Darl describes the road as a spoke of a wheel, and the wagon, with Addie on it, as the rim of the wheel. Can someone explain this metaphor?

Faulkner's metaphorical languagemirrors the circularity of his journey narrative, describing how the "road vanishes beneaththe wagon as though it were a ribbon and the front axle were a spool" (39). The windingand unwinding of the road under the wagon denies any teleological finish. The narrativeis devoid of any meaningful conclusion but instead its repetitive structure is like a turningwheel, and "the red road lies like a spoke of which Addie Bundren is the rim" (108).Addie constructs the shape of the journey but she does not give it purpose. Thetraditional figurative language that accompanies a journey narrative, building a semanticnetwork of understanding and meaning, is lost in Faulkner's text.