"I thought a dog had helped, Wigan; that was my theory," said Quarles as we went back to town. "I noted that a dog had trodden on the polished skirting near the study sofa. Miss Wickham might have had a dog, that is why I questioned the housemaid so closely to make sure she entered the house quite alone. When we were brought in contact with Marsh I suspected Mrs. Seligmann. Those glasses I wear sometimes are curious, acting like opera-glasses, and they enabled me to see a portrait of Mrs. Seligmann standing back on a corner table, and, moreover, that it was signed. Marsh evidently knew her well; was in love with her, perhaps, and she with him. My saying that he had first been to River Mansions in the morning was guesswork, but by his not denying it, the fact was established that the papers must have come into his possession, or why should he have gone there? He must have known that Miss Wickham usually went away on Saturday or Sunday and did not return till late on Monday. I argued that Mrs. Seligmann might have sent them, and that Marsh suspected this, hence his visit to Miss Wickham to make certain. It may be true that he did not know she was going to Seligmann on Saturday night, and if he heard from the porter that she had left town on Saturday afternoon he would know that the papers could not have come from her. He would hear from the porter that she had returned in the small hours of Sunday morning, and when, later in the day, he read of the murder he would not know what to think. It is also possible, Wigan, that Seligmann expected his wife to call for him that night. That their motor had broken down on the way up to town makes it even probable. I went to Maidenhead to see if Mrs. Seligmann had a dog, a savage brute who would attack at her command, savage but small. The great brute in the yard did not fit my theory. God knows I didn't suspect the real truth. Strange that I should have felt that I was in a forest, stranger still that Zena should speak of Pan. I don't explain, Wigan, I can't, but it has happened--a return of the human to wild and awful atavism. She meant to kill, to rid herself of the man who was in her way. The human in her used the stiletto or hatpin, the animal in her used claws. She will be called mad, and so she is in one sense, but not in another; nor was it murder in the true sense of the word. The wild wolf does not murder; he kills because he must. Even the dog recognized an enemy of whom he was afraid. The beast was not ill, but cowed, and snapped at her as you heard the chauffeur say. Had she had her way with me to-day, I should have looked like poor Seligmann."