Before about 1919, when a doctor wished to listen to a patient's chest, he had to press his ear right onto the skin of the chest.
The first stethoscopes, invented in Paris, were monaural: originally just a tube, later a bell shape was added at one end an an earpiece at the other. The binaural stethoscope was not invented until the 1850's.
This stethoscope, whose overall length is about 14.5", is basically a piece of broomstick with the other bits added. The broomstick is glossy black, the earpiece is ivory-coloured, as a real one would have been ivory. The bell-shape is painted as brass.
The earpiece is a wood turning that was on sale in the crafts area of a fabric store.
The "bell" is the part of a wooden candlestick that was cut off and discarded in the making of the mandolins, two years previously.
The odd thing about this particular stethoscope was needed because, in the play, the doctor must listing to his own chest and diagnose himself. The actor was a big man, and that set the length of the stethoscope. And it meant that the bell of the instrument had to be able to be turned at right angles to the length. Although this was my own invention, it is so sensible that I expect that there were real instruments that did have this feature.