Despite Cather's progressive attitudes towards women, marriage, and religion, she does not have the most enlightened attitude towards African-Americans. In this chapter her depiction of Blind d'Arnault makes him into an exotic, primitive spectacle. I actually think there is some shock value here.
Blind d'Arnault's piano-playing is described in highly sexualized terms. It is analogous to the act of copulation, with Blind d'Arnault characterized as being aggressive, with animal instincts and desires. Such a description conforms to negative stereotypes of the African-American male as hypersexual and driven by lustful passions, never by intellect or emotion.