In the early 1800s, an invention came along that changed everything. Suddenly the doctor could clearly hear what was happening inside the body. The heart, the lungs, the breath. This revolutionary device was the stethoscope.

The inventor of the stethoscope was a French doctor named René Laennec. In medical school, he had learned to practice percussion – a technique in which doctors tap their fingers against a patient’s chest and listen to the sound to try and hear what’s going on inside. {listen}