The place had already begun to fill. There were at least a hundred "members" playing at the various tables and standing chatting in small groups. There was a gala, colorful atmosphere in the great room, coupled with a tinge of excitement and tension. The Japanese orderlies, in native costume, were darting about noiselessly on their various errands; and on either side of the arched entrance stood two uniformed attendants. No movement, however innocent, of any person escaped the ever-watchful eyes of these sentinels. It was a fashionable gathering; and I had no difficulty in identifying many prominent persons from social and financial circles.

    Lynn Llewellyn was still sitting in a corner of the lounge, busily engaged with pencil and note-book and apparently oblivious to all the activity going on about him.

    Vance strolled down the length of the room, greeting a few acquaintances on his way. He paused at the chuck-a-luck table near the east front window and bought a stack of chips. These he wagered on the "one," doubling each time up to five, and then beginning again. It was incredible how many "ones" showed up on the dice in the cage; and after fifteen minutes Vance had won nearly a thousand dollars. He seemed restless, though, and took his winnings indifferently.

    Turning again to the centre of the room he walked to the roulette table operated by Bloodgood. He looked on for several turns of the wheel from behind a chair, and then sat down to join the play. He was facing the lounge alcove, and as he took his place at the table he glanced casually in that direction and let his eyes rest for a moment on Llewellyn, who was still deep in thought.

    The selections for the next turn of the wheel had been made,—there were only five or six players engaged at the time,—and Bloodgood stood with the ball poised against his middle finger in the trough of the bowl, ready to project it on its indeterminate convolutions. But for some reason he did not flip it at once.

    "Faites votre jeu, monsieur," he called in a facetious sing-song, looking directly at Vance.

    Vance turned his head quickly and met the slightly cynical smile on Bloodgood's heavy lips.

    "Thanks awfully for the personal signal," he said, with exaggerated graciousness; and, leaning far up the table toward the wheel, he placed a hundred-dollar bill on the green area marked "0" at the head of the three columns of figures. "My system tells me to play the 'house number' tonight."

    The faint smile on Bloodgood's lips faded, and his eyebrows went up a trifle. Then he spun the wheel dexterously.

    It was a long play, for the ball had been given a terrific impetus and it danced back and forth for some time between the grooved wheel and the sides of the bowl. At length it seemed to settle in one of the numbered compartments, though the wheel was still spinning too rapidly to permit the reading of the numerals; but it leaped out again, made one or two gyrations, and finally came to rest in the green slot—the "house number."

    A hum went up round the table as the rake gathered in all the other stakes; but though I watched Bloodgood's face closely, I could not detect the slightest change of expression:—he was the perfect unemotional croupier.

    "Your system seems to be working," he remarked to Vance, as he moved out a stack of thirty-five yellow chips. "Vous vous engagez, et puis vous voyez. . . . Mais, qu'est-ce que vous espérez voir, monsieur?"

    "I haven't the groggiest notion," returned Vance, gathering up his bill and the chips. "I'm not hopin'—I'm driftin'."

    "In any event, you're lucky tonight," smiled Bloodgood.

    "I wonder. . . ." Vance slid his winnings into his pocket and turned from the table.

    He walked slowly toward the card room, paused at the entrance, and then moved on to the vingt-et-un game which was in progress at a high semi-circular table only a few yards from the lounge alcove. There were two vacant chairs facing the hallway; but Vance waited. The dealer sat on a small raised platform, and when the player at his right relinquished his seat Vance took the vacant chair. I noted that from this position he had an unobstructed view of Llewellyn.

    He placed a yellow chip on the paneled section of the table in front of him, and a closed card was dealt to him. He glanced at it: standing behind him, I saw that it was the ace of clubs. The next card dealt him was another ace.

    "Fancy that, Van," he remarked to me over his shoulder. "The 'ones' are followin' me around tonight."

    He turned up his first ace and laid the other beside it, placing another yellow chip on it. He was the last to be served by the dealer on the "draw"; and to my astonishment he drew two face cards—a knave and a queen. This combination of an ace and a face card constitutes a "natural"—the highest hand in black-jack—and Vance had drawn two of them on the one deal. The dealer's cards totalled nineteen.

