The Problem of the Steel Door
by Arthur B. Reeve
(from The Adventures of Craig Kennedy, Scientific Detective) 
This version of the story appeared in the Sunday edition of the Washington Post, November 24, 1912. 
It was what in college we used to call "good football weather"--a crisp autumn afternoon that sent the blood tingling through the brain and muscle. Kennedy and I were enjoying a stroll on the drive, dividing our attention between the glowing red sunset across the Hudson and the string of homeward-bound automobiles on the broad parkway. Suddenly a huge black touring car marked with big letters, "P. D. N. Y.," shot past. 
"Joy riding again in one of the city's cars," I remarked. "I thought the last police department shake-up had put a stop to that." 
"Perhaps it has," returned Kennedy. "Did you see who was in the car?" 
"No, but I see it has turned and is coming back." 
"It was Inspector--I mean First Deputy O'Connor. I thought he recognized us as he whizzed along, and I guess he did, too. Ah, congratulations, O'Connor! I haven't had a chance to tell you before now pleased I was to learn you had been appointed first deputy. It ought to have been commissioner, though," added Kennedy. 
"Congratulations nothing," rejoined O'Connor. "Just another new deal--election coming on, mayor must make a show of getting some reform done, and all that sort of thing. So he began with the police department, and here I am, first deputy. But say, Kennedy," he added, dropping his voice. "I've a little job on my mind that I'd like to pull off in about as spectacular a fashion as I--as you know how. I want to make good, conspicuously good, at the start--understand? Maybe I'll be 'broke' for it and sent to pounding the pavement of Dismissalville, but I don't care. I'll take a chance. On the level, Kennedy, it's a big thing, and it ought to be done. Will you help me put it across?" 
"What is it?" asked Kennedy with a twinkle in his eye at O'Connor's estimate of the security of his tenure of office. 
O'Connor drew us away from the automobile toward the stone parapet overlooking the railroad and river far below, and out of earshot of the department chauffeur. "I want to pull off a successful raid on the Vesper Club," he whispered earnestly, scanning our faces. 
"Good heavens, man," I ejaculated. "Don't you know that Senator Danfield is interested in--" 
"Jameson," interrupted O'Connor reproachfully, "I said 'on the level' a few minutes ago and I meant it. Senator Danfield be--well, anyhow, if I don't do it the district attorney will, with the aid of the Dowling law, and I am going to beat him to it, that's all. There's too much money being lost at the Vesper Club, anyhow. It won't hurt Danfield to be taught a lesson not to run such a phony game. I may like to put up a quiet bet myself on the ponies now and then--I won't say I don't, but this thing of Danfield's has got beyond all reason. It's the crookedest gambling joint in the city, at least judging by the stories they tell of losses there. And so beastly aristocratic, too. Read that." 
O'Connor shoved a letter into Kennedy's hand, a dainty perfumed and monogramed little missive, addressed in a feminine hand. It was such a letter as comes by the thousand to the police in the course of a year, though seldom from ladies of the smart set: 
Dear Sir: I notice in the newspapers this morning that you have just been appointed first deputy commissioner of police and that you have been ordered to suppress gambling in New York. For the love that you must still bear toward your own mother, listen to the story of a mother worn with anxiety for her only son, and if there is any justice or righteousness in this great city close a gambling hell that is sending to ruin scores of our finest young men. No doubt you know or have heard of my family--the DeLongs are not unknown in New York. Perhaps you have also heard of the losses of my son Percival at the Vesper Club. They are fast becoming the common talk of our set. I am not rich, Mr. Commissioner, in spite of our social position, but I am human, as human as a mother in any station of life, and oh, if there is any way, close up that gilded society resort that is dissipating our small fortune, ruining an only son, and slowly bringing to the grave a gray-haired widow, as worthy of protection as any mother of the poor whose plea has closed up a little poolroom or low policy shop. Sincerely,
Mrs. Julia. M. DeLong 
P.S.--Please keep this confidential--at least from my son Percival. 
"Well," said Kennedy, as he handed back the letter, "O'Connor, if you do it, I'll take back all the hard things I've ever said about the police system. Young DeLong was in one of my classes at the university, until he was expelled for that last mad prank of his. There's more to that boy than most people think, but he's the wildest scion of wealth I have ever come in contact with. How are you going to pull off your raid--is it to be down through the skylight or up from the cellar?" 
