A STETHOSCOPE OF INCREASED SENSITIVENESS

To the Editor: —Recently I thought of a means of making a more sensitive instrument out of a Ford or similar bell stethoscope by fitting a rubber diaphragm (such as the rubber cap from a packing strip test tube) over the bell of the stethoscope. These are inexpensive and serve the purpose very well. A more durable diaphragm might be made of vulcanized rubber, celluloid or metal with a retaining coiled spring of wire situated above the diaphragm on the bell, holding the diaphragm firmly in place against the bell.