Answer:
Lighter than what I am made of, More of me is hidden Than is seen.
A shimmering field that reaches far. Yet it has no tracks, And is crossed without paths.
In the night a mountain, in the morning a meadow.
It is able to speak because it has a hard gone. You know what it is as soon as it has sung. What is it?
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard. Who am I?
What never gets any wetter no matter how hard it rains?