There's music in the air

There's music in the air
That was sung long ago.
It flits about and floats about
To find a place to go, a place to go.
And if you are a trumpet,
Then it will make you blow,
And if you are a fiddle
It will dance upon your bow.
If you are a piano,
You will laugh on ev'ry string,
And if you are a girl or boy,
You'll sing.