And bright ships have left you this or that in fee: (3)
In the first line the speaker describes the woman as the Sargasso Sea, so we know he is continuing that metaphor into this line. "Bright ships" can't be taken literally here; they must be metaphors for something else. (Otherwise, how can ships visit her in the middle of London, and why would ships need to leave her a fee?) Further down in the poem, the speaker states that "great minds" seek the woman out, so maybe the ships stand in for them. Any ideas about why the ships are described as "bright"?
Ideas, old gossip, oddments of things, Strange spars of knowledge and dimmed wares of price. (4-5)
These lines list what the "bright ships" pay as a fee to the woman, but almost all of these things are described as being fairly worthless. In contrast to the brightness of the ships, everything in this list is old, odd, strange or dimmed – it's a lot of random rubbish that we wouldn't know what to do with.
And now you pay one. Yes, you richly pay. You are a person of some interest, one comes to you And takes strange gain away: (13-15)
So we know that the "bright ships" leave the woman a fee, and now we know that she pays something too. But what is everyone paying for? What is being purchased? The word "interest" here is also, well, interesting, because it has a double meaning. "Interest" is what we feel when we are intrigued or curious about something, but it can also refer to a fee that accumulates on top of loans. This could be an explanation for the "strange gain" a person gets from interacting with the woman.
Idols and ambergris and rare inlays, These are your riches, your great store; (23-24)
In these lines the woman certainly sounds pretty wealthy. Idols, ambergris, and rare inlays are pricey things, and the speaker describes the woman as having a "great store." "Store" here probably doesn't mean a place you go to buy things, but rather one's own storage or supply of things. Of course, just a few lines down, the speaker is going to flip back on us and tell us that these riches don't really belong to the woman at all.
For all this sea-hoard of deciduous things, Strange woods half sodden, and new brighter stuff: (25-26)
Again, this vague word "strange." An interesting essay topic might be to determine what exactly "strange" is supposed to mean in this poem. Here we start to think that maybe this lady isn't so rich after all. She has a "sea-hoard" of things, which we take to mean "a huge amount," but these things are "deciduous" and "half sodden." Breaking apart and soggy? Ick. We're slightly optimistic about the "new brighter stuff," but what exactly is that? Why does the speaker have to be so vague here?
In the slow float of differing light and deep, No! there is nothing! In the whole and all, Nothing that's quite your own. (27-29)
It turns out that the speaker brings up the "new brighter stuff" just to tell us here that, among both the old and new things, the woman doesn't really own any of it. What do you make of the phrase "In the slow float of differing light and deep"? Is the speaker still using sea imagery, has he returned to the city and the lady's immediate surroundings, or is he being deliberately ambiguous?
The structure of this phrase parallels "In the whole and all," so we could read it as meaning the same. In fact, "differing light and deep" is a nice way of saying "whole and all," because "light and deep" recalls two pairs of opposites: light and dark, and high and deep. Notice how "light" and "high" have similar sounds, as do "dark" and "deep." Therefore, the single phrase, "light and deep," manages to recall and encompass an enormous range of meaning.