"A very beautiful and elegantly dressed lady who had been a bit more friendly than the others came towards the pool and the burbling of the water changed into wonderful soft music. I’d never heard such strange sounds before. As I came closer to the lady I was astonished to see that she was playing a keyboard which was connected to the pool. The keys operated openings which sometimes let water fall onto crystal bells and created marvellous harmonies. Sometimes the water came out in a fast but intermittent stream, which produced a sound like the roar of angry waves brought into a wild but perfect harmony. Sometimes the flow was calm and then it was as if full chords were flying in from far away. Sometimes the stream dissolved into little splashes against the crystal glass from which we could hear a quiet melodic babbling. The instrument was called a hydrophone, recently invented here and still not widely used."
"The Year 4338: Petersburg Letters"