The harmonica. Like the children enchanted by the piper, you feel an urge to follow the music, and just like them you are led out into deep water. Yet you are not detached from logic: the instrument is probably played by a culturally minded person who would willingly and kindly guide you to the publisher’s office. Not a bad thought, you think, but you mostly follow the feeling, climb the stairs with excitement and do not even notice the colossal trilobite fossil on the fourteenth step.