Answer:
The more of it there is, the less you see.
What goes up when the rain comes down?
They made me a mouth, but didn't give me breath. Water gives me life, but the sun brings me death.
In your fire you hear me scream, creaking and whining, yet I am dead before you lay me in your hearth.
What goes through a door but never goes in. And never comes out?
I'm the source of all emotion but I'm caged in a white prison.