Answer:
What comes down but never back goes up?
What goes up and down without moving?
Mouth up it gets filled, mouth down it gets empty.
Tall, I am young. Old, I am short. With life I glow. Anemoi is my foe.
There is one in every corner and two in every room.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.