At three o’clock the waiting room of the office was full, and a long line of men extended down the stairs. The crowd bore striking witness to the horde of unemployed seeking for even the slightest chance of employment. My friend’s clerks were in despair, but somehow they managed to evolve something like order from the mass, and one by one the applicants were admitted. After the first half dozen, we saw that they could be divided into three classes,--the men who knew nothing about science and nothing about any kind of ink, the men who knew something about ink but nothing about phosphorescent ink, and the men who had been laboratory assistants to various research followers. We divided them rapidly on this basis, and in an hour had dismissed all the members of classes one and two. There were left some ten others who had been assistants in research laboratories. One by one we examined these. They had worked in various lines; the first five in chemical researches; the last five in various physical and engineering lines. Try as we might, we could get no information from any of them with regard to phosphorescent ink, or with regard to any unusual work with radio-active energy. The last man had been dismissed and we had sat down to afternoon tea with my friend, when we heard words in the outer office. The door opened and a clerk entered. “There’s one man more, sir,” he said, “I told him he was too late, but he’s quite insistent, sir. Will you care to see him?” “Surely,” I said, and we all went out into the outer office. A tall, bent man with drooping mustache stood by the window. His gaunt face and threadbare clothes, neatly brushed though they were, showed an evident lack of prosperity. “I ventured to insist, sir,” he said, addressing me, “as I have had quite a little experience in phosphorescent ink. It was only a year ago that I served in a laboratory where they were working with it, and while I was simply working under the direction of other people, I think I could work well along that line. I should try to do my best. I need a place.” This looked more like the real thing. I waved towards Tom. He could run this end of the inquiry better than I. “What’s your name?” “George Swenton.” “Where did you have your experience?” questioned Tom. “With Doctor Heidenmuller, in his private research laboratory,” answered the man. “What training have you had?” “Not much. Only a few courses at the University of London. I was only the second assistant. I worked with Doctor Heidenmuller for four years, until he died six months ago. I have had no place since, sir.” “Did your employer do anything with radio-active work?” “Yes, sir. He died that way. He was killed, paralysed, you might say, while working with something in a locked room. He always did that work in a locked room.” “What were the circumstances of his death?” asked Tom. The man hesitated and looked up somewhat fearfully.