Answer:
A shimmering field that reaches far. Yet it has no tracks, And is crossed without paths.
What turns from red to black as soon as it touches water?
This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has hands; lacks a head but has a face.
You throw me out when you want to use me and you take me in when you don't want to use me. Who am I?
What measures out time. Until in time all is smashed to it?
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.