"Do you not see that they are different kinds of candle-grease? The pieces you picked up alongside the bed are tallow; mine, picked up from underneath the gas-globe, are wax." The Superintendent had not noticed the difference in the candle-grease, but he thought it beneath his dignity to examine them again. "The murderer may have had two candles," he said oracularly. "Anyway, what does it matter? They're both candle-grease." Colwyn swept his fragments back into his pocket with a quick impatient gesture. "Both candle-grease, as you say," he returned sharply. "We do not seem to be making much progress in our investigations, so let us discontinue them. Good-night." CHAPTER X Colwyn went to bed, but not to sleep. Hour after hour he lay awake, staring into the darkness, endeavouring to put together the facts he had discovered during the afternoon's investigations at the inn. But they resembled those irritating odd-shaped pieces of a puzzle which refuse to fit into the remainder no matter which way they are turned. Try as he would, he could not fit his clues into harmony with the police theory of the murder. On the other hand, he could not, nor did he attempt, to shut his eyes to the strong case against Ronald, for he fully realised that there was much to be explained in the young man's actions before any alternative theory to that held by the police could be sustained. But so far he did not see his way to an alternative theory. He sought vainly for a foundation on which to build his clues and discoveries; for some overlooked trifle which would help him to read aright the true order and significance of the jumbled assortment of events in this strange case. In the first place, was Ronald's explanation, about losing his way and wandering to the inn by chance, the true one? The police accepted it without question, but was it likely that a man who was in the habit of taking long walks about the coast would lose his way easily? As against that doubt, there were the statements of the innkeeper and the deaf waiter that they had never seen Ronald before. If Ronald were not guilty, why had he departed so hurriedly from the inn that morning? And if he were not the murderer what was the explanation of the damning evidence of the footprints leading to the pit in which the body of the murdered man had been flung? If the discovery of the two kinds of candle-grease in Mr. Glenthorpe's bedroom indicated that two persons were in the room on the night of the murder, who were those two persons, and what did they both go there for?