"Kennedy," replied O'Connor, in the same reproachful tone with which he had addressed me, "talk sense. I'm in earnest. You know the Vesper Club is barricaded like the National City Bank. It isn't one of those common gambling joints which depend for protection on what we call 'icebox doors.' It's proof against all the old methods. Axes and sledge hammers would make no impression there." 
"Your predecessor had some success at opening doors with a hydraulic jack, I believe, in some very difficult raids," put in Kennedy. 
"A hydraulic jack wouldn't do for the Vesper Club, I'm afraid," remarked O'Connor wearily. "Why, sir, that place has been proved bombproof--bombproof, sir. You remember recently the so-called 'gamblers' war,' in which some rivals exploded a bomb on the steps? It did more damage to the house next door than to the club. However, I can get past the outer door, I think, even if it is strong. But inside--you must have heard of it--is the famous steel door, 3 inches thick, made of armor plate. It's no use to try it at all unless we can pass that door with reasonable quickness. All the evidence we shall get will be of an innocent social clubroom downstairs. 
"The gambling is all on the second floor, beyond the door, in a room, without a window in it. Surely you've heard of that famous gambling room, with its perfect system of artificial ventilation and electric lighting that makes it rival noonday at midnight. And don't tell me I've got to get on the other side of the door by strategy, either. It is strategy-proof. The system of lookouts is perfect. No force is necessary, but it must not be destructive of life or property--or, by heaven, I'd drive up there and riddle the place with a fourteen-inch gun," exclaimed O'Connor. 
"H'm!" mused Kennedy as he flicked the ashes off his cigar and meditatively watched a passing freight train on the railroad below us. "There goes a car loaded with tons and tons of scrap iron. You want me to scrap that three-inch steel door, do you?" 
"Kennedy, I'll buy that particular scrap from you at--almost its weight in gold. The fact is, I have a secret fund at my disposal, such as former commissioners have asked for in vain. I can afford to pay you well, as well as any private client, and I hear you have had some good fees lately. Only deliver the goods." 
"No," answered Kennedy, rather piqued. "It isn't money that I am after. I merely wanted to be sure that you are in earnest. I can get you past that door as if it were made of green baize." 
It was O'Connor's turn to look incredulous, but as Kennedy apparently meant exactly what he said, he simply asked, "And will you?" 
"I will do it tonight if you say so," replied Kennedy, quietly. "Are you ready?" 
For answer, O'Connor grasped Craig's hand, as if to seal the pact. 
"All right, then," continued Kennedy. "Send a furniture van, one of those closed vans that the storage warehouses use, up to my laboratory any time before 7 o'clock. How many men will you need in the raid? Twelve? Will a van hold that many comfortably? I'll want to put some apparatus in it, but, that won't take much room." 
"Why, yes, I think so," answered O'Connor. "I'll get a well-padded van so that they won't be badly jolted by the ride down town. By George! Kennedy, I see you know more of that side of police strategy than I gave you credit for." 
"Then have the men drop into my laboratory singly about the same time. You can arrange that so that it will not look suspicious, so far uptown. It will be dark, anyhow. Perhaps, O'Connor, you can make up as the driver yourself--anyhow, get one you can trust absolutely. Then have the van down near the corner of Broadway below the club, driving slowly along about the time the theater crowd is out. Leave the rest to me. I will give you or the driver orders when the time comes." 
As O'Connor thanked Craig, he remarked, without a shade of insincerity, "Kennedy, talk about being commissioner, you ought to be commissioner." 
"Wait till I deliver the goods," answered Craig, simply. "I may fall down and bring you nothing but a lawsuit for damages for unlawful entry or unjust persecution, or whatever they call it." 
"I'll take a chance at that," called back O'Connor as he jumped into his car and directed, "Headquarters, quick." 
As the car disappeared, Kennedy filled his lungs with air as if reluctant to leave the drive. "Our constitutional," he remarked, "is abruptly at an end, Walter." 
Then he laughed, as he looked about him. 
"What a place in which to plot a raid on Danfield's Vesper Club! Why the nursemaids have hardly got the children all in for supper and bed. It's incongruous. Well, I must go over to the laboratory and get some things ready to put in that van with the men. Meet me about 7:30, Walter, up in the room all togged up. We'll dine at the Café Riviera tonight in style. And, by the way, you're quite a man about town--you must know some one who can introduce us into the Vesper Club." 
"But, Craig," I demurred, "if there is any rough work as a result, it might queer me with them. They might object to my being used--" 
"Oh, that will be all right. I just want to look the place over and lose a few chips in a good cause. No, it won't queer any of your Globe connections. We'll be on the outside when the time comes for anything to happen. In fact, I shouldn't wonder if your story would make you all the more solid with the sports. I take all the responsibility; you can have the glory. You know they like to hear the inside gossip of such things, after the event. Try it. Remember, at 7:30. We'll be a little late at dinner, but never mind; it will be early enough for the club." 
