When we had done full justice to the refreshments put before us we came away pledged to attend the first At Home given by our hostess, which she explained would be as soon as she was out of mourning for her brother. I think she had won both our hearts in spite of her eccentricities, and we entertained no serious dread that her murderous propensities would be indulged at our expense. Tarleton was very silent till we were back at Montague Street. Even when we were in his study again he did not seem much disposed to discuss the new situation with me. For the first time since the beginning of the investigation I had the impression that I was not entirely in his confidence. When I expressed my curiosity as to Weathered’s motive for stealing the bottle of upasine he lifted his bushy eyebrows and looked at me almost as if he were annoyed. “We don’t know that he did steal it,” he growled. “Everyone who read Armstrong’s book knew of his discovery, and would expect to find some of the new poison among his belongings. And as for that little woman, she has probably babbled about it to a dozen persons whom she has forgotten. Her memory is like a sieve.” The judgment struck me as harsh. Mrs. Baker certainly had a genius for forgetting names, but so have many people whose memories are good enough in other respects. It seemed to me that she had shown a pretty fair recollection of her dealings with Weathered at all events; and I said so. Tarleton hunched himself up in his favourite armchair and growled again. “You ask me to believe that a doctor who had stolen what he knew to be a deadly drug, and who was actually taking precautions to prevent himself being poisoned at the time, was careless enough to let it be taken from him?--Well, I don’t.” I had never known him to speak so irritably before. I sat dumb, asking myself what was in his mind. And all at once the explanation flashed upon me. If he didn’t believe that Weathered had taken the fatal bottle he must have been searching for the probable thief among Weathered’s enemies. The last question he had put to Mrs. Baker showed that his thoughts had turned for a moment in the direction of the Frenchwoman, who of all others had the best opportunity to administer the poison. Who else was left? The one enemy of Weathered’s whom we both knew of, the one person who had not only a reason but, it might be said, a moral right to take his life in self-defence was Violet Bredwardine. And she had confessed to having lent the disguise worn on the night of the murder by one who must have been her friend, and probable champion. A dozen trifling incidents rushed back into my mind; the specialist’s anxiety lest his own bottle should have been tampered with; the way he had contrived--it looked like contrivance to me now--to give me a chance of meeting Violet alone. There could be only one meaning in it all.