Catching a glimpse of us, he beat a retreat across the opposite end of the room, beckoning to the proprietor, who joined him outside the door.  I thought I heard him ask:  “Who are those men?  Who let them in?” but I could not catch the reply.

One by one the other occupants of the room rose and sidled out, leaving us alone with the Gay Cat.  Kennedy reached over to get a cigarette from my case and light it from one that I was smoking.

“That’s our man, I think,” he whispered—­“Pitts Slim.”

I said nothing, but I would have been willing to part with a large section of my bank-account to be up on the Chatham Square station of the Elevated just then.

There was a rush from the half-open door behind us.  Suddenly everything turned black before me; my eyes swam; I felt a stinging sensation on my head and a weak feeling about the stomach; I sank half-conscious to the floor.  All was blank, but, dimly, I seemed to be dragged and dropped down hard.

How long I lay there I don’t know.  Kennedy says it was not over five minutes.  It may have been so, but to me it seemed an age.  When I opened my eyes I was lying on my back on a very dirty sofa in another room.  Kennedy was bending over me with blood streaming from a long deep gash on his head.  Another figure was groaning in the semi-darkness opposite; it was the Gay Cat.

“They blackjacked us,” whispered Kennedy to me as I staggered to my feet.  “Then they dragged us through a secret passage into another house.  How do you feel?”

“All right,” I answered, bracing myself against a chair, for I was weak from the loss of blood, and dizzy.  I was sore in every joint and muscle.  I looked about, only half comprehending.  Then my recollection flooded back with a rush.  We had been locked in another room after the attack, and left to be dealt with later.  I felt in my pocket.  I had left my watch at the laboratory, but even the dollar watch I had taken and the small sum of money in my pocketbook were gone.

Kennedy still had his camera slung over his shoulder, where he had fastened it securely.

Here we were, imprisoned, while Pitts Slim, the man we had come after, whoever he was, was making his escape.  Somewhere across the street was O’Connor, waiting in a room as we had agreed.  There was only one window in our room, and it opened on a miserable little dumbwaiter air-shaft.  It would be hours yet before his suspicions would be aroused and he would discover which of the houses we were held in.  Meanwhile what might not happen to us?

Kennedy calmly set up his tripod.  One leg had been broken in the rough-house, but he tied it together with his handkerchief, now wet with blood.  I wondered how he could think of taking a picture.  His very deliberation set me fretting and fuming, and I swore at him under my breath.  Still, he worked calmly ahead.  I saw him take the black box and set it on the tripod.  It was indistinct in the darkness.  It looked like a camera, and yet it had some attachment at the side that was queer, including a little lamp.  Craig bent and attached some wires about the box.