"Reginald Henson. Mind you, I had no more idea of it than the dead when I went to Longdean Grange to-night. I went there because I had begun to suspect who occupied the place and to try and ascertain how the Rembrandt engraving got into 218, Brunswick Square. Miss Gates must have heard us talking over the matter, and that was why she went to Longdean Grange to-night."
"I hope she got home safe," said David. "The cab man says he put her down opposite the Lawns."
"I hope so. Well, I found out who the foe was. And I have a pretty good idea why he played that trick upon me. He knew that Enid Henson and myself were engaged; he could see what a danger to his schemes it would be to have a man like myself in the family. Then the second Rembrandt turned up, and there was his chance for wiping me off the slate. After that came the terrible family scandal between Lord Littimer and his wife. I cannot tell you anything of that, because I cannot speak with definite authority. But you could judge of the effect of it on Lady Littimer to-night."
"I haven't the faintest recollection of seeing Lady Littimer to-night."
"My dear fellow, the poor lady whom you met as Mrs. Henson is really Lady Littimer. Henson is her maiden name, and those girls are her nieces. Trouble has turned the poor woman's brain. And at the bottom of the whole mystery is Reginald Henson, who is not only nephew on his mother's side, but is also next heir but one to the Littimer title. At the present moment he is blackmailing that unhappy creature, and is manoeuvring to get the whole of her large fortune in his hands. Reginald Henson is the man those girls want to circumvent, and for that reason they came to you. And Henson has found it out to a certain extent and placed you in an awkward position."
"Witness my involuntary guest and the notes and the cigar-case," David said. "But does he know what I advised one of the girls—my princess of the dark room—to do?"
"I don't fancy he does. You see, that advice was conveyed by word of mouth. The girls dared not trust themselves to correspondence, otherwise they might have approached you in a more prosaic manner. But I confess you startled me to-night."
"What do you mean by that?"
"When you sent me that note. What you virtually asked me to do was to countenance murder. When I went into the sick room I saw that Christiana Henson was dying. The first idea that flashed across my mind was that Reginald Henson was getting the girl out of the way for his own purposes. My dear fellow, the whole atmosphere literally spoke of albumen. Walker must have been blind not to see how he was being deceived. I was about to give him my opinion pretty plainly when your note came up to me. And there was Enid, with her whole soul in her large eyes, pleading for my silence. If the girl died I was accessory after and before the fact. You will admit that that was a pretty tight place to put a doctor in."
"That's because you didn't know the facts of the case, my dear Bell."