Since the time of Hippocrates, doctors have listened directly to patient’s chests for knowing cardiac or chest  problems. The other type of diagnostic method used by the physicians in early days was the pulse palpitation measurements developed by the  physician Charaka, the father of Indian medicine. In fact the inventor of the stethoscope was a young French Physician namely Renee Theophile-Hyacinthe Laennec. The story goes like this.

            One day Laennec was examining an obese young woman for tuberculosis. He felt very uneasy to put his head against the chest of the woman. He was very much embarrassed while examining the lady without turning away the patient from his clinic. He came up with a brilliant idea for stethoscope prototype. He remembered a trick he had learned as a child that sound travels through solids, and so he rolled up several sheets of paper , placed one end to his ear and the other end to the woman’s chest. He was very happy to discover that sounds were not only conveyed through the paper, but they were also louder and more clearer.

Laennec’s Stethoscope

            In the year 1816 Laennec made the first stethoscope for medical use. He made the instrument from a turned piece of wood, hollow in the center. It was made of two pieces. One end had a hole to place against the ear, and the other was hollowed out into a cone . There was a third piece that fitted into this corner, which had a hollow brass cylinder placed inside it. This piece was placed in the stethoscope to listen to the heart, and lungs. Laennec preferred to call it as ‘Le cylinder’ .This is also called Leanne’s ear. It was later named as ‘stethoscope’ which is derived from the Greek words ‘stethos’ for chest and ‘skopeein’ meaning to inspect. Hence the name-stethoscope means  to inspect the heart. In 1819, he published a book titled “ De l’  Auscultation Mediate meaning ‘ A Treatise on Diseases of the Chest and Mediate Auscultation ‘. He described two varieties of normal breath sounds ( vesicular and bronchial)  and  various adventitious sounds. He also worked on heart sounds as well. He described the first and  second heart sounds, cariac irregularities caused by ectopic beats, and murmurs resulting from valvular diseases. Hence Laennec is known as the father of stethoscope.

Piorry’s Stethoscope

            There were several modifications and further improvements in Laenner’s stethoscope over the next few years. The most notable was Pierre Adolphe Piorry ( 1794-1879) in 1828, as Piorry also incorporated another diagnostic instrument, known as a ‘pleximeter’ into stethoscope . Piorry’s model was about half the size of Laennec’s and was trumpet shaped, made of wood with removable ivory earpiece and chest piece.

Nocholas Comins Stethoscope

In the early part of 1850 many people tried to modify Laennec’s stethoscope. In 1829, Nicholas Comins devised a stethoscope that he described as ‘bect tube’ having several hinges, which allowed the physician to examine the patient easily and suggested the making of a binaural stethoscope. However, the first commercially marketed binaural model was that of Marsh of Cincinnati, USA in 1851. His model contained the first recorded chest piece.

George Cammann’s Stethoscope

In 1855 George Cammann of New York produced the first recognized usable binaural stethoscope. He actually perfected the model of binaural stethoscope Cammann’s model with ivory earpiece connected to metal tubers. These were held together by a simple hinge joint, and tension was applied by way of an elastic band. Attached to these were two tubes covered by wound silk. These converged into a hollow ball designed to amplify the sound, and attached to the ball was a conical , bell chest piece. Cammann’s model was endorsed in 1866 by Austin Flint and soon it became widely used. It was sometimes sold as a set, with a pleximeter and precursor.

Charles Denison Stethoscope

In 1885 , Charles Denison came out with an entirely new model based on Bartlett’s Laennec. His model was based on the idea of funneling sound to ears , much like the monaural. His earpieces were made of hard rubber, which led into woven tubes and a large chest piece. It came with three interchangeable chest pieces for hearing different types of sounds. The tension between the earpiece was accomplished by a screw mechanism . Denison’s model was widely accepted.

Ford’s Bell Stethoscope

The next land mark in the improvement of the stethoscope was of Ford’s Bell chest piece in 1885. This very simple model was made of steel with gutta-percha , ebony or even ivory base. It funneled sound into two tubes, usually made of rubber, which led to the earpiece. Another stethoscope called the Wincarnis stethoscope which allowed the listener to vary the loudness and quality of the sounds conveyed .

                                                                                                             Although the stethoscope has remained relatively unchanged since 1930, several different experiments were designed later. The electronic stethoscope is now available in the  market. The stethoscope has opened new worlds to the art of diagnosis, and it shall always remain one of the most valuable diagnostic tools in the history of mankind.