"My first impression as I opened the door was that a fire had broken out, for the room was so filled with smoke that the light of the lamp upon the table was blurred by it. As I entered, however, my fears were set at rest, for it was the acrid fumes of strong coarse tobacco which took me by the throat and set me coughing. Through the haze I had a vague vision of Holmes in his dressing-gown coiled up in an armchair with his black clay pipe between his lips." -
  --  Sir Arthur Conan Doyle