National Geographic : 1947 Mar
U iaronal ,eograpnlc orieiy Charting Her Head Shape Makes Her Headset Fit Better Seeking a more comfortable operator's headset, scientists measured skull con tours with this device, nicknamed "crown of thorns." It showed human heads vary from almost flat to dome-shaped; so headsets were made adjustable. Ektachromes by Willard R. Culver Bells That Ring Your Telephone Are Tuned toMeet Your Needs A scientist mounts gongs on aturntable on which they revolve. The arm at left swings a microphone inan arc topick up the sound from all angles for analysis of the bells' quality and power.