“There’s nothing much to say about what I did in the house. I spent the time after Martin had left me in carefully thinking over the remaining steps in my plan, while I unloaded and thoroughly cleaned the revolver using my handkerchief and a penholder from the desk. I also placed the packets of notes, the notecase, and the diamonds in the roll-top desk, which I opened and relocked with Manderson’s key. When I went upstairs it was a trying moment, for though I was safe from the eyes of Martin, as he sat in his pantry, there was a faint possibility of somebody being about on the bedroom floor. I had sometimes found the French maid wandering about there when the other servants were in bed. Bunner, I knew, was a deep sleeper. Mrs. Manderson, I had gathered from things I had heard her say, was usually asleep by eleven; I had thought it possible that her gift of sleep had helped her to retain all her beauty and vitality in spite of a marriage which we all knew was an unhappy one. Still it was uneasy work mounting the stairs, and holding myself ready to retreat to the library again at the least sound from above. But nothing happened.
“The first thing I did on reaching the corridor was to enter my room and put the revolver and cartridges back in the case. Then I turned off the light and went quietly into Manderson’s room.
“What I had to do there you know. I had to take off the shoes and put them outside the door, leave Manderson’s jacket, waistcoat, trousers, and black tie, after taking everything out of the pockets, select a suit and tie and shoes for the body, and place the dental plate in the bowl, which I moved from the washing-stand to the bedside, leaving those ruinous fingermarks as I did so. The marks on the drawer must have been made when I shut it after taking out the tie. Then I had to lie down in the bed and tumble it. You know all about it—all except my state of mind, which you couldn’t imagine and I couldn’t describe.
“The worst came when I had hardly begun my operations: the moment when Mrs. Manderson spoke from the room where I supposed her asleep. I was prepared for it happening; it was a possibility; but I nearly lost my nerve all the same. However. …
“By the way, I may tell you this: in the extremely unlikely contingency of Mrs. Manderson remaining awake, and so putting out of the question my escape by way of her window, I had planned simply to remain where I was a few hours, and then, not speaking to her, to leave the house quickly and quietly by the ordinary way. Martin would have been in bed by that time. I might have been heard to leave, but not seen. I should have done just as I had planned with the body, and then made the best time I could in the car to Southampton. The difference would have been that I couldn’t have furnished an unquestionable alibi by turning up at the hotel at 6:30. I should have made the best of it by driving straight to the docks, and making my ostentatious enquiries there. I could in any case have got there long before the boat left at noon. I couldn’t see that anybody could suspect me of the supposed murder in any case; but if anyone had, and if I hadn’t arrived until ten o’clock, say, I shouldn’t have been able to answer, ‘It is impossible for me to have got to Southampton so soon after shooting him.’ I should simply have had to say I was delayed by a breakdown after leaving Manderson at half-past ten, and challenged anyone to produce any fact connecting me with the crime. They couldn’t have done it. The pistol, left openly in my room, might have been used by anybody, even if it could be proved that that particular pistol was used. Nobody could reasonably connect me with the shooting so long as it was believed that it was Manderson who had returned to the house. The suspicion could not, I was confident, enter anyone’s mind. All the same, I wanted to introduce the element of absolute physical impossibility; I knew I should feel ten times as safe with that. So when I knew from the sound of her breathing that Mrs. Manderson was asleep again, I walked quickly across her room in my stocking feet, and was on the grass with my bundle in ten seconds. I don’t think I made the least noise. The curtain before the window was of soft, thick stuff and didn’t rustle, and when I pushed the glass doors further open there was not a sound.”
“Tell me,” said Trent, as the other stopped to light a new cigarette, “why you took the risk of going through Mrs. Manderson’s room to escape from the house. I could see when I looked into the thing on the spot why it had to be on that side of the house; there was a danger of being seen by Martin, or by some servant
