© Science Museum/Science and Society Picture Library
The invention of the stethoscope by René Laënnec in 1816 contributed to of the revolution in medicine which occurred in Paris in the first decades of the nineteenth century. This gave rise to a new concept of disease, as a set of observable changes in specific organs of the human body, which could be confirmed by undertaking postmortems on patients who had died. The resulting model became the basis for modern diagnostic medicine. Many instruments were later devised to examine the body and identify disease. Laënnec's work was particularly concerned with tuberculosis, the disease from which he died in 1826.