"Then obviously you must keep your mouth shut," said Quarles. "The fact is, Wigan, last night has got on my nerves. I am--I may as well be quite honest--I am a little afraid of going about alone. I want you to call for me and go with me." "Of course I will. But surely, with your nerves on edge, it would be wiser to keep away from psychological problems. What is the particular problem?" "Randall will explain to-night, and you must at least pretend to be interested. As regards my nerves, I can assure you this kind of thing is a relief after the other. I do not think I am a coward as a rule, but I am afraid of this unknown scoundrel. I have a presentiment that I am in very real danger." "You probably exaggerate it," I said. "Maybe. But I never ignore a strong presentiment, and I--I slept with a loaded revolver under my pillow last night, Wigan." There was no doubt as to his nervous condition; he showed it in his restlessness, in his acute consciousness of sounds in the house and in the street. He expected to be brought suddenly face to face with danger, and was afraid he would not be ready to meet it. He certainly was not himself. Zena had gone to stay with friends in the country for a few days, or I should have got her to persuade the old man to give up this psychological business--at least until he was in a normal condition again. The restaurant, where we found Dr. Randall waiting for us, was one of those excellent little French places which cannot be beaten until they have become too successful and popular, when they almost invariably deteriorate. Randall said he was delighted the professor had brought me, and dinner was served at once at a cozy table in a corner. "A patient of mine originally brought me here," said the doctor. "It is rather a discovery, I think, and personally I prefer dining where I am unlikely to come in contact with a lot of people I know. In recent years we have improved, of course; but in England we still eat, while in France they dine. Here we are practically in France." Certainly more French was spoken than English, and the doctor spoke in French to the waiter. Quarles's nervousness, which had been apparent during the drive from Chelsea, disappeared as dinner progressed, and I did not suppose a stranger like Randall would notice it. He would probably form rather a wrong impression of the professor, would look upon him as a highly-strung man, and would not realize that he was not in a normal condition this evening. Randall carried his profession in his face, but for the time being his medical manner was laid aside; nor did he speak of the business which had brought us together until we had got to the coffee and liqueur stage. "I suppose you read the papers I sent you, Professor?" "Yes, but rather cursorily," Quarles answered. "I think if you told the whole story I should understand it better; besides, my friend here knows nothing of it, and will bring an unbiased mind to bear upon it."