What metaphors are used in The Known World by Edward P. Jones?

The novel offers a metaphor for itself in the last chapter, when Henry Townsend's brother-in-law, Calvin Newman, stays in a hotel in Washington, D.C., where he sees a work of art created by fugitive slave Alice Night: "a grand piece of art that is part tapestry, part painting, and part clay structure … [It is] a kind of map of life of the County of Manchester, Virginia."