"By a process of reasoning beautiful in its simplicity. The girl was seen near Craven's house. Craven knows Mannion and had a conversation with him the day of the murder. Craven will neither tell what that conversation had reference to, nor what his relationship with Mannion is. It is not a criminal relationship. I assured myself of that when I talked with Craven yesterday. The advent of the girl near Craven's house, her acquaintance with Mannion suggest a story which is probably true. She lives at Craven's because she is Craven's daughter, and both she and Craven are interested in Mannion, because she is Mannion's wife." "You've hit it," said Chick, with admiration in his eyes. "If she is Mannion's wife," remarked Patsy, "he caught a Tartar when he married her. But maybe she is only his sweetheart." "No," said Nick, "for that relation would not explain Craven's conduct. Craven might consent to shield a villainous son-in-law, but he would take the opposite course if there were only an engagement to be married. I think I'll make another trip to the Craven establishment. I have a desire to see the girl as well as to have a second talk with Craven." The detective looked at his watch. It was five o'clock. "I'll start now," he announced, "and have dinner after my return. Chick, you and Patsy may as well come along. Not to go inside the house with me, but to stay outside on watch. The girl may take a notion to run out to Mannion's hiding-place. If she does, Chick, you will follow her." Prosper Craven, pale, yet composed, opened the door of his house in response to Nick Carter's knock. "I have been expecting you," he said, when the detective had entered the living-room and had taken a seat. "I knew you would not be satisfied until you had learned what my attorney had advised." "You have seen him, then?" said Nick. "No, I have not seen him. I came to the conclusion, after you left yesterday, that I would hide nothing from you. I think the telling of the truth may be the best thing for my daughter, after all." "Your daughter is Mannion's wife, is she not?" Craven, showing surprise at this question, quietly answered: "Yes, she is married to that scoundrel." "When did the marriage take place?" "In San Francisco, two months ago. My daughter was then on a visit to her aunt. She and Mannion met at a Mission Club dance one night and took a shine to each other. Perhaps the discovery that they were both natives of Washington may have hastened the intimacy." "Did she accompany her husband to this city?" "No, she came as far as St. Louis with him. He had some business to transact in that city, he said, which would occupy his time for a few weeks. It was at his suggestion that she made the remainder of the journey alone. Now I am ready to answer any question which you may desire to ask." "Very well. To begin, what was your business with Mannion on the day of the murder?" "He wanted me to take a message to a friend of his, a Russian."