How does Achebe maintain the tone of the chapter and the sgnificance of Chielo's power when the priestess reaches the circular ring of hills? How might a western reader interpret this section?

The priestess of Agbala is a mysterious and frightening figure. Remember that in normal life she is Chielo, a widow who is slight and getting on in years. Yet even with a large child on her back, as the Oracle she moves at an astonishing rate. And the relationship between Chielo and Ekwefi also seems important here. The Oracle's interest in Ezinma turns out to be benevolent. Remember that Chielo is a friend of Ekwefi, and the old widow is also particularly fond of Ezinma. Given Ezinma's health troubles, we can infer that the priestess is seeking some kind of spiritual protection for the child. And indeed, in later chapters we learn that Ezinma ceases to be a sickly child after this strange night with the Oracle. The tone of the chapter is full of the intense mystery not understood by Western culture. I think, through the lens of "civilization", this chapter seems the stuff of tribal mythology yet the author infuses it with a certain intensity that makes it almost believable.