National Geographic : 1954 Jul
@ National Geographic Society 106 Walls 8 Feet Thick Surround Bell Laboratories' Weird Room of Silence Here scientists can study pure sound. Deep Fiberglas wedges in the walls of this free space room, or anechoic chamber, stifle every echo and eliminate all outside noises. The utter silence is oppressive to some, frightening to others. Visitors are often startled to hear their hearts beating and clothes stretching as they breathe.