Monaural stethoscope, designed by French doctor, Pierre Piorry, dating from 1850. The chest piece (bell shaped end) and ear piece (flat end) are made from ivory and the stem is made from fruitwood. The design of the monaural stethoscope is essentially a wooden cylinder with a hole bored out down the centre, it was the earliest form of diagnostic device for listening to internal sounds of the body (auscultation).