Left to my own devices I determined to do a little detective work on my own account, and not only did I succeed in finding an acquaintance who agreed to introduce us at the Vesper Club that night about 9 o'clock, but I also learned that Percival DeLong was certain to be there that night, too. I was necessarily vague about Kennedy, for fear my friend might have heard of some of his exploits, but fortunately he did not prove inquisitive. 
I hurried back to our apartment and was in the process of transforming myself into a full-fledged boulevardier, when Kennedy arrived in an extremely cheerful frame of mind. So far, his preparations had progressed very favorably, I guessed, and I was quite elated when he complimented me on what I had accomplished in the meantime. 
"Pretty tough for the fellows who are condemned to ride around in that van for four mortal hours, though," he said as he hurried into his evening clothes, "but they won't be riding all the time. The driver will make frequent stops." 
I was so busy that I paid little attention to him until he had nearly completed his toilet. I gave a gasp. 
"Why, whatever are you doing?" I exclaimed as I glanced into his room. 
There stood Kennedy, arrayed in all the glory of a sharp-pointed mustache and a goatee. He had put on evening clothes of decidedly Parisian cut, clothes which he had used abroad and had brought back with him, but which I had never know him to wear since he came back. On a chair reposed a chimney-pot hat that would have been pronounced faultless on the "continent," but was unknown, except among impresarios, on Broadway. 
Kennedy shrugged his shoulders--he even had the shrug. 
"Figure to yourself, monsieur," he said. "Ze great Kennedy, ze detectif Americain--to put it tersely in our own vernacular, wouldn't it be a fool thing for me to appear at the Vesper Club, where I should surely be recognized by some one if I went in my ordinary clothes and features? Un faux pas, at the start! Jamais!" 
There was nothing to do but agree, and I was glad that I had been discreetly reticent about my companion in talking with the friend who was to gain us entrance to the Avernus beyond the steel door. 
We met my friend at the Riviera and dined sumptuously. Fortunately, he seemed decidedly impressed with my friend, Monsieur Kay--I could do no better on the spur of the moment than take Kennedy's initial, which seemed to serve. We progressed amicably from oysters and soup down to coffee, cigars and liqueurs, and I succeeded in swallowing Kennedy's tales of Monte Carlo and Ostend and Ascot without even a smile. He must have heard them somewhere, and treasured them up for just such an occasion, but he told them in a manner that was verisimilitude itself, using perfect English with just the trace of an accent at the right places. 
At last it was time to saunter around to the Vesper Club without seeming to be too indecently early. The theaters were not yet out, but my friend said play was just beginning at the club, and would soon be in full swing. 
I had a keen sense of wickedness as we mounted the steps in the yellow flare of the flaming arc-light on the Broadway corner not far below us. A heavy, grated door swung open at the practiced signal of my friend, and as an obsequious negro servant stood bowing and pronouncing his name in the somber mahogany portal beyond, with its green marble pillars and handsome decorations. A short parley followed, after which we entered, my friend having apparently satisfied some one that we were all right. 
We did not stop to examine the first floor, which doubtless was important enough, but turned quickly up a flight of stairs. At the foot of the broad staircase Kennedy paused to examine some rich carvings and I felt him nudge me. I turned. It was an inclosed staircase with walls that looked to be of reinforced concrete. Swung back on hinges like those of a modern burglar-proof safe was the famous steel door. 
We did not wish to appear to be too interested, yet a certain amount of curiosity was quite proper. 
My friend paused on the steps, turned, and came back. 
"You're perfectly safe," he smiled, tapping the door with his cane with a sort of affectionate respect. "It would take the police ages to get past that barrier, which would be swung shut and bolted the moment the lookout gave the alarm. But there has never been any trouble. The police know that it is so far, no farther. Besides," he added with a wink to me, "you know Senator Danfield would not like this pretty little door even scratched. Come up, I think I hear DeLong's voice upstairs. You've heard of him, monsieur? It's said his luck has changed. I'm anxious to find out." 
Quickly he led the way up the handsome staircase and into a large, lofty, richly furnished room. Everywhere there were thick, heavy carpets on the floor, into which your feet sank with an air of satisfying luxury. 
