And now this spell was snapt: once more
I viewed the ocean green,
And look'd far forth, yet little saw
Of what had else been seen-

Like one that on a lonesome road
Doth walk in fear and dread,
And having once turn'd round, walks on,
And turns no more his head;
Because he knows a frightful fiend
Doth close behind him tread.

Coleridge:
"The Rime of the Ancient Mariner"