The Hound of the Baskervilles

Sherlock Holmes waved our strange visitor into a chair. "You are an enthusiast in your line of thought, I perceive, sir, as I am in mine," said he. "I observe from your forefinger that you make your own cigarettes. Have no hesitation in lighting one." The man drew out paper and tobacco and twirled the one up in the other with surprising dexterity. He had long, quivering fingers as agile and restless as the antennae of an insect. Holmes was silent, but his little darting glances showed me the interest which he took in our curious companion. "I presume, sir," said he at last, "that it was not merely for the purpose of examining my skull that you have done me the honor to call here last night and again today?"