The room into which we entered was indeed absolutely windowless. It was a room built within the original room of the old house. Thus the windows overlooking the street from the second floor in reality bore no relation to it. For light it depended on a complete oval of lights overhead, so arranged as to be themselves invisible, but shining through richly stained glass and conveying the illusion of a slightly clouded noon-day. The absence of windows was made up for, as I learned later, by a ventilating device so perfect that, although every one was smoking, a most fastidious person could scarcely have been offended by the odor of tobacco. 
Of course, I did not notice all this at first. What I did notice, however, was a faro layout and a hazard board, but as no one was playing at either, my eye quickly traveled to a roulette table which stretched along the middle of the room. Some ten or a dozen men in evening clothes were gathered watching with intent faces the spinning wheel. There was no money on the table, nothing but piles of chips of various denominations. Another thing that surprised me as I looked was that the tense look on the faces of the players was anything but the feverish, haggard gaze I had expected. In fact, they were sleek, well-fed, typical prosperous New Yorkers, rather inclined to the noticeable in dress, and carrying their avoirdupois as if life was an easy game with them. Most of them evidently belonged to the financial and society classes. There were no tragedies; the tragedies were elsewhere--in their offices, homes, in the courts, anywhere, but not here at the club. Here all was life, light, and laughter. 
As we advanced, we heard only the rattle of the ball, the click of the chips, and the monotonous tone of the spinner. "Twenty-three, black. Eight, red. Seventeen, black." It was almost like the boys in a broker's office calling off the quotations of the ticker and marking them up on the board. 
Looking forward, almost oblivious to the rest, was Percival DeLong, a tall, lithe, handsome young man, whose boyish face ill comported with the marks of dissipation clearly outlined on it. Such a boy, it flashed across my mind, ought to be studying the possible plays of football of an evening in the field house after his dinner at the training table, rather than the possible gyrations of the little platinum ball on the wheel. 
"Curse the luck!" he exclaimed, as "17" appeared again. 
A Hebrew banker staked a pile of chips on the "17" to come up a third time. A murmur of applause at his nerve ran through the circle. DeLong hesitated, as one who thought, "Seventeen has come out twice-- the odds against its coming again are too great, even though the winnings would be fabulous for a good stake." He placed his next bet on another number. 
"He's playing Lord Rosslyn's system tonight," whispered my friend. 
The wheel spun, the ball rolled, and the croupier called again, "Seventeen, black." A tremor of excitement ran through the crowd. It was almost unprecedented. 
DeLong, with a stifled oath, leaned back and scanned the faces about the table. 
"And '17' has precisely the same chance of turning up in the next spin as if it had not already had a run of three," said a voice at my elbow. 
It was Kennedy. The roulette table needs no introduction when curious sequences are afoot. All are friends. 
"That's the theory of Sir Hiram Maxim," commented my friend, as he excused himself reluctantly for another appointment. "But no true gambler will believe it, monsieur, or at least act on it." 
All eyes were turned on Kennedy, who made a gesture of polite deprecation, as if the remark of my friend were true, but--he nonchalantly placed his chips on the "17." 
"The odds against '17' appearing four consecutive times are some millions," he went on, "and yet, having appeared three times, it is just as likely to appear again as before. It is the usual practice to avoid a number that has had a run, on the theory that some other number is more likely to come up than it is. That would be the case if it were drawing balls from a bag full of red and black balls--the more red ones drawn the smaller the chances of drawing another red one. But if the balls are put back in the bag after being drawn the chances of drawing a red one after three have been drawn are exactly the same as ever." 
"You talk like a professor I had at the university," ejaculated DeLong contemptuously as Craig finished his disquisition on the practical fallibility of theoretically infallible systems. Again DeLong carefully avoided the '17,' as well as the black. 
The wheel spun again; the ball rolled. The knot of spectators around the table watched with bated breath. 
Seventeen won! 
As Kennedy piled up his winnings superciliously, without even the appearance of triumph, a man behind me whispered, "A foreign nobleman with a system--watch him. 
"Non, monsieur," said Kennedy quickly, having overheard the remark, no system, sir. There is only one system of which I know." 
"What?" asked DeLong eagerly. 
Kennedy staked a large sum on the red to win. The black came up, and he lost. He doubled the stake and played again, and again lost. With amazing calmness Craig kept right on doubling. "The martingale," I heard the man whisper behind me. "In other words, double or quit." 
Kennedy was now in for some hundreds, a sum that was sufficiently large for him, but he doubled again, still cheerfully playing the red, and the red won. As he gathered up his chips he rose. 
"That's the only system," he said simply. 
