I did not like the jaunty bravado of the masseur which now seemed to be returning, since nothing definite had taken shape. I determined that he should not pump me, as he evidently was trying to do. I had at least fulfilled Kennedy’s commission and felt that the sooner I left Josephson the better for both of us.
I was surprised at dinner to receive a wire from Craig saying that he was bringing down Dr. Gunther, Mrs. Pearcy and Isabel to New York and asking me to have Warner Pearcy and Josephson at the laboratory at nine o’clock.
By strategy I managed to persuade Pearcy to come, and as for Josephson, he could not very well escape, though I saw that as long as nothing more had happened, he was more interested in “fixing” the police so that he could resume business than anything else.
As we entered the laboratory that night, Kennedy, who had left his party at a downtown hotel to freshen up, met us each at the door. Instead of conducting us in front of his laboratory table, which was the natural way, he led us singly around through the narrow space back of it.
I recall that as I followed him, I half imagined that the floor gave way just a bit, and there flashed over me, by a queer association of ideas, the recollection of having visited an amusement park not long before where merely stepping on an innocent-looking section of the flooring had resulted in a tremendous knocking and banging beneath, much to the delight of the lovers of slap-stick humor. This was serious business, however, and I quickly banished the frivolous thought from my mind.
“The discovery of poison, and its identification,” began Craig at last when we had all arrived and were seated about him, “often involves not only the use of chemistry but also a knowledge of the chemical effect of the poison on the body, and the gross as well as microscopic changes which it produces in various tissues and organs—changes, some due to mere contact, others to the actual chemicophysiological reaction between the poison and the body.”
His hand was resting on the poles of a large battery, as he proceeded: “Every day the medical detective plays a more and more important part in the detection of crime, and I might say that, except in the case of crime complicated by a lunacy plea, his work has earned the respect of the courts and of detectives, while in the case of insanity the discredit is the fault rather of the law itself. The ways in which the doctor can be of use in untangling the facts in many forms of crime have become so numerous that the profession of medical detective may almost be called a specialty.”
Kennedy repeated what he had already told me about electrolysis, then placed between the poles of the battery a large piece of raw beef.
He covered the negative electrode with blotting paper and soaked it in a beaker near at hand.
“This solution,” he explained, “is composed of potassium iodide. In this other beaker I have a mixture of ordinary starch.”