The mosaic is a motif from the Odyssey (song IX). Ulysses and his men are trapped in the cave of the cyclops Polyphemus who have been eating some of Ulysses' men, two for breakfast and two for diner. Ulysses tricks Polyphemus into drinking strong wine so he falls asleep. While sleeping Ulysses and his men blind Polyphemus with a wooden pole they have pointed in the fire."
