saw her—I know I saw her."

    She seemed to be battling desperately for the preservation of her sanity. But Vance again shook his head.

    "Doctor Oppenheimer did not examine your mother," he said. "But Doctor Doremus did—to-day. And he found that she had been unable to move for many years."

    "Oh!" The exclamation was only breathed. The girl seemed incapable of speech.

    "And what we've come for," continued Vance, "is to ask you to recall that night, and see if you cannot remember something—some little thing—that will help us. You saw this person only by the flickering light of a match. You might easily have made a mistake."

    "But how could I? I was so close to her."

    "Before you woke up that night and felt hungry, had you been dreaming of your mother?"

    She hesitated and shuddered slightly.

    "I don't know, but I've dreamed of mother constantly—awful, scarey dreams—ever since that first night when somebody came into my room..."

    "That may account for the mistake you made." Vance paused a moment and then asked: "Do you distinctly remember seeing your mother's Oriental shawl on the person in the hall that night?"

    "Oh, yes," she said, after a slight hesitation. "It was the first thing I noticed. Then I saw her face..."

    A trivial but startling thing happened at this moment. We had our back to Mrs. Mannheim and, for the time being, had forgotten her presence in the room. Suddenly what sounded like a dry sob broke from her, and the sewing-basket on her knees fell to the floor. Instinctively we turned. The woman was staring at us glassily.

    "What difference does it make who she saw?" she asked in a dead, monotonous voice. "She maybe saw me."

    "Nonsense, Gertrude," Ada said quickly. "It wasn't you."

    Vance was watching the woman with a puzzled expression.

    Do you ever wear Mrs. Greene's shawl, Frau Mannheim?"

    "Of course she doesn't," Ada cut in.

    "And did you ever steal into the library and read after the household is asleep?" pursued Vance.

    The woman picked up her sewing morosely, and again lapsed into sullen silence. Vance studied her a moment and then turned back to Ada.

    "Do you know of anyone who might have been wearing your mother's shawl that night?"

    "I—don't know," the girl stammered, her lips trembling.

    "Come; that won't do." Vance spoke with some asperity. "This isn't the time to shield anyone. Who was in the habit of using the shawl?"

    "No one was in the habit..." She stopped and gave Vance a pleading look; but he was obdurate.

    "Who, then, besides your mother ever wore it?"

    "But I would have known if it had been Sibella I saw—"

    "Sibella? She sometimes borrowed the shawl?"

    Ada nodded reluctantly. "Once in a great while. She—she admired the shawl... Oh, why do you make me tell you this!"

    "And you have never seen anyone else with it on?"

    "No; no one ever wore it except mother and Sibella."

    Vance attempted to banish her obvious distress with a whimsical reassuring smile.

    "Just see how foolish all your fears have been," he said lightly. "You probably saw your sister in the hall that night, and, because you'd been having bad dreams about your mother, you thought it was she. As a result, you became frightened, and locked yourself up and worried. It was rather silly, what?"

    A little later we took our leave.

    "It has always been my contention," remarked Inspector Moran, as we rode down-town, "that any identification under strain or excitement is worthless. And here we have a glaring instance of it."

    "I'd like a nice quiet little chat with Sibella," mumbled Heath, busy with his own thoughts.

    "It wouldn't comfort you, Sergeant," Vance told him. "At the end of your tête-à-tête you'd know only what the young lady wanted you to know."

    "Where do we stand now?" asked Markham, after a silence.

    "Exactly where we stood before," answered Vance dejectedly, "in the midst of an impenetrable fog.— And I'm not in the least convinced," he added, "that it was Sibella whom Ada saw in the hall."

    Markham looked amazed.

    "Then who, in Heaven's name, was it?"

    Vance sighed gloomily. "Give me the answer to that one question, and I'll complete the saga."

    That night Vance sat up until nearly two o'clock writing at his desk in the library.