"I have it," exclaimed Garrick, as we were retracing our steps upstairs from the dank darkness of the cellar. "I would be willing to wager that that tunnel runs back from this house to that pool-room for women which we visited on Forty-seventh Street, Marshall. That must be the secret exit. Don't you see, it could be used in either direction."

We climbed the stairs and stood again in the wreck of things, taking a hasty inventory of what was left, in hope of uncovering some new clew, even by chance.

Garrick shook his head mournfully.

"They had just time enough," he remarked, "to destroy about everything they wanted to and carry off the rest."

"All except the markers," I corrected.

"That was just a lucky chance," he returned. "Still, it throws an interesting sidelight on the case."

"It doesn't add much in my estimation to the character of Forbes," I ventured, voicing my own suspicions.

The telephone bell rang before Garrick had a chance to reply. Evidently in their haste they had not had time to cut the wires or to spread the news, yet, of the raid. Someone who knew nothing of what had happened was calling up.

Garrick quickly unhooked the receiver, with a hasty motion to us to remain silent.

"Hello," we heard him answer. "Yes, this is it. Who is this?"

He had disguised his voice. We waited anxiously and watched his face to gather what response he received.

"The deuce!" he exclaimed, with his hand over the transmitter so that his voice would not be heard at the other end.

"What's the matter?" I asked eagerly.

"Whoever he was," replied Garrick, "he was too keen for me. He caught on. There must have been some password or form that they used which we don't know, for he hung up the receiver almost as soon as he heard me."

Garrick waited a minute or two. Then he whistled into, the transmitter. It was done apparently to see whether there was anyone listening. But there was no answer. The man was gone.

"Operator, operator!" Guy was calling, insistently moving the hook up and down rapidly. "Yes—I want Central. Central, can you tell me what number that was which just called up?"

We all waited anxiously to learn whether the girl could find out or not.

"Bleecker seven—one—eight—o? Thank you very much. Give me information, please."

Again we waited as Garrick tried to trace the call out.

"Hello! What is the street address of Bleecker seven—one—eight—o?
Three hundred West Sixth. Thank you. A garage? Good-bye."

"A garage?" echoed Dillon, his ears almost going up as he realized the importance of the news.

"Yes," cried Garrick, himself excited. "Tom, call a cab. Let us hustle down there as quickly as we can."

"One of those garages on the lower West Side," I heard Dillon say as I left. "Perhaps they did work for the gambling joint—sent drunks home, got rid of tough customers and all that. You know already that there are some pretty tough places down there. This is bully. I shouldn't be surprised if it gave us a line on the stealing of Warrington's car at last."

I found a cab and Dillon and Garrick joined me in it.

"I tried to get McBirney," said Garrick as we prepared to start on our new quest, "but he was out, and the night operator at his place didn't seem to know where he was. But if they can locate him, I imagine he'll be around at least shortly after we get there. I left the address."

Dillon had issued his final orders to his raiders about guarding the raided gambling joint and stationing a man at the door. A moment later we were off, threading our way through the crowd which in spite of the late hour still lingered to gape at the place.

On the way down we speculated much on the possibility that we might be going on a wild goose chase. But the very circumstances of the call and the promptness with which the man who had called had seemed to sense when something was wrong and to ring off seemed to point to the fact that we had uncovered a good lead of some kind.

After a quick run downtown through the deserted avenues, we entered a series of narrow and sinuous streets that wound through some pretty tough looking neighborhoods. On the street corners were saloons that deserved no better name than common groggeries. They were all vicious looking joints and uniformly seemed to violate the law about closing. The fact was that they impressed one as though it would be as much as one's life was worth even to enter them with respectable looking clothes on.

The further we proceeded into the tortuous twists of streets that stamp the old Greenwich village with a character all its own, the worse it seemed to get. Decrepit relics of every style of architecture from almost the earliest times in the city stood out in the darkness, like so many ghosts.

"Anyone who would run a garage down here," remarked Garrick, "deserves to be arrested on sight."

"Except possibly for commercial vehicles," I ventured, looking at the warehouses here and there.

"There are no commercial vehicles out at this hour," added Garrick dryly.

At last our cab turned down a street that was particularly dark.

"This is it," announced Garrick, tapping on the glass for the driver to stop at the corner. "We had better get out and walk the rest of the way."

The garage which we sought proved to be nothing but an old brick stable. It was of such a character that even charity could not have said that it had seen much better days for generations. It was dark, evil looking. Except for a slinking figure here and there in the distance the street about us was deserted. Even our footfalls echoed and Garrick warned us to tread softly. I longed for the big stick, that went with the other half of the phrase.

