This is an apparently simple image of a boat seen between rocks. Colquhoun said that the title refers to the female sea-monster who, according to the ancient legend in Homer's Odyssey, inhabited narrow straits and devoured passing sailors. However, this reference to mythology was provoked by an unexpected recognition of one form in another, as Colquhoun explained: 'It was suggested by what I could see of myself in a bath … it is thus a pictorial pun, or double-image'.