TY  - JOUR
T1  - A stethoscope of increased sensitiveness
AU  - Donaldson JB
Y1  - 1919/10/25
N1  - 10.1001/jama.1919.02610430051027
JO  - Journal of the American Medical Association
SP  - 1303
EP  - 1303
VL  - 73
IS  - 17
N2  - 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.
SN  - 0002-9955
M3  - doi: 10.1001/jama.1919.02610430051027
UR  - http://dx.doi.org/10.1001/jama.1919.02610430051027
ER  -