Answer:
I fly through the air on small feathered wings, seeking out life and destroying all things.
A little pool with two layers of wall around it. One white and soft and the other dark and hard. Amidst a light brown grassy lawn with an outline of a green grass.
Bright as diamonds, Loud as thunder, Never still, A thing of wonder.
What is the thing which, once poured out, cannot be gathered again?
A leathery snake, with a stinging bite. I'll stay coiled up, unless I must fight.
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.