“When, dreadful to behold, from sea we spied
Two serpents, rank’d abreast, the seas divide,
And smoothly sweep along the swelling tide.
Their flaming crests above the waves they show;
Their bellies seem to burn the seas below;
Their speckled tails advance to steer their course,
And on the sounding shore the flying billows force.
And now the strand, and now the plain they held;
Their ardent eyes with bloody streaks were fill’d;
Their nimble tongues they brandish’d as they came,
And lick’d their hissing jaws, that sputter’d flame.”

(Vergil, The Aeneid, book II, lines 269–271, trans. John Dryden.)