How we cite our quotes: (Line)
Quote #1
Your mind and you are our Sargasso Sea,
London has swept about you this score years
And bright ships have left you this or that in fee: (1-3)
Just over the first line break, the poem jumps from the Sargasso Sea to London. Interestingly, London retains some of the sea's characteristics: it "sweeps" about the woman, bringing "bright ships" to her. The speaker says the woman herself is the Sargasso Sea, but this appears to give her urban surroundings a marine quality as well.
Quote #2
Oh, you are patient, I have seen you sit
Hours, where something might have floated up. (11-12)
The woman is described like a fisherman here, patiently waiting with her line in the water in the hopes something will bite. This contrasts strikingly with what's probably her actual situation: sitting in a London living room or salon, hoping some interesting idea or story arises from her conversations and interactions.
Quote #3
Trophies fished up; some curious suggestion;
Fact that leads nowhere; and a tale or two,
Pregnant with mandrakes, […] (16-18)
Civilized conversation (the kind of conversation two genteel people hanging around London would have) is given very natural and physical qualities here. It can be "fished up" or even "pregnant with mandrakes." Even when the speaker describes a "fact that leads nowhere," we picture a small guppy with "Fact" written on him, swimmingly frantically away from a fishing line.