We stared at each other in blank awe, at the various parts, so innocent looking in the heaps on the table, now safely separated, but together a combination ticket to perdition.

"Who do you suppose could have sent it?" I blurted out when I found my voice, then, suddenly recollecting the political and legal fight that Carton was engaged in at the time, I added, "The white slavers?"

"Not a doubt," he returned laconically. "And," he exclaimed, bringing down both hands vigorously in characteristic emphasis on the arms of his office chair, "I've got to win this fight against the vice trust, as I call it, or the whole work of the district attorney's office in clearing up the city will be discredited—to say nothing of the risk the present incumbent runs at having such grateful friends about the city send marks of their affection and esteem like this."

I knew something already of the situation, and Carton continued thoughtfully: "All the powers of vice are fighting a last-ditch battle against me now. I think I am on the trail of the man or men higher up in this commercialised-vice business—and it is a business, big business, too. You know, I suppose, that they seem to have a string of hotels in the city, of the worst character. There is nothing that they will stop at to protect themselves. Why, they are using gangs of thugs to terrorise any one who informs on them. The gunmen, of course, hate a snitch worse than poison. There have been bomb outrages, too—nearly a bomb a day lately—against some of those who look shaky and seem to be likely to do business with my office. But I'm getting closer all the time."

"How do you mean?" asked Kennedy.

"Well, one of the best witnesses, if I can break him down by pressure and promises, ought to be a man named Haddon, who is running a place in the Fifties, known as the Mayfair. Haddon knows all these people. I can get him in half an hour if you think it worth while—not here, but somewhere uptown, say at the Prince Henry."

Kennedy nodded. We had heard of Haddon before, a notorious character in the white-light district. A moment later Carton had telephoned to the Mayfair and had found Haddon.

"How did you get him so that he is even considering turning state's evidence?" asked Craig.

"Well," answered Carton slowly, "I suppose it was partly through a cabaret singer and dancer, Loraine Keith, at the Mayfair. You know you never get the truth about things in the underworld except in pieces. As much as any one, I think we have been able to use her to weave a web about him. Besides, she seems to think that Haddon has treated her shamefully. According to her story, he seems to have been lavishing everything on her, but lately, for some reason, has deserted her. Still, even in her jealousy she does not accuse any other woman of winning him away."

"Perhaps it is the opposite—another man winning her," suggested Craig dryly.

"It's a peculiar situation," shrugged Carton. "There is another man. As nearly as I can make out there is a fellow named Brodie who does a dance with her. But he seems to annoy her, yet at the same time exercises a sort of fascination over her."

"Then she is dancing at the Mayfair yet?" hastily asked Craig.

"Yes. I told her to stay, not to excite suspicion."

"And Haddon knows?"

"Oh, no. But she has told us enough about him already so that we can worry him, apparently, just as what he can tell us would worry the others interested in the hotels. To tell the truth, I think she is a drug fiend. Why, my men tell me that they have seen her take just a sniff of something and change instantly—become a willing tool."

"That's the way it happens," commented Kennedy.

"Now, I'll go up there and meet Haddon," resumed Carton. "After I have been with him long enough to get into his confidence, suppose you two just happen along."

Half an hour later Kennedy and I sauntered into the Prince Henry, where Carton had made the appointment in order to avoid suspicion that might arise if he were seen with Haddon at the Mayfair.

The two men were waiting for us—Haddon, by contrast with Carton, a weak-faced, nervous man, with bulgy eyes.

"Mr. Haddon," introduced Carton, "let me present a couple of reporters from the Star—off duty, so that we can talk freely before them, I can assure you. Good fellows, too, Haddon."

The hotel and cabaret keeper smiled a sickly smile and greeted us with a covert, questioning glance.

"This attack on Mr. Carton has unnerved me," he shivered. "If any one dares to do that to him, what will they do to me?"

"Don't get cold feet, Haddon," urged Carton. "You'll be all right. I'll swing it for you."

Haddon made no reply. At length he remarked: "You'll excuse me for a moment. I must telephone to my hotel."

He entered a booth in the shadow of the back of the cafe, where there was a slot-machine pay-station. "I think Haddon has his suspicions," remarked Carton, "although he is too prudent to say anything yet."