    Vance was about to wager a second hand when Llewellyn rose with determination from his seat in the corner of the lounge and approached Bloodgood's roulette table, with note-book in hand. Instead of continuing the play, Vance again took up his winnings, slid from his high chair, and sauntered back to the centre of the room, taking his place behind the row of chairs on the side of the roulette table opposite to that at which Llewellyn had seated himself.

    Lynn Llewellyn was of medium height and slender, with a suggestion of quick wiry strength. His eyes were a flat, dull blue, and though they moved quickly, they showed no animation. His mouth, however, was emotional and mobile. His thin, somewhat haggard face gave one the impression of weakness coupled with cunning; yet withal it was a capable face—a face which a certain type of woman would consider handsome.

    When he had taken his seat he looked about him swiftly, nodded to Bloodgood and to others present, but apparently did not see Vance, although Vance stood directly across the table. He watched the play for several minutes, making a notation of the winning numbers in the leather-bound booklet he had placed before him on the table. After five or six plays, he began to frown, and, turning in his chair, summoned one of the Japanese boys who was passing.

    "Scotch," he ordered; "with plain water on the side."

    While the drink was being fetched he continued his notations. At length, when three numbers in the same column had come in succession, he began eagerly to play. When the boy brought the Scotch he waved it brusquely away, and concentrated on the game.

    For the first half-hour that we stood watching him I tried to trace some mathematical sequence in his choice of numbers, but, meeting with no success, I gave it up. I later learned that Llewellyn was playing a curious and, according to Vance, a wholly inconsistent and contradictory variation of the Labouchère—or, as it is popularly called, Labby—system which, for many years, was thoroughly tested at Monte Carlo.

    But, however inadequate the system may have been scientifically, Llewellyn was profiting by it. Indeed, had he followed up his advantages, after the unreasoned custom of the amateur player, he would, as it happened, have progressed more rapidly. But each time he caught a number (en plein) or a half-number (à cheval) or a quarter-number (en carré) he withdrew his winnings in proportion to their duplication, multiplying only when luck went against him. After almost every play he glanced quickly at the carefully ruled tables and columns of figures in his book; and it was obvious that, despite all temptation to do otherwise, he was abiding rigidly by the set formula he had decided to follow.

    Shortly after midnight, when one of his suites of doubling had reached its peak, the right number came. The result was a large winning, and when he had drawn down the six piles of yellow chips, he took a deep tremulous breath and leaned back in his chair. I calculated roughly that he was approximately ten thousand dollars ahead at this point. News of his luck soon spread to the other players in the room, and there was a general gathering of the curious around Bloodgood's table.

    I glanced about me and noted the various expressions of the spectators: some were cynical, some envious, some merely interested. Bloodgood himself showed no indication, either by a look or an intonation of voice, that anything unusual was taking place. He was the faultless automaton, discharging his duties with detached mechanical precision.

    When Llewellyn relaxed in his seat after this coup he glanced up, and, catching sight of Vance, bowed abstractedly. He was still busy with his calculations and computations, noting each turn of the wheel, and recording the winning number in his book. His face had become flushed, and his lips moved nervously as he jotted down the figures. His hands trembled perceptibly, and every few moments he took a long deep inhalation, as if trying to calm his nerves. Once or twice I noticed that he threw his left shoulder forward and bent his head to the left, like a man with angina pectoris trying to relieve the pain over his heart.

    After the sixth play had passed, Llewellyn leaned over and continued his careful system of selecting and pyramiding. This time I noticed that he introduced some new variations into his method. He did what is known as "covering" his bets, by setting the even-money black and red fields against the color of the number he chose, and by opposing the première, milieu, or dernière douzaine against the particular group of twelve in which he had made his en plein numerical choice, as well as by utilizing both the odd and even fields (pair and impair), and the high and low field (passe and manque), in the same manner.

    "That byplay," Vance whispered in my ear, "is not on the books. He's losing his nerve, and is toying with both the d'Alembert and the Montant Belge systems. But it really doesn't matter in the least. If he's lucky he'll win anyway; if he's not, he'll lose. Systems are for optimists and dreamers. The immutable fact remains that the house pays thirty-five to one against thirty-six possibilities and an added house number. That's destiny—no one can conquer it."

