The Amplification and Recording of Fœtal Heart Sounds [Abridged]

Discussion on the Uses of the Cardiophone in the Labour Ward

“…Seven years ago Gunn and Wood projected the sounds of the feetal heart from a loud speaker in this hall (see Gunn and Wood, 1953). When I brought a loud speaker into the labour ward, however, I found that interference from adventitious sounds and feed-back were greatly intensified.…”