Most of the photos on this site were extracted from reference images (high-resolution tiffs, 20 to 200 megabytes in size) from the Library of Congress research archive. (To query the database click here.) Many were digitized by LOC contractors using a Sinar studio back. They are adjusted by your webmaster for contrast and color in Photoshop before being downsized and turned into the jpegs you see here.
September 13, 1938. "What next? Unborn baby's heartbeat broadcast from Washington hospital. As part of an educational program, the heartbeats of an unborn baby were broadcast today from Georgetown University Hospital. This was made possible by the use of a specially designed microphone placed on the chest of the expectant mother, Addie Gonyea, shown with (left to right) Dr. J.G. Burd, Dr. John Cavanagh, announcer Bill Coyle of the N.B.C. and Dr. Henry B. Gwynn." Harris & Ewing Collection glass negative. View full size.