Rides high; then all the upper air they fill

With roaring sound, that ceases not to flow,

Like smoke, along the level of the blast,

In mighty current; theirs, too, is the song

Of stream and headlong flood that seldom fails;

And, in the grim and breathless hour of noon,

Methinks that I have heard them echo back

The thunder's greeting. Nor have nature's laws

Left them ungifted with a power to yield

Music of finer tone;[191] a harmony,