I was thoroughly tired, though not so much so that my dreams were not haunted by a succession of baleful eyes peering at me from the darkness.

I slept late, but was awakened by a knocking on the door.  As I rose to answer it I saw through the open door of Kennedy’s room that he had been about early and must already be at the laboratory.  How he did it I don’t know.  My own newspaper experience had made me considerable of a nighthawk.  But I always paid for it by sleeping the next day.  With Kennedy, when he was on a case, even five hours of sleep was more than he seemed able to stand.

“Hello, Jameson,” greeted a voice, as I opened the door.  “Is Kennedy in—­oh, he hasn’t come back yet?”

It was Lockwood, at first eager to see Craig, then naturally crestfallen because he saw that he was not there.

“Yes,” I replied, rubbing my eyes.  “He must be at the laboratory.  If you’ll wait a minute while I slip on my clothes, I’ll walk over there with you.”

While I completed my hasty toilet, Lockwood sat in our living room, gazing about with fascination at the collection of trophies of the chase of criminals.

“This is positively a terrifying array of material, Jameson,” he declared, as at last I emerged.  “Between what Kennedy has here and what he has stowed away in that laboratory of his, I wonder that any one dares be a crook.”

I could not help eying him keenly.  Could he have spoken so heartily if he had known what it was, damning to himself, that Kennedy had tucked away in the laboratory?  If he knew, he must have been a splendid actor, one of those whom only the minute blood-pressure test of the sphygmograph could induce to give up a secret, and then only in spite of himself.

“It is wonderful,” I agreed.  “Are you ready?”

We left the apartment and walked along in the bracing morning air toward the campus and the Chemistry Building.  Sure enough, as I had expected, Kennedy was in his laboratory.

As we entered he was verifying his experiments and checking over his results, carefully endeavouring to isolate any of the other closely related mydriatic alkaloids that might be contained in the noxious fumes of the poisoned tobacco.

Though Craig was already convinced of what was going on, I knew that he always considered it a matter of considerable medico-legal importance to be exact, for if the affair ever came to the stage of securing an indictment the charge could be sustained only by specific proof.

As we appeared in the door, however, he laid aside his work, and greeted us.

“I suppose Jameson has already told you that I called you up last night—­and what I said?” began Lockwood.

Kennedy nodded.  “It was something about Norton, wasn’t it?”

Lockwood leaned over impressively and almost whispered:  “Of course, you are in no position to know, but there are ugly rumours current down in Lima among the natives regarding that dagger.”