How does Harper Lee control the rise and fall of intensity in Chapter 6 of To Kill a Mockingbird?

This is
one of the most interesting chapters in the novel, and authortakes her reader on a wild ride
full of childish curiosity, intrigue, danger, innocently off-color humor and a near sighting of
--all in one night. It is Dill's last evening in Maycomb for the summer, andand Dill are
pretending how to spend it, though they have already decided that a raid on the Radley's back
porch is in order.suggests that they "watch for Mr. Avery," and Lee launches into a
story about the children previously witnessing an extraordinary event:

... an arc of yellow water descending from the leaves and splashing
in the yellow circle of the street light, some ten feet from source to earth... 
()

It...