Here I may mention a fact which I had not discovered at first. Whenever he was interested in a case I was always taken into his empty room; at other times we were in the dining-room or the drawing-room. It was the empty room on this occasion, and Zena remained with us. I went carefully through the case point by point, and he made no comment until I had finished. "The foreign cut of the clothes may be of importance," he said. "I am not sure. Is this wood you mention of any great extent?" "No, it runs beside the road for two or three hundred yards." "Toward Withan?" "No; it was near the Withan end of it that the dead man was found." "Any traces that the head was carried to the wood?" "The local authorities say, 'Yes,' and not a trace afterward. The ground in the wood was searched at the time, and I have been over it carefully since. Through one part of the wood there runs a ditch, which is continued as a division between two fields which form part of the farm land behind the wood. By walking along this the murderer might have left the wood without leaving tracks behind him." "A good point, Wigan. And where would that ditch lead him?" "Eventually to the high road, which runs almost at right angles to the Withan road." "Much water in the ditch?" asked Quarles. "Half a foot when I went there. It may have been less at the time of the murder. The early part of January was dry, you will remember." "There was a moon that night, wasn't there?" "Full, or near it," I returned. "And how soon was the alarm raised along the countryside?" "That night. It was about eight o'clock when the body was found, and after going to the village the farmer returned to Medworth for the police." "A man who had walked a considerable distance in a ditch would be wet and muddy," said Zena, "and if he were met on the road carrying a bag he would arrest attention." "Why carrying a bag?" asked Quarles. "With the head in it," she answered. "That's another good point, Wigan," chuckled Quarles. "Of course, the head may be buried in the wood," said Zena. Quarles looked at me inquiringly. "I searched the wood with that idea in my mind," I said. "One or two doubtful places I had dug up. I think the murderer must have taken the head with him." "To bury somewhere else?" asked Quarles. "Perhaps not," I answered. "A mad doctor bent on brain experiments--is that your theory, Wigan?" "Not necessarily a doctor, but some homicidal maniac who is also responsible for the Normandy murder. The likeness between the two crimes can hardly be a coincidence." "What was the date of the French murder?" "January the seventeenth." "Nearly the same date as the English one," said Zena. "Two years intervening," I returned. "Wigan, it would be interesting to know if a similar murder occurred anywhere in the intervening year at that date," said Quarles. "You have a theory, professor?"