In that dim cavern was so little light, -- Yea, well-nigh might be said that light was none-- Nought sees or comprehends the English knight What wavers so, above that vapour dun:
For surer proof, a stroke or two would smite With his good faulchion Otho's valiant son:
Then deemed that duke it was a spirit, whom He seemed to strike amid the misty gloom.