Colwyn was upstairs in his bedroom preparing for his return journey to London when a meek knock and an apologetic cough reached his ears. He turned and saw Tufnell standing at the half-open door. The face of the old butler wore a look of mingled determination and nervousness--the expression of a timid man who had braced himself to a bold course of action after much irresolute deliberation. "I beg your pardon, sir," he said, and his trepidation was apparent in his voice. "But might I--that is to say, could you spare me a few minutes' conversation?" "Certainly," replied the detective. "Come inside, Tufnell. What is it?" The butler entered the room and carefully closed the door behind him. "I am sorry to interrupt you, sir," he said. "But I have just heard Miss Heredith give orders for your car to be got ready for your return to London, and I knew there was no time to be lost. It's about the--the murder, sir." He brought out the last words with an effort. "Go on," said Colwyn, wondering what further surprise was in store for him. "It's about something that happened on that night. I wanted to tell you before, but I didn't like to. After the murder was discovered I was sent over to the village to fetch the police and the doctor, and while I was hurrying through the woods near the moat-house I thought I saw a man crouching behind one of the trees near the carriage drive. He seemed to be looking towards me. When I looked again he was gone." "And what did you do?" "I called out, but received no answer, so I hurried on." Colwyn scrutinized the butler with a thoughtful penetrating glance. The butler bore the look with the meek air of a domestic animal who knows that he is being appraised. "Am I the first person to whom you have told this story?" the detective asked after a pause. "Yes, sir." "Why did you not inform the police officers when they were investigating the case?" "For several reasons, sir. It seemed to me, when I came to think it over, that it must have been my fancy, and then it passed out of my mind in the worry and excitement of the house. Then, when I did think of it again, I didn't like to mention it to Superintendent Merrington, because he was such a bullying sort of gentleman that I felt quite nervous of him. Really, for a gentleman who has travelled with Royal Highnesses, as I've heard tell, and might be supposed to know how gentlemen behave, the way he treated the servants while he was here was almost too much for flesh and blood to bear." The butler's withered cheeks flushed faintly at the recollection. "I couldn't bring myself to tell him, sir." Colwyn smiled slightly. He was not unacquainted with Merrington's methods of cross-examination. "You could have spoken to Detective Caldew, the other officer engaged in the case," he said. "Young Tom Caldew!" exclaimed the butler, in manifest surprise. "You know him then?"