“As the murderer was presumably flesh and blood and there was no hole in walls or floor, I fastened on the ‘descent’ theory, which was subsequently confirmed by an examination of the wall outside and above the open study window. Over this wall—over the whole house, in fact—the commonest and creepiest of creepers creeps. I refer to _Ampelopsis Veitchii_. A large drainage-pipe runs to earth beside the study window in question, and for a space of perhaps half a foot on each side of it throughout its length the creeper has been cleared away. But half-way between the top of the window through which the murderer entered the study and the first-floor windows above it, a shoot of creeper has pushed its way out into the cleared space beside the pipe. This shoot drew my attention because it was black and shrivelled. “_Ampelopsis Veitchii_, though one of the commonest forms of creeper, is also one of the most tender. A sharp blow upon the main branch of a shoot: means death to that shoot within a few hours. The dead piece of creeper I refer to was, I thought at first, at that point on the wall where it might have been struck by the feet of a man of middle height climbing out of either of the first-floor windows over the open one of the study at the moment when he was clutching the sill with one or both hands and hanging with arms bent. “It was, I saw, clearly impossible for the murderer to have dropped from the upper window on to the sill of the open study window and so miraculously to have retained his balance that he did not fall on to the flower-bed. Also—in spite of the novelists—there are few drain-pipes which can be used to climb by. This drain-pipe is no exception. Fingers could not be clasped round it; neither would it support more than a five or six-stone weight. It was clear, therefore, that the murderer, in descending the wall, had used something to climb down—probably a rope. (Descent of the wall was another confirmation of the theory that the murderer was of the house.) “It will have been noticed that I have used the masculine personal pronoun to describe the murderer. Dr. Fowler’s statement at the inquest, which I quoted earlier, would allow, given insanity, of equal rights to women. But I _felt_, from the beginning, that John Hoode had been killed by a man, and I worked throughout on that assumption. At every turn little things told me that this was a man’s work; and I was finally satisfied when I accepted the theory of descent by the wall. “I will bring to an end here the first part of this report. But before starting upon the next, I will summarise the conclusions already shown, give them life with a touch of imagination, and let you see the picture.