    But Llewellyn's luck at roulette was evidently running in his favor that night, for it was but a short time before he won again on a pyramided number. When he drew the chips to him his hands shook so that he upset one of the stacks and had difficulty in reassembling it. Again he sank back in his chair and let the next plays pass. His color had deepened; his eyes took on an unnatural glitter; and the muscles of his face began to twitch. He gazed about him blankly and missed one of the numbers that had shown on the wheel, so that he had to ask Bloodgood for it in order to keep the entries in his book complete.

    A tension had taken hold of the spectators. A strange lull replaced the general conversation. Every one seemed intent on the outcome of this age-old conflict between a man and the unfathomed laws of probability. Llewellyn sat there with a fortune in chips piled up in front of him. A few more thousand dollars and the bank would be "broken"; for Kinkaid had set a nightly capital of forty thousand dollars for this table.

    During the electrified silence that had suddenly settled over the room, broken only by the whirr of the spinning ball, the clink of chips and the droning voice of Bloodgood, Kinkaid emerged from his office and approached the table. He halted beside Vance, and indifferently watched the play for a while.

    "This is evidently Lynn's night," he remarked casually.

    "Yes, yes—quite." Vance did not take his eyes from the nervous trembling figure of Llewellyn.

    At this moment Llewellyn again caught an en plein, but he had only a single chip on the number. However, it marked the end of some mathematical cycle, according to his confused system; and, withdrawing his chips, he leaned back once more. He was breathing heavily, as if he could not get sufficient air into his lungs; and again he thrust his left shoulder forward.

    A Japanese boy was passing, and Llewellyn hailed him.

    "Scotch," he ordered again, and, with apparent effort, jotted down the winning number in his book.

    "Has he been drinking much tonight?" Kinkaid asked Vance.

    "He ordered one drink some time ago but didn't take it," Vance told him. "This will be his first, as far as I know."

    A few minutes later the boy set down beside Llewellyn a small silver tray holding a glass of whisky, an empty glass and a small bottle of charged water. Bloodgood had just spun the wheel, and he glanced at the tray.

    "Mori!" he called to the boy. "Mr. Llewellyn takes plain water."

    The Japanese turned back, set the whisky on the table before Llewellyn, and, taking up the tray with the charged water, moved away. As he came round the end of the table, Kinkaid beckoned to him.

    "You can get the plain water from my carafe in the office," he suggested.

    The boy nodded and hastened on his errand.

    "Lynn needs a drink in a hurry," Kinkaid remarked to Vance. "No use holding him up, with that crowd in the bar. . . . The damned fool! He won't have a dollar when he goes home tonight."

    As if to verify Kinkaid's prophecy, Llewellyn made a large wager and lost. As he consulted his book for the next number, the boy came up again and placed a glass of clear water beside him. Llewellyn emptied his whisky glass at one gulp and immediately drank the water. Shoving the two empty glasses to one side, he made his next play.

    Again he lost. He doubled on the following spin; and lost again. Then he redoubled, and once more he lost. He was playing Black 20 and Red 5, and on the next turn he halved his former bet between Red 21 and Black 4. "Eleven" came. He now quartered, playing 17, 18, 20 and 21 with one stack, and 4, 5, 7 and 8 with another. "Eleven" repeated.

    When Bloodgood had raked in the chips Llewellyn sat staring at the green cloth without moving. For fully five minutes he remained thus, letting the plays pass without paying any attention. Once or twice he brushed his hand across his eyes and shook his head violently, as if some confusion of mind were overpowering him.

    Vance had moved forward a step and was watching him intently, and Kinkaid, too, appeared deeply concerned about Llewellyn's behavior. Bloodgood glanced at him from time to time, but without any indication of more than a casual interest.

    Llewellyn's face had now turned scarlet, and he pressed the palms of his hands to his temples and breathed deeply, as a man will do when his head throbs with pain and he experiences a sense of suffocation.

    Suddenly, as though he were making a great effort, he sprang to his feet, upsetting his chair, and turned from the table. His hands had fallen to his sides. He took three or four steps, staggered, and then collapsed in a distorted heap on the floor.

    A slight commotion followed, and several of the men on Llewellyn's side of the table crowded about the prostrate figure. But two of the uniformed attendants at the entrance hurried forward, and, elbowing their way through the spectators, lifted Llewellyn and carried him toward Kinkaid's private office. Kinkaid was already at the door, holding it open for them when they reached it with the motionless form.