A moment later he returned. Something seemed to have happened. He looked less nervous. His face was brighter and his eyes clearer. What was it, I wondered? Could it be that he was playing a game with Carton and had given him a double cross? I was quite surprised at his next remark.

"Carton," he said confidently, "I'll stick."

"Good," exclaimed the district attorney, as they fell into a conversation in low tones.

"By the way," drawled Kennedy, "I must telephone to the office in case they need me."

He had risen and entered the same booth.

Haddon and Carton were still talking earnestly. It was evident that, for some reason, Haddon had lost his former halting manner. Perhaps, I reasoned, the bomb episode had, after all, thrown a scare into him, and he felt that he needed protection against his own associates, who were quick to discover such dealings as Carton had forced him into. I rose and lounged back to the booth and Kennedy.

"Whom did he call?" I whispered, when Craig emerged perspiring from the booth, for I knew that that was his purpose.

Craig glanced at Haddon, who now seemed absorbed in talking to Carton. "No one," he answered quickly. "Central told me there had not been a call from this pay-station for half an hour."

"No one?" I echoed almost incredulously. "Then what did he do?
Something happened, all right."

Kennedy was evidently engrossed in his own thoughts, for he said nothing.

"Haddon says he wants to do some scouting about," announced Carton, when we rejoined them. "There are several people whom he says he might suspect. I've arranged to meet him this afternoon to get the first part of this story about the inside working of the vice trust, and he will let me know if anything develops then. You will be at your office?"

"Yes, one or the other of us," returned Craig, in a tone which Haddon could not hear.

In the meantime we took occasion to make some inquiries of our own about Haddon and Loraine Keith. They were evidently well known in the select circle in which they travelled. Haddon had many curious characteristics, chief of which to interest Kennedy was his speed mania. Time and again he had been arrested for exceeding the speed limit in taxicabs and in a car of his own, often in the past with Loraine Keith, but lately alone.

It was toward the close of the afternoon that Carton called up hurriedly. As Kennedy hung up the receiver, I read on his face that something had gone wrong.

"Haddon has disappeared," he announced, "mysteriously and suddenly, without leaving so much as a clue. It seems that he found in his office a package exactly like that which was sent to Carton earlier in the day. He didn't wait to say anything about it, but left. Carton is bringing it over here."

Perhaps a quarter of an hour later, Carton himself deposited the package on the laboratory table with an air of relief. We looked eagerly. It was addressed to Haddon at the Mayfair in the same disguised handwriting and was done up in precisely the same fashion.

"Lots of bombs are just scare bombs," observed Craig. "But you never can tell."

Again Kennedy had started to dissect.

"Ah," he went on, "this is the real thing, though, only a little different from the other. A dry battery gives a spark when the lid is slipped back. See, the explosive is in a steel pipe. Sliding the lid off is supposed to explode it. Why, there is enough explosive in this to have silenced a dozen Haddons."

"Do you think he could have been kidnapped or murdered?" I asked. "What is this, anyhow—gang-war?"

"Or perhaps bribed?" suggested Carton.

"I can't say," ruminated Kennedy. "But I can say this: that there is at large in this city a man of great mechanical skill and practical knowledge of electricity and explosives. He is trying to make sure of hiding something from exposure. We must find him."

"And especially Haddon," Carton added quickly. "He is the missing link.
His testimony is absolutely essential to the case I am building up."

"I think I shall want to observe Loraine Keith without being observed," planned Kennedy, with a hasty glance at his watch. "I think I'll drop around at this Mayfair I have heard so much about. Will you come?"

"I'd better not," refused Carton. "You know they all know me, and everything quits wherever I go. I'll see you soon."

As we drove in a cab over to the Mayfair, Kennedy said nothing. I wondered how and where Haddon had disappeared. Had the powers of evil in the city learned that he was weakening and hurried him out of the way at the last moment? Just what had Loraine Keith to do with it? Was she in any way responsible? I felt that there were, indeed, no bounds to what a jealous woman might dare.

Beside the ornate grilled doorway of the carriage entrance of the Mayfair stood a gilt-and-black easel with the words, "Tango Tea at Four." Although it was considerably after that time, there was a line of taxi-cabs before the place and, inside, a brave array of late-afternoon and early-evening revellers. The public dancing had ceased, and a cabaret had taken its place.

