John Cage performing "Water Walk" in January, 1960 on the popular TV show I've Got A Secret.
"At the time, Cage was teaching Experimental Composition at New York City's New School. Eight years beyond 4:33, he was (as our smoking MC informs us) the most controversial figure in the musical world at that time. His first performance on national television was originally scored to include five radios, but a union dispute on the CBS set prevented any of the radios from being plugged in to the wall. Cage gleefully smacks and tosses the radios instead of turning them on and off.