    Vance and I followed them into the office before Kinkaid had time to close the door.

    "What do you want here?" snapped Kinkaid.

    "I'm stayin' a while," Vance returned in a cold, firm voice. "Put it down to youthful curiosity—if you must have a reason."

    Kinkaid snorted and waved the two attendants out.

    "Here, Van," requested Vance; "help me lift the chap into that straight chair."

    We raised Llewellyn into the chair, and Vance held the man's body far forward so that his head hung between his knees. I noticed that Llewellyn's face had lost all its color and was now a deathly white. Vance felt for his pulse and then turned to Kinkaid, who stood rigidly by the desk, a faint cynical sneer on his mouth.

    "Any smelling salts?" Vance asked.

    Kinkaid drew out one of the desk drawers and handed Vance a squat green bottle which Vance took and held under Llewellyn's nose.

    At this moment Bloodgood opened the office door, stepped inside, and closed it quickly behind him.

    "What's the trouble?" he asked Kinkaid. There was a look of alarm on his face.

    "Get back to the table," Kinkaid ordered angrily. "There's no trouble. . . . Can't a man faint?"

    Bloodgood hesitated, shot a searching look at Vance, shrugged his shoulders, and went out.

    Vance again tried Llewellyn's pulse, forced the man's head back, and, lifting one of the eyelids, inspected the eye. Then he placed Llewellyn on the floor and slipped a flat leather cushion, from one of the chairs, under his head.

    "He hasn't fainted, Kinkaid," Vance said, rising and facing the other grimly. "He's been poisoned. . . ."

    "Rot!" The word was a guttural ejaculation.

    "Do you know a doctor in the neighborhood?" Vance's tone was significantly calm.

    Kinkaid drew in his breath audibly.

    "There's one next door. But—"

    "Get him!" commanded Vance. "And be quick about it."

    Kinkaid stood in rigid resentment for a brief moment; then he turned to the telephone on the desk and dialed a number. After a pause he cleared his throat and spoke in a strained voice.

    "Doctor Rogers? . . . This is Kinkaid. There's been an accident here. Come right away. . . . Thanks."

    He banged the receiver down and turned to Vance with a muttered oath.

    "A sweet mess!" he complained furiously.

    He stepped to a small stand beside the desk, on which stood a silver water-service, and, picking up the carafe, inverted it over one of the crystal glasses. The carafe was empty.

    "Hell!" he grumbled. He pressed a button in one of the walnut panels of the east wall. "I'm going to have a brandy. How about you?" He gave Vance a sour look.

    "Thanks awfully," murmured Vance. The door leading into the bar opened and an attendant appeared.

    "Courvoisier," Kinkaid ordered. "And fill that bottle," he added, pointing to the water-service.

    The man picked up the carafe and returned to the bar. (He had started slightly at the sight of Llewellyn's body on the floor, but by no other sign had he indicated that there was anything amiss. Kinkaid had chosen his personnel with shrewd discrimination.) When the cognac had been brought in and served, Kinkaid drank his in one swallow. Vance was still sipping his when one of the uniformed men from the reception hall below rapped on the door and admitted the doctor, a large rotund man with a benevolent, almost childlike, face.

    "There's your patient," Kinkaid rasped, jerking his thumb toward Llewellyn. "What's the verdict?"

    Doctor Rogers knelt down beside the prone figure, mumbling as he did so: "Lucky you caught me. . . . Had a confinement—just got in. . . ."

    He made a rapid examination: he looked at Llewellyn's pupils, took his pulse, put the stethoscope to his heart, and felt his wrists and the back of his neck. As he worked he asked several questions regarding what had preceded Llewellyn's present condition. It was Vance who answered all of the questions, describing Llewellyn's nervousness at the roulette table, his high color, and his sudden prostration.

    "Looks like a case of poisoning," Doctor Rogers told Kinkaid, opening his medicine case swiftly and preparing a hypodermic injection. "I can't say what it is yet. He's in a stupor. Small, accelerated pulse; rapid, shallow respiration; dilated pupils . . . all symptoms of acute toxæmia. What you tell me of the flush, the staggering and the collapse; and now the pallor—all point to some sort of poison. . . . I'm giving him a hypo of caffein. It's all I can do here. . . ." He rose ponderously and threw the syringe back into his bag. "Must get him to a hospital immediately—he needs heroic treatment. I'll call an ambulance. . . ." And he waddled to the telephone.

