John Cage
In 1951 the composer John Cage visited the anechoic chamber at Harvard University. An anechoic chamber is a room designed in such a way that the walls, ceiling and floor absorb all sounds made in the room, rather than reflecting them as echoes. Such a chamber is also externally sound-proofed. Cage entered the chamber expecting to hear silence. He wrote later - I heard two sounds, one high and one low. When I described them to the engineer in charge, he informed me that the high one was my nervous system in operation, the low one my blood in circulation.
