The stethometer consists of a frame formed of two parallel steel bars joined by a third at one end. At the free end of the bars is attached a leather strap, by means of which the apparatus may be suspended from the neck. Attached to the inner end of one bar is a tambour and ivory button, to the end of the other an ivory button. When in use, the apparatus is suspended with the transverse bar posteriorly, the button of the tambour is placed on the part of the chest the movement of which it is desire to record, and the other button is made to press upon the corresponding side of the chest, so that the chest is held between a pair of callipers.

Stethometer

The stethometer consists of a frame formed of two parallel steel bars joined by a third at one end.…