"But go on, go on," came the chorus from about the table. 
"No," said Kennedy quietly, "that is part of the system, too--to quit when you have won back your stakes and a little more." 
"Huh!" exclaimed DeLong in disgust. "Suppose you were in for some thousands--you wouldn't quit. If you had real sporting blood you wouldn't quit anyhow." 
Kennedy calmly passed over the open insult, letting it be understood that he ignored this beardless youth. 
"There is no way you can beat the game in the long run if you keep at it," he answered simply. "It is mathematically impossible. It is not a game of chance for the bank--ah, it is exact, mathematical--c'est une question d'arithmetique, seulement, n'est-ce pas, messieurs?" 
"Perhaps," admitted DeLong, "but it doesn't explain why I am losing tonight while every one else is winning." 
"We are not winning," persisted Craig. "After I have had a bite to eat I will demonstrate how to lose--by keeping on playing." He led the way to the café. 
DeLong was too intent on the game to leave, even for refreshments. Now and then I saw him beckon to an attendant, who brought him a stiff drink of whisky. For a moment his play seemed a little better, then he would drop back into his hopeless losing. For some reason or other his "system" failed absolutely. 
"You see, it's hopeless," mused Kennedy over our light repast. "And yet of all the gambling games roulette offers the players the best odds, far better than horse racing, for instance. Our method has usually been to outlaw roulette and permit horse racing: in other words suppress the more favorable and permit the less favorable. However, we're doing better now: we're suppressing both. Of course, what I say applies only to roulette when it is honestly played--DeLong would lose anyhow, I fear." 
I started at Kennedy's tone and whispered, hastily: "What do you mean? Do you think the wheel is crooked?" 
"I haven't a doubt of it," he replied in an undertone. "The run of '17' might happen--yes. But it is improbable. They let me win because I was a new player--new players always win at first. It is proverbial, but the man who is running this game has made it look like a platitude. To satisfy myself on that point I am going to play again--until I have lost my winnings and am just square with the game. When I reach the point that I am convinced that some crooked work is going on I am going to try a little experiment. Walter, I want you to stand close to me so that no one can see what I am doing. Do just as I will indicate to you." 
The gambling room was now fast filling up with the first of the theater crowd. DeLong's table was the center of attraction, owing to the high play. A group of young men of his set were commiserating with him on his luck and discussing it with the finished air of roués of double their age. He was doggedly following his system. 
Kennedy and I approached. 
"Ah, here is the philosophical stranger again," DeLong exclaimed, catching sight of Kennedy. "Perhaps he can enlighten us on how to win at roulette by playing his own system." 
"Au contraire, monsieur, let me demonstrate how to lose," answered Craig with a smile that showed a row of faultless teeth beneath his black mustache, decidedly foreign. 
Kennedy played and lost, and lost again; then he won, but in the main he lost. After one particularly large loss I felt his arm on mine, drawing me closely to him. DeLong had taken a sort of grim pleasure in the fact that Kennedy, too, was losing. I found that Craig had paused in his play at the moment when DeLong had staked a large sum that a number below "18" would turn up--for five plays the numbers had been between "18" and "36." Curious to see what Craig was doing, I looked cautiously down between us. All eyes were fixed on the wheel. Kennedy was holding up an ordinary compass in the crooked-up palm of his hand. The needle pointed at me, as I happened to be standing north of it. 
The wheel spun. Suddenly the needle swung around to a point between the north and south poles, quivered a moment, and came to rest in that position. Then it swung back north. 
It was some seconds before I realized the significance of it. It had pointed at the table--and DeLong had lost again. There was some electric attachment at work. 
Kennedy and I exchanged glances, and he shoved the compass into my hand quickly. "You watch it, Walter, while I play," he whispered. 
Carefully concealing it, as he had done, yet holding it as close to the table as I dared, I tried to follow two things at once without betraying myself. As near as I could make out, something happened at every play. I would not go so far as to assert that whenever the larger stakes were on a certain number the needle pointed to the opposite side of the wheel, for it was impossible to be at all accurate about it. Once I noticed the needle did not move at all, and he won. But on the next play he staked what I knew must be the remainder of his winnings on what seemed a very good chance. Even before the wheel was revolved and the ball set rolling, the needle swung about, and when the platinum came to rest Kennedy rose from the table, a loser. 
"By George, though," exclaimed DeLong, grasping his hand. "I take it all back. You are a good loser, sir. I wish I could take it as well as you do. But then, I'm in too deeply. There are too many 'markers' with the house up against me." 
