"The murderer didn't get in that way," he said. "On the face of it, it seems a plausible theory to suggest that he entered by the locked door and hid himself somewhere in this wing, and escaped after committing the murder by jumping through the bedroom window. But it is impossible to get over your point that if he had entered by the door he would have tried to escape by the same means, not knowing that the door had been locked in the meantime. To do that he must have traversed the corridor twice and gone down and up these back stairs while the guests were coming up the other stairs. He couldn't have done it in the time. He would have been caught--cut off before he could get back. Look at this steep flight of stairs and the length of the corridor! That disposes of the incident of the door. Whoever unlocked it was not the murderer." Merrington retraced his steps along the corridor. As he walked, his eyes roved restlessly over the tapestry hangings and velvet curtains, and took in the dark nooks and corners which abound in old English country-houses. "Plenty of places here where a man might hide," he muttered, in a dissatisfied voice. At the head of the front staircase he paused, and looked over the balusters, as though calculating the distance to the hall beneath. Then he descended the stairs. It still wanted half an hour to breakfast time. There was no sign of anybody stirring downstairs except a fresh-faced maidservant, who was dusting the furniture in the great hall. She glanced nervously at the groups of police officials, and then resumed her dusting. Merrington strode across to her. "What is your name, my dear?" he asked, in his great voice. "Milly Saker, sir." "Very well, Milly. I'll come and have a talk with you presently--just our two selves." The girl, far from looking delighted at this prospect, backed away with a frightened face. Merrington strode on through the open front door, and turned towards the left wing. It was a crisp autumn morning. The early sunshine fell on the hectic flush of decay in the foliage of the woods, but a thin wisp of vapour still lingered across the moat-house garden and the quiet fields beyond. Merrington kept on until he reached the large windows of the dining-room, which opened on to the terraced garden. "That's Mrs. Heredith's window," he said, pointing up to it. "Her bedroom is directly over the dining-room. If the murderer escaped by the window he must have dropped on to this gravel path." "It is a pretty stiff drop," said Captain Stanhill, measuring the distance with his eye. "Oh, I don't know," replied Merrington. "He'd let himself down eight feet with extended arms, and that would leave a drop of only ten feet or thereabouts--not much for an athletic man. But if he dropped he must have left footprints." "There are none. I have looked," said Caldew.