Stethoscope

The stethoscope is a medical device for listening to the sounds of the heart, lungs and intestines and to blood flow, a practice called auscultation. René Laennec invented it in 1816 at the Necker-Enfants Malades Hospital in Paris: a monaural wooden tube, devised after he found that a rolled piece of paper carried heart sounds without his ear touching the patient's chest. Golding Bird described one with a flexible tube in 1840, and Arthur Leared made a binaural stethoscope in 1851. George Philip Cammann's design of the following year, with a plug for each ear, has remained essentially unchanged since.