1926. German playwright and author Bertolt Brecht writes "The Radio as an Apparatus of Communication". He notes:
"Radio is one sided when it should be two. It is purely an apparatus for distribution, for mere sharing out. So here is a positive suggestion: change this apparatus over from distribution to communication. The radio would be the finest possible communication apparatus in public life, a vast network of pipes. That is to say, it would be if it knew how to receive as well as transmit, how to let the listener speak as well as hear, how to bring him into a relationship instead of isolating him. On this principle the radio should step out of the supply business and organise its listeners as suppliers."
Yet again, it's not difficult to see the parallels between radio and the internet.
Found in these good essays on the history of radio and art:
Radiocasting: Musings on Radio and Art
Archeological Exploration - A short trip in the history of radio-oriented art