"Just what I'm saying. There were two or three assistants. Pretty big doctors, I learned later, all of them from Boston. They had taken a cadaver from the refrigerator and stood it in a certain position. Then the one man had struck it on the head with the mallet with all the force he could summon. Of course it knocked the corpse down—I'm telling you, it was gruesome, even to an interne! The last I saw of them, the doctors were working with their microscopes—evidently to see what effect the blow had produced."
"What was the idea?"
"Never found out. They're pretty close-mouthed about that sort of thing. You see, opposite sides in a trial are always carrying out experiments and trying their level best to keep the other fellow from knowing what's going on. I found out later that the door was supposed to have been locked. I passed through about ten minutes later and saw them working on another human body—evidently one of a number that they had been trying the tests on. About that time some one heard me and came out like a bullet. The next thing I knew, everything was closed. How long the experiments had been going on, I couldn't say. I do know, however, that they didn't leave there until about three o'clock in the morning."
"You—you don't know who the men were?" Houston, forcing himself to be casual, had asked the question. The young doctor shook his head.
"No—except that they were from Boston. At least, the doctors were. One of the nurses knew them. I suppose the other man was a district attorney—they usually are around somewhere during an experiment."
"You never learned with what murder case it was connected?"
"No—the fact is, it passed pretty much out of my mind, as far as the details were concerned. Although I'll never forget the picture."
"Pardon me for asking questions. I—I—just happen to come from Boston and was trying to recall such a case. You don't remember what time of the year it was, or how long ago?"
"Yes, I do. It was in the summer, along about two or two and a half years ago."
Houston slumped back into his corner. Ten minutes later, he found an opportunity to exchange cards with the young physician and sought his berth. To himself, he could give no reason for establishing the identity of the smoking-compartment informant. He had acted from some sort of subconscious compulsion, without reasoning, without knowing why he had catalogued the information or of what possible use it could be to him. But once in his berth, the picture continued to rise before him; of a big room in a hospital, of doctors gathered about, and of a man "killing" another with a mallet. Had it been Worthington? Worthington, the tired-eyed, determined, over-zealous district attorney, who, day after day, had struggled and fought to send him to the penitentiary for life? Had it been Worthington, striving to reproduce the murder of Tom Langdon as he evidently had reconstructed it, experimenting with his experts in the safety of a different city, for points of evidence that would clinch the case against the accused man beyond all shadow of a doubt? Instinctively Houston felt that he just had heard an unwritten, unmentioned phase of his own murder case. Yet—if that had been Worthington, if those experts had found evidence against him, if the theories of the district attorney had been verified on that gruesome night in the "dead ward" of Bellstrand Hospital—