Stethoscope, 20th century.

Made by Down Bros of London. The stethoscope was first devised in 1816 by the French physician, Rene Laennec (1781-1826) and was constructed from a simple hollow tube. Stethoscopes were designed to help the physician diagnose diseases of the lungs, heart and vascular systems by listening to the internal rhythms and sounds of the human body. The familiar binaural (two ear) stethoscope, such as this example, was developed in the 1850s.