Rene Theophile Hyacinthe Laennec (1781-1826), the French physician who invented the stethoscope. He studied at the Charite Hospital in Paris and qualified as a doctor in 1804. It was well known at the time that listening to chest sounds (auscultation) and tapping the chest (percussion) were useful in diagnosis. In 1816, as an aid to this, Laennec made his first stethoscope, a wooden tube 30 centimetres long which was used to connect the chest of the patient with the ear of the doctor. He was able to link chest sounds with a range of diseases, and described his results in his book On Mediate Auscultation (1819).