When it shows up in the poem, the ocean is a gloomy, mysterious and far-away place. Nothing in particular happens there, except that it marks the end of the river. It's a dead-end, a place where there is no life or light. The other settings in the poem tend to be active and alive. The forest is sunny, the river is noisy, the dome is warm, even the caves are deep and icy. The ocean, however is just an empty, open space. It might make us think a little bit of the Underworld, a place where things simply end.
- Line 5: Our first image of the ocean emphasizes the absence of light. It's a place where no sun shines, far away from the "sunny spots" we will see in line 11. The alliteration of the two "s" sounds also adds to the sense of mystery and emptiness, and gives this short line a slithery, sinister, sound.
- Line 28: Here it is the absence of life that becomes the most important part of this image of the ocean.
- Line 32: In this line, the ocean is a blank canvas. The shadow of the palace floats on it, but we don't have any sense that it has a life of its own.