I had terrible insomnia last night and I'm sitting here now tired but still unable to sleep, and my mind is wandering into strange places.
I'm trying to find a book. Hopefully someone will recognize the half-assed description.
Many decades ago when I was in grade school, I read this book in the school library that was basically a collection of scenes from different books. One of them was this scene where these people in a community were living on rafts that floated endlessly through this underground river system. They never saw the sun and the kid who was the hero/heroine (I can't remember the gender) would swim between the rafts. One day, he/she decided to try and see more of the world and left the rafts. That's where the scene ended and I've been wanting to read the rest of it for about thirty years.
Does this twig a memory for anyone?