"Looks pretty deserted here," remarked Garrick to Dillon\'s man, who had accompanied us from the door into the now deserted gambling den.

"Yes," he grinned, "there\'s not much use in keeping me here since they took all the stuff to headquarters. Now and then one of the old rounders who has been out of town and hasn\'t heard of the raid comes in. You should see their faces change when they catch sight of my uniform. They never stop to ask questions," he chuckled. "They just beat it."

I was wondering how the police regarded Garrick\'s part in the matter, and while Garrick was busy I asked, "Have you seen Inspector Herman lately?"

The man laughed.

"What\'s the matter?" I asked, "Is he sore at having the raid pulled off over his head?"

"Sore?" the roundsman repeated, "Oh, not a bit, not a bit. He enjoyed it. It gave him so much credit," the man added sarcastically, "especially after he fell down in getting the evidence against that other place around the corner."

"Was that his case, too?" I asked.

"Sure," replied the policeman. "Didn\'t you know that? That Rena Taylor was working under his orders when she was killed. They tell me at headquarters he\'s working overtime on the case and other things connected with it. He hasn\'t said much, but there\'s someone he is after—I know. Mark my words. Herman is always most dangerous when he\'s quiet. The other day he was in here, said there was a man who used to be seen here a good deal in the palmy days, who had disappeared. I don\'t know who he was, but Herman asked me to keep a particular lookout to see if he came back for any purpose. There\'s someone he suspects, all right."

I wondered why the man told me. He must have seen, by the look on my face, that I was thinking that.

"I wouldn\'t tell it to everybody," he added confidentially, "only, most of us don\'t like Herman any too well. He\'s always trying to hog it all—gets all the credit if we pick up a clew, and,—well, most of us wouldn\'t be exactly disappointed to see Mr. Garrick succeed—that\'s all."

Garrick was calling from the back room to me, and I excused myself, while the man went back to his post at the front door. Garrick carefully closed the door into the room.

While I had been busy getting the copies of the faked edition of the Star, which had so alarmed the owner of the garage and had set things moving rapidly, Garrick had also been busy, in another direction. He had explored not only the raided gambling den, but the little back yard which ran all the way to an extension on the rear of the house in the next street, in which was situated the woman\'s poolroom.

He had explored, also, the caved-in tunnel enough to make absolutely certain that his suspicions had been correct in the first place, and that it ran to this other joint, from which the gamblers had made their escape. That had satisfied him, however, and he had not unearthed the remains of the tunnel or taken any action in the matter yet. Something else appeared to interest him much more at the present moment.

"I found," he said when he was sure that we were alone, "that the feed wire of the arc light that burns all the time in that main room over there in the place on Forty-seventh Street—you recall it?—runs in through the back of the house."

He was examining two wires which, from his manner, I inferred were attached to this feed wire, leading to it from the room in which we now were. What the purpose of the connection was I had no idea. Perhaps, I thought, it was designed to get new evidence against the place, though I could not guess how it was to be done. So far, except for what we had seen on our one visit, there had appeared to be no real evidence against the place, except, possibly, that which had died with the unfortunate Rena Taylor.

"What\'s that?" I asked, as Garrick produced a package from a closet where he had left it, earlier in the day.

I saw, after he had unwrapped it, that it was a very powerful microphone and a couple of storage cells. He attached it to the wire leading out to the electric light feed wire.

"I had provided it to be used in an emergency," he replied. "I think the time has come sooner than I anticipated."

I watched him curiously, wondering what it would be that would come next.

There followed a most amazing series of groanings and mutterings from Garrick. I could not imagine what he was up to. The whole proceeding seemed so insane that, for the moment, it left me nonplussed and speechless.

Garrick caught the puzzled look on my face.

"What\'s the matter?" he laughed heartily, cutting out the microphone momentarily and seeming to enjoy the joke to the utmost.

"Would you prefer to be sent to a State or a private institution?" I rasped, testily. "What insanity is all this? It sounds like the fee-faw-fum and mummery of a voodoo man."

"Come, now, Tom," he rejoined, argumentatively. "You know as well as I do what sort of people those gamblers are—superstitious as the deuce. I did this once before to-day. This is a good time to do it again, before they persuade themselves that there is nothing in that story which we printed in the Star. That fellow is in there now, probably in that room where we were, and it is possible that they may reassure him and settle his fears. Now, just suppose a murder had been committed in a room, and you knew it, and heard groanings and mutterings—from nowhere, just in the air, about you, overhead—what would you do, if you were inclined to be superstitious?"

Before I could answer, he had resumed the antics which before I had found so inexplicable.

"Cut out and run, I suppose," I replied. "But what has that to do with the case? The groanings are here—not there. You haven\'t been able to get in over there to attach anything, have you? What do you mean?"

"No," he admitted, "but did you ever hear what you could do with a microphone, a rheostat, and a small transformer coil if you attached them properly to a direct-current electric lighting circuit? No? Well, an amateur with a little knowledge of electricity could do it. The thing is easily constructed, and the result is a most complicated matter."

"Well?" I queried, endeavouring to follow him.

"The electric arc," he continued, "isn\'t always just a silent electric light. You know that. You\'ve heard them make noises. Under the right conditions such a light can be made to talk—the \'speaking arc,\' as Professor Duddell calls it. In other words, an arc light can be made to act as a telephone receiver."

I could hardly believe the thing possible, but Garrick went on explaining.

"You might call it the arcophone, I suppose. The scientific fact of the matter is that the arc is sensitive to very small variations of the current. These variations may run over a wide range of frequency. That suggested to Duddell that a direct-current arc might be used as a telephone receiver. All that you need is to add a microphone current to the main arc current. The arc reproduces sounds and speech distinctly, loud enough, even, to be heard several feet away from the light."

He had cut out the microph............