What are some examples of imagery in The Catcher in the Rye? (especially relating to challenge and change)

Near the end of the novel, Holden goes to visit Phoebe,
and he takes her to Central Park.  There he watches while she rides the carousel.  The
horses of the carousel are described as looking wild with their mouths open as they go
around the circle.  Phoebe, however, is not afraid and she chooses a horse to ride. 
Holden thinks that this image suggests children taking risks and thus learning through
experience.  So, the imagery in this scene complicates the typical sense of innocence
that surrounds children's carousels and merry-go-rounds--the element of experience is
present.  Through this image of Phoebe taking on a risk, Holden's views about the
disillusionment of adulthood are challenged.