Classic Poem

Over known fields with an old friend in dream
I walked, but came sudden to a strange stream.
Its dark waters were bursting out most bright
From a great mountain's heart into the light.
They ran a short course under the sun, then back
Into a pit they plunged, once more as black
As at their birth: and I stood thinking there
How white, had the day shone on them, they were,
Heaving and coiling. So by the roar and hiss
And by the mighty motion of the abyss
I was bemused, that I forgot my friend
And neither saw nor sought him till the end,
When I awoke from waters unto men
Saying: " I shall be here some day again."