Senator Danfield had just come in to see how things were going on. He was a sleek, fat man, and it was amazing to see with what deference his victims treated him. He affected not to have heard what DeLong said, but I can imagine what he was thinking, for I had heard that he had scant sympathy with any one after he "went broke"--another evidence of the camaraderie and good-fellowship that surrounded the game. 
Kennedy's next remark surprised me. "Oh, your luck will change, D. L."--everyone referred to him as "D. L.," for gambling houses have an aversion for real names and greatly prefer initials--"your luck will change presently. Keep right on with your system. It's the best you can do tonight, short of quitting." 
"I'll never quit," replied the young man under his breath. 
Meanwhile, Kennedy and I paused on the way out to compare notes. My report of the behavior of the compass only confirmed him in his opinion. 
As we turned to the stairs we took in a full view of the room. A faro layout was purchasing Senator Danfield a new touring car every hour at the expense of the players. Another group was gathered around the hazard board, deriving evident excitement, though I am sure none could have given an intelligent account of the chances they were taking. Two roulette tables were now going full blast, the large crowd still about DeLong's. Snatches of conversation came in to us now and then, and I caught one sentence: "DeLong's in for over a hundred thousand now on the week's play, I understand. Poor boy--that about cleans him up." 
"The tragedy of it, Craig," I whispered, but he did not hear. 
With his hat tilted at a rakish angle and his opera coat over his arm, he sauntered over for a last look. 
"Any luck yet?" he asked, carelessly. 
"The devil--no," returned the boy. 
"Do you know what my advice to you is--the advice of a man who has seen high play everywhere from Monte Carlo to Shanghai?" 
"What?" 
"Play until your luck changes, if it takes until tomorrow." 
A supercilious smile crossed Senator Danfield's fat face. 
"I intend to," and the haggard young face turned again to the table and forgot us. 
"For heaven's sake, Kennedy," I gasped as we went down the stairway, "what do you mean by giving him such advice--you?" 
"Not so loud, Walter. He'd have done it anyway, I suppose, but I want him to keep at it. This night means life or death to Percival DeLong and his mother, too. Come on, let's get out of this." 
We passed the formidable steel door and gained the street, jostled by the late comers who had left the aftertheater restaurants for a few moments of play at the famous club that so long had defied the police. 
Almost gayly Kennedy swung along toward Broadway. At the corner he hesitated, glanced up and down, caught sight of the furniture van in the middle of the next block. The driver was tugging at the harnass of the horses, apparently fixing it. We walked along and stopped beside it. 
"Drive around in front of the Vesper Club slowly," said Kennedy as the driver at last looked up. 
The van lumbered ahead, and we followed it casually. Around the corner it turned. We turned also. My heart was going like a sledge hammer as the critical moment approached. My head was in a whirl. What would that gay throng back of those darkened windows down the street think if they knew what was being prepared for them? 
On, like the Trojan horse, the van lumbered. A man went into the Vesper Club, and I saw the negro at the door eye the oncoming van suspiciously. The door banged shut. 
The next thing I knew, Kennedy had ripped off his disguise, had flung himself up behind the van and had swung the doors open. A dozen men with axes and sledge hammers swarmed out and up the steps of the club. 
"Call the reserves, O'Connor," cried Kennedy. "Watch the roof and the back yard." 
The driver of the van hastened to send in the call. 
The sharp raps of the hammers and the axes sounded on the thick brass-bound oak of the outer door in thick succession. There was a scurry of feet inside, and we could hear a grating noise and a terrific jar as the inner steel door shut. 
"A raid! A raid on the Vesper Club!" shouted a belated passerby. The crowd swarmed around from Broadway, as if it were noon instead of midnight. 
Banging and ripping and tearing, the outer door was slowly forced. As it crashed in the quick gongs of several police patrols sounded. The reserves had been called out at the proper moment, too late for them to "tip off" the club that there was going to be a raid, as frequently occurs. 
Disregarding the noise behind me, I leaped through the wreckage with the other raiders. The steel door barred all further progress with its cold blue impassibility. How were we to surmount this last and most formidable barrier? 
I turned in time to see Kennedy and O'Connor hurrying up the steps with a huge tank studded with bolts like a boiler, while two other men carried a second tank. 
