Unusual extra long monaural stethoscope dating from 1860. This piece was made in England out of fruitwood. French physician, Rene Theophile Hyacinthe Laennec invented the monaural stethoscope in 1816. This design, which is essentially a wooden cylinder with a hole bored out down the centre, was the earliest form of diagnostic device for listening to internal sounds of the body (auscultation).