"A Song of Despair" is sung to a woman, and her old lover calls her a lot of things. She's beautiful, raging, a pit, the sea, the list goes on (really, it does… just read below). The way that the feminine is described in Neruda's poetry is controversial, some say machista (meaning essentially that he's a male chauvinist). This particular poem sees the feminine as a giant force that will swallow everything in its path. Batten down the hatches!
Line 6: One reading of this line is that the woman is a pit or a cave, something where lost and damaged things end up. This shape, the concave one, will be recurring throughout the poem and has to do with the traditional role of the female in the reproductive act—if you catch our drift.
Lines 9-10: The pit or cave is hungry! The woman is compared using metaphor to distance, the sea, and time—all of which are vast and hard to comprehend, and all of which can swallow everything up, eventually.
Line 21: The woman finally takes a human shape here, but instead of being her own person, she is part of the speaker. He can only think of her either as a force of nature or something that is his own.
Line 23-24: That concave shape is back, and this time it's a… jar. In this simile the woman is supposed to contain everything, like a jar, and she does, but it ends up shattering her. She was a fragile jar, as it turns out.
Lines 25-28: Now instead of being a destructive force, these metaphors suggest that the woman gives life. The island where she takes in the speaker is probably his loneliness, and she gives him fruit and miracles just when he needs them most. This might be an allusion to Adam and Eve, but the fruit in that story ends up being pretty problematic.
Lines 29-30: Once again that idea of containment comes up. The feminine figure in this poem is meant to take in and protect the masculine.
Lines 33-34: And we're down in the dumps again. Just like the pit, the cave, and the jar, this time the concave shape is a tomb. This line lets us know that the love is dead, but the fruits mentioned in line 27 are still present—even if they are being pecked at by birds.
Lines 43-44: Man, that pit just won't go away. The woman seems to be the place where the speaker let out all of his garbage, or baggage, or whatever you want to call it.
Lines 45-46: The woman here is kind of like a siren, luring sailors to their deaths as they sing out over the sea. She is, once again like Eve, a temptress and dangerous.
Line 47: The song is still present, and the woman is connected to the sea again in this line through the currents. The repetition of "still" lets us know that she survived the love affair, probably without much trouble, like the sea survives a shipwreck.
Line 48: The last metaphorical dig repeats the pit of debris line and this time calls the woman an open and bitter well. She's a source of water, but it's a bitter source. She can give life and nourishment, but it is painful.