We entered and sat down at one of the more inconspicuous of the little round tables. On a stage, at one side, a girl was singing one of the latest syncopated airs.

"We'll just stick around a while, Walter," whispered Craig. "Perhaps this Loraine Keith will come in."

Behind us, protected both by the music and the rustle of people coming and going, a couple talked in low tones. Now and then a word floated over to me in a language which was English, sure enough, but not of a kind that I could understand.

"Dropped by a flatty," I caught once, then something about a "mouthpiece," and the "bulls," and "making a plant."

"A dip—pickpocket—and his girl, or gun-moll, as they call them," translated Kennedy. "One of their number has evidently been picked up by a detective and he looks to them for a good lawyer, or mouth-piece."

Besides these two there were innumerable other interesting glimpses into the life of this meeting-place for the half-and underworlds. A motion in the audience attracted me, as if some favourite performer were about to appear, and I heard the "gun-moll" whisper, "Loraine Keith."

There she was, a petite, dark-haired, snappy-eyed girl, chic, well groomed, and gowned so daringly that every woman in the audience envied and every man craned his neck to see her better. Loraine wore a tight-fitting black dress, slashed to the knee. In fact, everything was calculated to set her off at best advantage, and on the stage, at least, there was something recherche about her. Yet, there was also something gross about her, too.

Accompanying her was a nervous-looking fellow whose washed-out face was particularly unattractive. It seemed as if the bone in his nose was going, due to the shrinkage of the blood-vessels. Once, just before the dance began, I saw him rub something on the back of his hand, raise it to his nose, and sniff. Then he took a sip of a liqueur.

The dance began, wild from the first step, and as it developed, Kennedy leaned over and whispered, "The danse des Apaches."

It was acrobatic. The man expressed brutish passion and jealousy; the woman, affection and fear. It seemed to tell a story—the struggle of love, the love of the woman against the brutal instincts of the thug, her lover. She was terrified as well as fascinated by him in his mad temper and tremendous superhuman strength. I wondered if the dance portrayed the fact.

The music was a popular air with many rapid changes, but through all there was a constant rhythm which accorded well with the abandon of the swaying dance. Indeed, I could think of nothing so much as of Bill Sykes and Nancy as I watched these two.

It was the fight of two frenzied young animals. He would approach stealthily, seize her, and whirl her about, lifting her to his shoulder. She was agile, docile, and fearful. He untied a scarf and passed it about her; she leaned against it, and they whirled giddily about. Suddenly, it seemed that he became jealous. She would run; he follow and catch her. She would try to pacify him; he would become more enraged. The dance became faster and more furious. His violent efforts seemed to be to throw her to the floor, and her streaming hair now made it seem more like a fight than a dance. The audience hung breathless. It ended with her dropping exhausted, a proper finale to this lowest and most brutal dance.

Panting, flushed, with an unnatural light in their eyes, they descended to the audience and, scorning the roar of applause to repeat the performance, sat at a little table.

I saw a couple of girls come over toward the man.

"Give us a deck, Coke," said one, in a harsh voice.

He nodded. A silver quarter gleamed momentarily from hand to hand, and he passed to one girl stealthily a small white-paper packet. Others came to him, both men and women. It seemed to be an established thing.

"Who is that?" asked Kennedy, in a low tone, of the pickpocket back of us.

"Coke Brodie," was the laconic reply.

"A cocaine fiend?"

"Yes, and a lobbygow for the grapevine system of selling the dope under this new law."

"Where does he get the supply to sell?" asked Kennedy, casually.

The pickpocket shrugged his shoulders.

"No one knows, I suppose," Kennedy commented to me. "But he gets it in spite of the added restrictions and peddles it in little packets, adulterated, and at a fabulous price for such cheap stuff. The habit is spreading like wildfire. It is a fertile means of recruiting the inmates in the vice-trust hotels. A veritable epidemic it is, too. Cocaine is one of the most harmful of all habit-forming drugs. It used to be a habit of the underworld, but now it is creeping up, and gradually and surely reaching the higher strata of society. One thing that causes its spread is the ease with which it can be taken. It requires no smoking-dens, no syringe, no paraphernalia—only the drug itself."

