This is a complex symbolic image that refers back and forwards to other passages in the novel to build its meaning. The image of the iron bar reinforces Mrs Gould's notion of the island as a "prison" , but here the prison is extended to the whole world. The "cavern" also reminds us of the "cavern-like" Customs House , which Conrad used metaphorically to portray a fundamental reality of violence and death , so if the world is this cavern, then it is a "sombre" world indeed. In such a world, the People have no choice but to fight for their ambitions: to make "conquests" by taking what they want and hiding it.

However, the phrase "conquests of love and wealth" has a larger significance because it closely echoes the very last phrase of the novel, with the crucial difference that "wealth" will become "treasure." Recalling Antonia's key distinction between wealth and treasure earlier , the implication is that Nostromo will come to reject the false treasure (wealth). And we are strategically placed right at the beginning of the change: his declaration of love for Giselle.