This frightened him, and between the fear of the threat and the fear that you might already know more than he suspected, he authorised me--he was even eager about it--to come and see you; always, of course, under a pledge of strict professional secrecy." "So far your account is quite clear, Mr. Potswood," Hewitt said. "You have done your best, now I must do mine. You wish me to see Mason at once, no doubt?" "I arranged to bring you to his house, if you were willing and your engagements permitted, at three this afternoon. Will that do? I have been keeping you, I see--it is past one already. Will you lunch with me at my club?" "With great pleasure--more especially as I have a few questions to ask as we go along. Is it far?" "Just at this end of Pall Mall--we will walk, if you like." "Tell me now," said Hewitt as they went, "anything you know about Mr. Mason's habits, family connections, and so forth, as fully and as minutely as you please. Has he any friends connected with China, for instance?" "China? Why, no, I think not; except--but I'll tell you all I know. Mr. Mason has no family connections, so far as I am aware--at any rate, in London--except his niece, Miss Creswick. She is within a few months of twenty-one, a charming girl, but horribly shut in, for Mason has almost no visitors. Miss Creswick was his sister's daughter; she lost her mother first and then her father, and was left to the guardianship of her uncle. He was also trustee under the will, and he has, I believe, discretion to keep charge of her property, if he thinks fit, till she reaches the age of twenty-five; though in case of his death she is to inherit in the ordinary way, on coming of age. She is a very dutiful and, indeed, an affectionate niece; though I must say he is scarcely fair to her, keeping her, as he does, so completely secluded from the society of young people of her own age. Mere thoughtlessness, I think; he has had no children of his own, his mind is wholly occupied with his science and his fads, and he makes himself a recluse without a thought of the girl. And that brings me to what I was about to say at first, when you asked me if Mr. Mason had any friends connected with China. There is a young doctor--Lawson is his name--some very distant connection of the family, I think, who had a professional appointment of some sort in Shanghai for a year or two, but who is now in London trying to work up a small practice of his own. If you hadn't mentioned China I shouldn't have thought of him, since he never goes to the house now--or, at any rate, is supposed not to go." "Doesn't go to the house? And why is that?"