Another singer had taken the place of the dancers. Kennedy leaned over and whispered to the dip.

"Say, do you and your gun-moll want to pick up a piece of change to get that mouthpiece I heard you talking about?"

The pickpocket looked at Craig suspiciously.

"Oh, don't worry; I'm all right," laughed Craig. "You see that fellow, Coke Brodie? I want to get something on him. If you will frame that sucker to get away with a whole front, there's a fifty in it."

The dip looked, rather than spoke, his amazement. Apparently Kennedy satisfied his suspicions.

"I'm on," he said quickly. "When he goes, I'll follow him. You keep behind us, and we'll deliver the goods."

"What's it all about?" I whispered.

"Why," he answered, "I want to get Brodie, only I don't want to figure in the thing so that he will know me or suspect anything but a plain hold-up. They will get him; take everything he has. There must be something on that man that will help us."

Several performers had done their turns, and the supply of the drug seemed to have been exhausted. Brodie rose and, with a nod to Loraine, went out, unsteadily, now that the effect of the cocaine had worn off. One wondered how this shuffling person could ever have carried through the wild dance. It was not Brodie who danced. It was the drug.

The dip slipped out after him, followed by the woman. We rose and followed also. Across the city Brodie slouched his way, with an evident purpose, it seemed, of replenishing his supply and continuing his round of peddling the stuff.

He stopped under the brow of a thickly populated tenement row on the upper East Side, as though this was his destination. There he stood at the gate that led down to a cellar, looking up and down as if wondering whether he was observed. We had slunk into a doorway.

A woman coming down the street, swinging a chatelaine, walked close to him, spoke, and for a moment they talked.

"It's the gun-moll," remarked Kennedy. "She's getting Brodie off his guard. This must be the root of that grapevine system, as they call it."

Suddenly from the shadow of the next house a stealthy figure sprang out on Brodie. It was our dip, a dip no longer but a regular stick-up man, with a gun jammed into the face of his victim and a broad hand over his mouth. Skilfully the woman went through Brodie's pockets, her nimble fingers missing not a thing.

"Now—beat it," we heard the dip whisper hoarsely, "and if you raise a holler, we'll get you right, next time."

Brodie fled as fast as his weakened nerves would permit his shaky limbs to move. As he disappeared, the dip sent something dark hurtling over the roof of the house across the street and hurried toward us.

"What was that?" I asked.

"I think it was the pistol on the end of a stout cord. That is a favourite trick of the gunmen after a job. It destroys at least a part of the evidence. You can't throw a gun very far alone, you know. But with it at the end of a string you can lift it up over the roof of a tenement. If Brodie squeals to a copper and these people are caught, they can't hold them under the pistol law, anyhow."

The dip had caught sight of us, with his ferret eyes in the doorway. Quickly Kennedy passed over the money in return for the motley array of objects taken from Brodie. The dip and his gun-moll disappeared into the darkness as quickly as they had emerged.

There was a curious assortment—the paraphernalia of a drug fiend, old letters, a key, and several other useless articles. The pickpocket had retained the money from the sale of the dope as his own particular honorarium.

"Brodie has led us up to the source of his supply," remarked Kennedy, thoughtfully regarding the stuff. "And the dip has given us the key to it. Are you game to go in?"

A glance up and down the street showed it still deserted. We wormed our way in the shadow to the cellar before which Brodie had stood. The outside door was open. We entered, and Craig stealthily struck a match, shading it in his hands.

At one end we were confronted by a little door of mystery, barred with iron and held by an innocent enough looking padlock. It was this lock, evidently, to which the key fitted, opening the way into the subterranean vault of brick and stone.

Kennedy opened it and pushed back the door. There was a little square compartment, dark as pitch and delightfully cool and damp. He lighted a match, then hastily blew it out and switched on an electric bulb which it disclosed.

"Can't afford risks like that here," he exclaimed, carefully disposing of the match, as our eyes became accustomed to the light.

On every side were pieces of gas-pipe, boxes, and paper, and on shelves were jars of various materials. There was a work-table littered with tools, pieces of wire, boxes, and scraps of metal.

"My word!" exclaimed Kennedy, as he surveyed the curious scene before us, "this is a regular bomb factory—one of the most amazing exhibits that the history of crime has ever produced."