The other day—Thursday, to be more exact—Dr. Mortimer lunched with us. He has been excavating a barrow at Long Down and has got a prehistoric skull which fills him with great joy. Never was there such a single-minded enthusiast as he! The Stapletons came in afterwards, and the good doctor took us all to the yew alley at Sir Henry’s request to show us exactly how everything occurred upon that fatal night. It is a long, dismal walk, the yew alley, between two high walls of clipped hedge, with a narrow band of grass upon either side. At the far end is an old tumble-down summer-house. Halfway down is the moor-gate, where the old gentleman left his cigar-ash. It is a white wooden gate with a latch. Beyond it lies the wide moor. I remembered your theory of the affair and tried to picture all that had occurred. As the old man stood there he saw something coming across the moor, something which terrified him so that he lost his wits and ran and ran until he died of sheer horror and exhaustion. There was the long, gloomy tunnel down which he fled. And from what? A sheep-dog of the moor? Or a spectral hound, black, silent, and monstrous? Was there a human agency in the matter? Did the pale, watchful Barrymore know more than he cared to say? It was all dim and vague, but always there is the dark shadow of crime behind it.