He paused a moment to observe the place. It was near the corner and a dim-lighted Raines law saloon on the next cross street ran back almost squarely to the stable walls, leaving a narrow yard. Apparently the garage itself had been closed for the night, if, indeed, it was ever regularly open. Anyone who wanted to use it must have carried a key, I surmised.

We crossed over stealthily. Garrick put his ear to an ordinary sized door which had been cut out of the big double swinging doors of the stable, and listened.

Not a sound.

Dillon, with the instinct of the roundsman in him still, tried the handle of the door gently. To our surprise it moved. I could not believe that anyone could have gone away and left it open, trusting that the place would not be looted by the neighbours before he returned. I felt instinctively that there must be somebody there, in spite of the darkness.

The commissioner pushed in, however, followed closely by both of us, prepared for an on-rush or a hand-to-hand struggle with anything, man or beast.

A quick succession of shots greeted us. I do not recall feeling the slightest sensation of pain, but with a sickening dizziness in the head I can just vaguely remember that I sank down on the oil and grease of the floor. I did not fall. It seemed as if I had time to catch myself and save, perhaps, a fractured skull. But then it was all blank.

It seemed an age, though it could not have been more than ten minutes later when I came to. I felt an awful, choking sensation in my throat which was dry and parched. My lungs seemed to rasp my very ribs, as I struggled for breath. Garrick was bending anxiously over me, himself pale and gasping yet. The air was reeking with a smell that I did not understand.

"Thank heaven, you're all right," he exclaimed, with much relief, as he helped me struggle up on my feet. My head was still in a whirl as he assisted me over to a cushioned seat in one of the automobiles standing there. "Now I'll go back to Dillon," he added, out of breath from the superhuman efforts he was putting forth both for us and to keep himself together. "Wh—what's the matter? What happened?" I gasped, gripping the back of the cushion to steady myself. "Am I wounded? Where was I hit? I—I don't feel anything—but, oh, my head and throat!"

I glanced over at Dillon. He was pale and white as a ghost, but I could see that he was breathing, though with difficulty. In the glare of the headlight of a car which Garrick had turned on him, he looked ghastly. I looked again to discover traces of blood. But there was none anywhere.

"We were all put out of business," muttered Garrick, as he worked over
Dillon. Dillon opened his eyes blankly at last, then struggled up to
his feet. "You got it worst, commissioner," remarked Garrick to him.
"You were closest."

"Got what?" he sputtered, "Was closest to what?"

We were all still choking over the peculiar odor in the fetid air about us.

"The bulletless gun," replied Garrick.

Dillon looked at him a moment incredulously, in spite even of his trying physical condition.

"It is a German invention," Garrick went on to explain, clearing his throat, "and shoots, instead of bullets, a stupefying gas which temporarily blinds and chokes its victims. The fellow who was in here didn't shoot bullets at us. He evidently didn't care about adding any more crimes to his list just now. Perhaps he thought that if he killed any of us there would be too much of a row. I'm glad it was as it was, anyway. He got us all, this way, before we knew it. Perhaps that was the reason he used the gun, for if he had shot one of us with a pistol I had my own automatic ready myself to blaze away. This way he got me, too.

"A stupefying gun!" repeated Dillon. "I should say so. I don't know what happened—yet," he added, blinking.

"I came to first," went on Garrick, now busily looking about, as we were all recovered. "I found that none of us was wounded, and so I guessed what had happened. However, while we were unconscious the villain, whoever he was, succeeded in running his car out of the garage and getting away. He locked the door after him, but I have managed to work it open again."

Garrick was now examining the floor of the garage, turning the headlight of the machine as much as he could on successive parts of the floor.

"By George, Tom," he exclaimed to me suddenly, "see those marks in the grease? Do you recognize them by this time? It is the same tire-mark again—Warrington's car—without a doubt!"

Dillon had taken the photographs which Garrick had made several days before from the prints left by the side of the road in New Jersey, and was comparing them himself with the marks on the floor of the garage, while Garrick explained them to him hurriedly, as he had already done to me.

"We are getting closer to him, every time,'" remarked Garrick. "Even if he did get away, we are on the trail and know that it is the right one. He could not have been at the gambling joint, or he would never have called up. Yet he must have known all about it. This has turned out better than I expected. I suppose you don't feel so, but you must think so."

It was difficult not to catch the contagion of Garrick's enthusiasm.
Dillon grunted assent.

