text: Sherlock Holmes had, in a very remarkable degree, the power of detaching his mind at will. For two hours the strange business in which we had been involved appeared to be forgotten, and he was entirely absorbed in the pictures of the modern Belgian masters. He would talk of nothing but art, of which he had the crudest ideas, from our leaving the gallery until we found our selves at the Northumberland Hotel.
  The book showed that two names had been added after that of Baskerville. One was Theophilus Johnson and family, of New castle; the other Mrs. Oldmore and maid, of High Lodge, Alton.
  "Surely that must be the same Johnson whom I used to know," said Holmes to the porter. "A lawyer, is he not, gray headed, and walks with a limp?"
  "Thank you; I am afraid I cannot claim her acquaintance. We have established a most important fact by these questions, Wat son," he continued in a low voice as we went upstairs together. "We know now that the people who are so interested in our friend have not settled down in his own hotel. That means that while they are, as we have seen, very anxious to watch him, they are equally anxious that he should not see them. Now, this is a most suggestive fact."
  "That's just what I do mean to say. I only had three pairs in the world -- the new brown, the old black, and the patent leath ers, which I am wearing. Last night they took one of my brown ones, and to-day they have sneaked one of the black. Well, have you got it? Speak out, man, and don't stand staring!"
  "Dear me! It is a stake for which a man might well play a desperate game. And one more question, Dr. Mortimer. Suppos ing that anything happened to our young friend here -- you will forgive the unpleasant hypothesis! -- who would inherit the estate?"
  "If matters came to a crisis I should endeavour to be present in person; but you can understand that, with my extensive con sulting practice and with the constant appeals which reach me from many quarters, it is impossible for me to be absent from London for an indefinite time. At the present instant one of the most revered names in England is being besmirched by a black mailer, and only I can stop a disastrous scandal. You will see how impossible it is for me to go to Dartmoor."
  The ring at the bell proved to be something even more satis factory than an answer, however, for the door opened and a rough-looking fellow entered who was evidently the man himself.
  Holmes cast a swift glance of triumph at me. "Oh, he men tioned his name, did he? That was imprudent. What was the name that he mentioned?"