In September 1816 a young doctor in Paris, René Laennec, was asked to examine a young woman with heart trouble. The usual method was to press your ear to the patient’s chest, and he couldn’t do it: her age and sex made it improper, he wrote later, and her build would have made it useless anyway. So he rolled a few sheets of paper into a tight tube, set one end on her chest and the other at his ear, and heard her heart more clearly than he had ever heard one with his ear against the skin. Within days he was turning wooden cylinders on a lathe. He called the thing a stethoscope, Greek for “chest-viewer”, which is an honest name: it let a doctor look inside a person without opening anything. I like that one of medicine’s most familiar instruments came out of embarrassment. Good manners asked for a little distance, and the distance turned out to be where the information was.