He reflected that his only tangible reason, so far, for not accepting the police theory was based on the belief that two people had been in the murdered man's room, and that belief rested on the discovery of a spot of candle-grease which in itself was merely presumptive, but not conclusive evidence. It was necessary to establish beyond doubt the supposition that two people had been in the room before he could presume to draw inferences from it. And, if he succeeded in establishing that supposition, might not Ronald have been one of the two persons, and the actual murderer? What was the significance of the broken incandescent burner, the turned-on gas, and the faint mark under the window? These questions revolved in Colwyn's head in a circle, always bringing him back to his starting point that the solution of the case did not lie on the surface, and that the police theory could not be made to fit in with his own discoveries. The latter were in themselves internal evidence that the whole truth had not yet been brought to light. Gradually the line of the circle grew nebulous, and Colwyn was fast falling asleep through sheer weariness, when a slight sharp sound, like that made by turning a key in a lock, brought him back to wide-eyed wakefulness. He sat up in bed, listening with strained ears, feeling for the box of matches at his bedside. He found them, and endeavoured to strike a light. But the matches were war matches, and one after another broke off in his hand against the side of the box. He tried holding the next close to the head, but the head flew off. With a muttered malediction on British manufacturers, Colwyn struck several more in rapid succession before he succeeded in lighting the candle at his bedside. He got quietly out of bed, and, leaving the candle on the table, opened his door noiselessly and looked out into the passage. He had been put to sleep in a small bedroom in the deserted upstairs wing where the murder had been committed. His room was opposite the lumber room, which was three doors away from the room in which the body of the dead man lay. When the question of accommodation for Superintendent Galloway and himself had been discussed, the former had chosen to have a bed made up in the bar parlour downstairs as more comfortable and snug than any of the bedrooms upstairs, but Colwyn had consented to sleep in the deserted wing. The innkeeper, who had lighted him upstairs, had apologised for the humble room and scanty furniture, but Colwyn had laughingly accepted the shortcomings of the room as a point of no importance, and had stood at his door for some moments watching a queer effect in shadows caused by the innkeeper's candle throwing gigantic wavering outlines of his gaunt retreating figure on the bare stone wall as he went down the side passage to his own bedroom.