"What is it?" I asked, mystified.

"a.r.s.eniuretted hydrogen," he answered, still engaged in verifying his tests. "This is the Marsh test for a.r.s.enic."

I gazed from Kennedy to the apparatus, then to Rusty and a picture of Elaine, pale and listless, flashed before me.

"a.r.s.enic!" I repeated in horror.

I had scarcely recovered from the surprise of Kennedy's startling revelation when the telephone rang again. Kennedy seized the receiver, thinking evidently that the message might be from or about Elaine.

But from the look on his face and from his manner, I could gather that, although it was not from Elaine herself, it was about something that interested him greatly. As he talked, he took his little notebook and hastily jotted down something in it. Still, I could not make out what the conversation was about.

"Good!" I heard him say finally. "I shall keep the appointment--absolutely."

His face wore a peculiar puzzled look as he hung up the receiver.

"What was it?" I asked eagerly.

"It was Elaine's footman, Michael," he replied thoughtfully. "As I suspected, he says that he is a confederate of the Clutching Hand and if we will protect him he will tell us the trouble with Elaine."

I considered a moment. "How's that?" I queried.

"Well," added Craig, "you see, Michael has become infuriated by the treatment he received from the Clutching Hand. I believe he cuffed him in the face yesterday. Anyway, he says he has determined to get even and betray him. So, after hearing how Elaine was, he slipped out of the servant's door and looking about carefully to see that he wasn't followed, he went straight to a drug store and called me up. He seemed extremely nervous and fearful."

I did not like the looks of the thing, and said so. "Craig," I objected vehemently, "don't go to meet him. It is a trap."

Kennedy had evidently considered my objection already.

"It may be a trap," he replied slowly, "but Elaine is dying and we've got to see this thing through."

As he spoke, he took an automatic from a drawer of a cabinet and thrust it into his pocket. Then he went to another drawer and took out several sections of thin tubing which seemed to be made to fasten together as a fishing pole is fastened, but were now separate, as if ready for travelling.

"Well--are you coming, Walter?" he asked finally--the only answer to my flood of caution.

Then he went out. I followed, still arguing.

"If YOU go, _I_ go," I capitulated. "That's all there is to it."

Following the directions that Michael had given over the telephone Craig led me into one of the toughest parts of the lower West Side.

"Here's the place," he announced, stopping across the street from a dingy Raines Law Hotel.

"Pretty tough," I objected. "Are you sure?"

"Quite," replied Kennedy, consulting his note book again.

"Well, I'll be hanged if I'll go in that joint," I persisted.

It had no effect on Kennedy. "Nonsense, Walter," he replied, crossing the street.

Reluctantly I followed and we entered the place.

"I want a room," asked Craig as we were accosted by the proprietor, comfortably clad in a loud checked suit and striped shirt sleeves. "I had one here once before--forty-nine, I think."

"Fifty--" I began to correct.

Kennedy trod hard on my toes.

"Yes, forty-nine," he repeated.

The proprietor called a stout negro porter, waiter, and bell-hop all combined in one, who led us upstairs.

"Fohty-nine, sah," he pointed out, as Kennedy dropped a dime into his ready palm.

The negro left us and as Craig started to enter, I objected, "But, Craig, it was fifty-nine, not forty-nine. This is the wrong room."

"I know it," he replied. "I had it written in the book. But I want forty-nine--now. Just follow me, Walter."

Nervously I followed him into the room.

"Don't you understand?" he went on. "Room forty-nine is probably just the same as fifty-nine, except perhaps the pictures and furniture, only it is on the floor below."

He gazed about keenly. Then he took a few steps to the window and threw it open. As he stood there he took the parts of the rods he had been carrying and fitted them together until he had a pole some eight or ten feet long. At one end was a curious arrangement that seemed to contain lenses and a mirror. At the other end was an eye-piece, as nearly as I could make out.

"What is that?" I asked as he completed his work.

"That? That is an instrument something on the order of a miniature submarine periscope," Craig replied, still at work.

I watched him, fascinated at his resourcefulness. He stealthily thrust the mirror end of the periscope out of the window and up toward the corresponding window up stairs. Then he gazed eagerly through the eye-piece.

"Walter--look!" he exclaimed to me.

I did. There, sure enough, was Michael, pacing up and down the room. He had already preceded us. In his scared and stealthy manner, he had entered the Raines Law hotel which announced "Furnished Rooms for Gentlemen Only." There he had sought a room, fifty-nine, as he had said.

As he came into the room, he had looked about, overcome by the enormity of what he was about to do. He locked the door. Still, he had not been able to avoid gazing about fearfully, as he was doing now that we saw him.

Nothing had happened. Yet he brushed his hand over his forehead and breathed a sigh of relief. The air seemed to be stifling him and already he had gone to the window and thrown it open. Then he had gazed out as though there might be some unknown peril in the very air. He had now drawn back from the window and was considering. He was actually trembling. Should he flee? He whistled softly to himself to keep his shaking fears under control. Then he started to pace up and down the room in nervous impatience and irresolution.

As I looked at him nervously walking to and fro, I could not help admitting that things looked safe enough and all right to me. Kennedy folded the periscope up and we left our room, mounting the remaining flight of stairs.

In fifty-nine we could hear the measured step of the footman. Craig knocked. The footsteps ceased. Then the door opened slowly and I could see a cold blue automatic.

"Look out!" I cried.

Michael in his fear had drawn a gun.

"It's all right, Michael," rea.s.sured Craig calmly. "All right, Walter,"

he added to me.