The sound of water

The post Wireless Fruitman started a (sort of) interesting discussion about wireless chains. What follows is a piece of it:
"...the WC makes a noise after you "pull the chain"... it's the noise of the water filling the diposit. i love to go to bed and hear this noise, hear the sound of the water, lighter and lighter, until it vanishes, and I fall asleep. it's a kind of urban river..."