"Thanks. The next thing is about your nephew, Ronald. It appears to me to be almost an act of treachery to conceal from him what has occurred." "What good purpose would be served," asked Bob, "by disclosing it to him? He is blind, and could not assist us. By and by, perhaps, he may be of use, though I do not see in what way; at present it would only distress him to let him into the secret." "We will wait, then; but I shall call upon him to-morrow and have a little chat with him about Mr. Nisbet. It will be a busy day for all of us, and I shall be absent from the house till evening, but you will find me here when you come. Another thing that is in my mind is whether there is any special motive for Mr. Nisbet's return to London--any special motive, I mean, in relation to this mystery." "Impossible to say, Ned." "That is so. Well, we must wait. Now I think we have threshed matters out, and we will get to bed. I will just run out and post my letter to Mr. Dickson, and this exciting day's work will be over." We were all up next morning before seven o'clock, and after a hasty breakfast I told Barbara of our plans with respect to her. She was quite willing, and expressed her gratitude; her only trouble was about her sister Molly, who, she said, might come to the house in search for her when she was absent. It was not difficult to set her mind at ease upon this point, and she departed with Bob in perfect contentment. The first call I made--at ten o'clock--was upon Mr. Dickson. He had received my letter, and he informed me that the description I had given of Mr. Oliver Nisbet tallied exactly with that gentleman's appearance. He had not ascertained from what part of the Continent Mr. Nisbet had come, but he had learned that he had been abroad for some time past. Our relations with each other being now on a more confidential footing, I spoke to him about Dr. Cooper, and instructed him to keep his eye on the pettifogger. From his office I proceeded to the residence of Ronald Elsdale, and opened up a conversation with him, leading artfully to the subject upon which I desired information. "From certain events that have transpired lately," I said, "I am curious to learn something more of his character. Were you aware at the time of your intimacy with him that his stepdaughter was heiress to a large fortune?" No, he answered, he was not aware of it. From the manner in which they traveled he judged Mr. Nisbet to be a man of means, but he knew nothing further. "Respecting his acquirements," I said. "Was he of a scientific turn of mind?"