Out of the tanks' stout tubes led, with stopcocks and gages at the top. From a case under his arm Kennedy produced a curious arrangement like a huge book, with a curved neck and a sharp beak. Really it consisted of two metal tubes which ran into a sort of cylinder, or mixing chamber, above the nozzle, while parallel to them ran a third, separate tube with a second nozzle of its own. Quickly he joined the ends of the tubes from the tanks to the metal hook, the oxygen tank being joined to two of the tubes of the hook, and the second being joined to the other. With a match, he touched the nozzle gingerly. Instantly a blazing, spitting noise followed, and an intense blinding needle of flame. 
"Now for the oxy-acetylene blowpipe," cried Kennedy as he advanced toward the steel door. "We'll make short work of this." 
Almost as he said it, the steel beneath the blowpipe became incandescent. 
Just to test it, he cut off the head of a three-quarter-inch steel rivet--taking about a quarter of a minute to do it. It was evident, though, that that would not weaken the door appreciably, even if the rivets were all driven through. Still they gave a starting point for the flame of the high-pressure acetylene torch. 
It was a brilliant sight. The terrific heat from the first nozzle caused the metal to glow under the torch as if in an open-hearth furnace. From the second nozzle issued a stream of oxygen under which the hot metal of the door was completely consumed. The force of the blast as the compressed oxygen and acetylene were expelled carried a fine spray of the disintegrating metal visibly before it. And yet it was not a big hole that it made--scarcely an eighth of an inch wide, but clear and sharp as if a buzz-saw were eating its way through a 3-inch plank of white pine. 
With tense muscles Kennedy held this terrific engine of destruction and moved it as easily as if it had been a mere pencil of light. He was easily the calmest of us all as we crowded about him at a respectable distance. 
"Acetylene, as you may know," he hastily explained, never pausing for a moment in his work, "is composed of carbon and hydrogen. As it burns at the end of the nozzle it is broken into carbon and hydrogen--the carbon gives the high temperature, and the hydrogen forms a cone that protects the end of the blowpipe from being itself burnt up. 
"But isn't it dangerous?" I asked, amazed at the skill with which he handled the blowpipe. 
"Not particularly--when you know how to do it. In that tank is a porous asbestos packing saturated with acetone, under pressure. Thus I can carry acetylene safely, for it is dissolved, and the possibility of explosion is minimized. This mixing chamber by which I am holding the torch, where the oxygen and acetylene mix, is also designed in such a way as to prevent a flash-back. The best thing about this style of blowpipe is the ease with which it can be transported and the curious uses--like the present--to which it can be put." 
He paused a moment to test the door. All was silence on the other side. The door itself was as firm as ever. 
"Huh!" exclaimed one of the detectives behind me, "these new-fangled things ain't all they're cracked up to be. Now if I was runnin' this show I'd dynamite that door to kingdom come." 
"And wreck the building and kill a few people," I returned, hotly resenting the criticism of Kennedy. Kennedy affected not to hear. 
"When I shut off the oxygen in this second jet," he resumed as if nothing had been said, "you see the torch merely heats the steel. I can get a heat of approximately 6,300 degrees Fahrenheit, and the flame will still exert a pressure of 50 pounds to the square inch." 
"Wonderful!" exclaimed O'Connor, who had not heard the remark of his subordinate and was watching with undisguised admiration. "Kennedy, how did you ever think of such a think?" 
"Why it's used for welding, you know," answered Craig as he continued to work calmly in the growing excitement. "I first saw it in actual use in mending a cracked cylinder in an automobile. The cylinder was repaired without being taken out at all. I've seen it weld new teeth and build up old worn teeth on gearing as good as new." 
He paused to let us see the terrifically heated metal under the flame. 
"You remember when we were talking on the drive about the raid, O'Connor? A carload of scrap metal went by on the train below us. They use this blowpipe to cut it up frequently. That's what gave me the idea. See, I turn on the oxygen now in this second nozzle. The blowpipe is no longer an instrument for joining metals together, but for cutting them asunder. The steel burns just as you, perhaps, have seen a watch-spring burn in a jar of oxygen. Steel, hard or soft, tempered, annealed, chrome, harveyized, it all burns just as fast and just as easily. And it's cheap, too. This raid may cost a couple of dollars, as far as the blowpipe is concerned-quite a difference from the thousands of dollars' loss that would follow an attempt to blow the door in." 
The last remark was directed quietly at the doubting detective. He had nothing to say. We stood in awe-struck amazement as the torch slowly, inexorably, traced a thin line along the edge of the door. 
Minute after minute sped by, as the line burned by the blowpipe cut straight from top to bottom. It seemed hours to me. Was Kennedy going to slit the whole door and let it fall in with a crash? 