"This garage," he put in, looking it over critically, "must act as a fence for stolen cars and parts of cars. See, there over in the corner is the stuff for painting new license numbers. Here's enough material to rebuild a half dozen cars. Yes, this is one of the places that ought to interest you and McBirney, Garrick. I'll bet the fellow who owns this place is one of those who'd engage to sell you a second-hand car of any make you wanted to name. Then he'd go out on the street and hunt around until he got one. Of course, we'll find out his name, but I'll wager that when we get the nominal owner we won't be able to extract a thing from him in the way of actual facts."

Garrick had continued his examination of the floor. In a corner, near the back, he had picked up an empty shell of a cartridge. He held it down in the light of the car, and examined it long and carefully. As he turned it over and over he seemed to be carefully considering it. Finally, he dropped it carefully into his inside vest pocket, as though it were a rare treasure.

"As I said at the start," quoted Garrick, turning to me, "we might get a conviction merely on these cartridges. Anyhow, our man has escaped from here. You can be sure that he won't come back—perhaps never—certainly not at least for a long time, until he figures that this thing has completely blown over."

"I'm going to keep my eye on the place, just the same," stoutly insisted Dillon.

"Of course, by all means," reiterated Garrick. "The fact is, I expect our next important clew will come from this place. The only thing I want you to be careful of, Dillon, is not to be hasty and make an arrest."

"Not make an arrest?" queried Dillon, who still felt the fumes in his throat, and evidently longed to make someone pay the price—at least by giving him the satisfaction of conducting a "third degree" down at headquarters.

"No. You won't get the right man, and you may lose one who points straight at him. Take my advice. Watch the place. There's more to be gained by going at it cautiously. These people understand the old hammer-and-tongs game."

Just then the smaller outside door grated on its rusty hinges. We sprang to our feet, startled. Dillon leaped forward. Stupefying guns had no taming effect on his nationality.

"Well, commish, is that the way you greet an old friend?" laughed McBirney, as a threatened strangle-hold was narrowly averted and turned into a handshake. "How are you fellows? I got your message, Garrick, and thought I'd drop around. What's the matter? You all look as if you'd been drawn through a wringer."

Briefly, to the accompaniment of many expressions of astonishment from the insurance detective, Garrick related what had happened, from the raid to the gas-gun.

"Well," gasped McBirney, sniffing the remains of the gas in the air, "this is some place, isn't it? Neat, cozy, well-located—for a murder—hello!—that's that ninety horsepower Despard that was stolen from Murdock the other day, or I'll eat my hat."

He had raised the hood and was straining his eyes to catch a glimpse of the maker's number on the engine, which had been all but obliterated by a few judicious blows of a hammer.

Garrick was busy telling McBirney also about the marks of the tire on the floor, as the detective looked over one car after another, as if he had unearthed a veritable treasure-trove.

"No, your man could not have been at either of the gambling joints," agreed McBirney, as Garrick finished, "or he wouldn't have called up. But he must have known them intimately. Perhaps he was in the pay of someone there."

McBirney was much interested in what had been discovered, and was trying to piece it together with what we had known before. "I wonder whether he's the short fellow who drove the car when it was seen up there, or the big fellow who was in the car when Warrington was shot, up-state?"

The question was, as yet, unanswerable. None of us had been able to catch a glimpse of his figure, muffled, in the darkness when he shot us.

All we knew was that even this man was unidentified and at large. The murderer, desperate as he was, was still free and unknown, too. Were they one and the same? What might not either one do next?

We sat down in one of the stolen cars and held a midnight council of war. There were four of us, and that meant four different plans. Dillon was for immediate and wholesale arrests. McBirney was certain of one thing. He would claim the cars he could identify. The garage people could not help knowing now that we had been there, and we conceded the point to him with little argument, though it took great tact on Garrick's part to swing over Dillon.

"I'm for arresting the garage-keeper, whoever he proves to be," persisted Dillon, however.

"It won't do any good," objected Garrick.

"Don't you see that it will be better to accept his story, or rather seem to, and then watch him?"

"Watch him?" I asked, eager to propose my own plan of waiting there and seizing each person who presented himself. "How can you watch one of these fellows? They are as slippery as eels,—and as silent as a muffler," I added, taking good-humouredly the general laugh that greeted my mixed metaphor.

"You've suggested the precise idea, Marshall, by your very objection," broke in Garrick, who up to this time had been silent as to his own plan.

"I've a brand-new system of espionage. Trust it to me, and you can all have your way."