    Kinkaid stepped forward: he was again the cool, poker-faced gambler.

    "Get him to the nearest hospital—the best you know," he said, in a businesslike voice. "I'll take care of everything."

    Doctor Rogers nodded.

    "The Park End—it's in the neighborhood." And he began dialing a number clumsily.

    Vance moved toward the door.

    "I think I'll be staggerin' along," he drawled. His face was grim, and he gave Kinkaid a long significant look. "Interestin' letter I received—eh, what? . . . Cheerio!"

    A few minutes later we were out in 73rd Street. It was a raw cold night, and a chilling drizzle had begun to fall.

    Vance's car was parked a hundred feet or so west of the entrance to the Casino, and as we walked toward it, Detectives Snitkin and Hennessey[6] stepped out of the doorway of a near-by house.

    "Everything all right, Mr. Vance?" Snitkin asked, in a low, sepulchral voice.

    "'Pon my word!" exclaimed Vance. "What are you two gallant sleuths doing here on a night like this?"

    "Sergeant Heath[7] told us to come up here and hang around the Casino, in case you might want us," Snitkin explained. "The Sergeant said you were expecting something to break around here."

    "Really! Did he, now? Fancy that!" Vance appeared puzzled. "Stout fella, the Sergeant. . . . However, everything is taken care of. I'm dashed grateful to you for coming, but there's no earthly reason for you to hover about any longer. I'm toddlin' off to bed myself."

    But instead of going home he drove to Markham's apartment in West 11th Street.

    Markham, much to my surprise, was still up, and greeted us cordially in his drawing-room.[8] When we had settled ourselves before the gas-logs Vance turned to him with a questioning air.

    "Snitkin and Hennessey were guarding me like good fellows tonight," he said. "Do you, by any chance, ken the reason for such solicitous devotion?"

    Markham smiled, a bit shamefacedly.

    "The truth is, Vance," he apologetically explained; "after I left your apartment this afternoon I got to thinking there might be something in that letter, after all; and I called up Sergeant Heath and told him—as near as I could remember—everything that was in it. I also told him you had decided to go to the Casino tonight to watch young Llewellyn. I suppose he thought it might be just as well to send a couple of the boys up there to be on hand in case there was any truth in the letter."

    "That explains it," nodded Vance. "There was no need, however, for the bodyguard. But the letter proved amazingly prophetic."

    "What's that!" Markham swung round in his chair.

    "Yes, yes. Quite a prognosticatin' epistle." Vance took a deep draw on his cigarette. "Lynn Llewellyn was poisoned before my eyes."

    Markham sprang to his feet and stared at Vance.

    "Dead?"

    "He wasn't when I left him. But I didn't tarry." Vance was thoughtful. "He was in bad shape though. He's under the care of a Doctor Rogers at the Park End Hospital. . . . Deuced curious situation. I'm rather confused." He, too, got up. "Wait a bit." He went into the den, and I heard him at the telephone.

    In a few minutes he returned.

    "I've just talked to the pudgy Æsculapius at the hospital," he reported. "Llewellyn's about the same—except that his respiration has become slower and more shallow. His pressure is down to seventy over fifty, and he's having convulsive movements. . . . Everything's being done that's possible—adrenalin, caffein, digitalis, and gastric lavage by the nasal route. No positive diagnosis possible, of course. Very mystifyin', Markham. . . ."

    Just then the telephone rang and Markham answered it. A minute later he emerged from the den. His face was pale, and there were deep corrugations on his forehead. He came back to the centre-table, like a man in a daze.

    "Good God, Vance!" he muttered. "Something devilish is going on. That was Heath on the wire. A call has just come through to Headquarters. Heath relayed it to me—because of that letter, I imagine. . . ."

    Markham paused, looking out into space; and Vance glanced up at him curiously.

    "And what, pray, was the burden of the Sergeant's song?"

    Markham, as if with considerable effort, turned his eyes back to Vance.

    "Llewellyn's young wife is dead—poisoned!"