No, I could see that even in his cursory examination of the door he had gained a pretty good knowledge of the location of the bolts imbedded in the steel. One after another, he was cutting clear through and severing them, as with a superhuman knife. 
What was going on on the other side of the door, I wondered. I could scarcely imagine the consternation of the gamblers caught in their own trap. 
With a quick motion Kennedy turned off the acetylene and oxygen. The last bolt had been severed. A gentle push of the hand, and he swung the once impregnable door on its delicately poised hinges as easily as if he had merely said, "Open sesame." The robbers' cave yawned before us. 
We made a rush upstairs. Kennedy was first, O'Connor next, and myself scarcely a step behind, with the rest of O'Connor's men at our heels. 
I think we were all prepared for some sort of gun play, for the crooks were desperate characters, and I myself was surprised to encounter nothing but physical force, which was quickly overcome. 
In the now disordered richness of the rooms, waving his "John Doe" warrants in one hand and his pistol in the other, O'Connor shouted: "You're all under arrest, gentlemen. If you resist further it will go hard with you." 
Crowded now in one end of the room in speechless amazement was the late gay party of gamblers, including Senator Danfield himself. They had reckoned on toying with any chances but this. The pale white face of DeLong among them was like a specter, as he stood staring blankly about, and still, insanely, twisting the roulette wheel before him. 
Kennedy advanced toward the table with an ax, which he had seized from one of our men. A well-directed blow shattered the mechanism of the delicate wheel. 
"DeLong," he said, "I'm not going to talk to you like your old professor at the university, nor like your recent friend, the Frenchman with the system. This is what you have been up against, my boy. Look!" 
His forefinger indicated an ingenious, but now tangled and twisted, series of minute wires and electro-magnets in the broken wheel before us. Delicate brushes led the current into the wheel. With another blow of his ax, Craig disclosed wires running down through the leg of the table to the floor, and under the carpet to buttons operated by the man who ran the game. 
"Wh-what does it mean?" asked DeLong blankly. 
"It means that you had little enough chance to win at a straight game of roulette. But the wheel is very rarely straight, even with all the odds in favor of the bank, as they are. This game was electrically controlled. Others are mechanically controlled by what is sometimes called 'the mule's ear,' and other devices. You can't win. These wires and magnets can be made to attract the little ball into any pocket the operator desires. Each one of those pockets contains a little electro-magnet. One set of magnets in the red pockets is connected with one button under the carpet and a battery. The other set in the black pockets is connected with another button and a battery. This ball is not really of platinum. Platinum is non-magnetic. It is simply a soft iron hollow ball, plated with platinum. Whichever set of electro-magnets is energized attracts the ball and by this simple method it is in the power of the operator to let the ball go to red or black as he may wish. Other similar arrangements control the odd and even, and other combinations from other push buttons. A special arrangement took care of that '17' freak. There isn't an honest gambling machine in the whole place--I might almost say the whole city. The whole thing is crooked from start to finish--the men, the machines, the--" 
"That machine could be made to beat me by turning up a run of '17' any number of times, or red or black, or odd or even, over '18' or anything?" 
"Anything, DeLong." 
"And I never had a chance," he repeated, meditatively fingering the wires. "They broke me tonight. Danfield"--DeLong turned, looking dazedly about in the crowd for his former friend, then his hand shot into his pocket, and a little ivory-handled pistol flashed out--"Danfield, your blood is on your own head. You have ruined me." 
Kennedy must have been expecting something of the sort, for he seized the arm of the young man, weakened by dissipation, and turned the pistol upward, as if it had been in the grasp of a mere child. 
A blinding flash followed in the farthest corner of the room, and a huge puff of smoke. Before I could collect my own wits another followed in the opposite corner. The room was filled with dense smoke. 
Two men were scuffling at my feet. One was Kennedy. As I dropped down quickly to help him I saw that the other was Danfield, his face purple with the violence of the struggle. 
"Don't be alarmed, gentlemen," I heard O'Connor shout, "the explosions were only flashlights of the official police photographers. We now have the evidence complete. Gentlemen, you will now go down quietly to the patrol wagons below, two by two. If you have anything to say, say it to the magistrate of the night court." 
"Hold his arms, Walter," panted Kennedy. 
I did. With a dexterity that would have done credit to a pickpocket, Kennedy reached into Danfield's pocket and pulled out some papers. 
Before the smoke had cleared and order had been restored, Craig exclaimed: 
"Let him up, Walter. Here, DeLong: here are the I. O. U.'s against you. Tear them up--they are not even a debt of honor." 
[End.]