Slavery, and the real significance of Machado's Dom Casmurro

J. Machado's novel Dom Casmurro (1900 - btw I'm not so sure about the translation of the title, the narrator's moniker, and I was wrong in earlier posts to call him a "writer" - his career was as a lawyer, but he's writing this novel as a personal memoir) is a terrific book start to finish - full of surprises that are credible and rather than forced and gratuitous, guided by a witty and largely self-aware narrator, and presented as a series of about 150 short chapters, each w/ a title; this unusual structure gives us plenty of "breathing room," places to pause easily and reflect on the developing plot, and makes it especially easy to follow the story line. The story line is, in essence, the life story of the narrator, Benhinto, who at the outset, the 1890s, is a successful Brazilian businessman, who tells us his life story - his struggle against his mother's vow that he would enter the seminary and become a priest, his love for his beautiful next-door neighbor, Capitu, and their attempt to build a life together. The story is exceptionally sad, though w/ moments of great humor, and in telling the story - stretching back to the 1850s, Machado presents the life of an entire family - much like, say Buddenbrooks or Confessions of Zeno or The Leopard, great company! - and informs us about a way of life - among the professional classes of Rio in the mid-19th century that, even by the end of Machado's life, seemed long gone. Recent news stories have reported that research has shown that Machado was in part of African descent. That's really significant, as one of the elements of the novel is the casual acceptance of slaves in the family (not outlawed in Brazil till the 1870s); at first, the slaves play just a minor role, doing various tasks for the household, but toward the end the narrator gets into a discussion about his family wealth, which they measure not only by property owned but by the # of slaves kept. That unremarked acceptance of slavery becomes even more strange in that it's part of a story line that is about freedom from parental bonds, about fidelity to oaths and promises, and, in particular toward the end, about lineage - so we can see why Machado was drawn to this theme yet he kept the issue of slavery in the background of the story, like an unrepented sin.