Symbolism, Imagery, Allegory
Yup: the Chicago World's Fair didn't just introduce to the world to newfangled inventions like the zipper and the lightbulb—it also gave the world its first spin on a Ferris Wheel.
But George Washington Gale Ferris' "monstrosity" isn't well received at first. After all, he does propose to launch two thousand passengers through the air at once, which: yikes. However, Burnham wants something to out-Eiffel Eiffel's Tower from the 1889 Paris Exposition. And Ferris was one of the few to rise to the challenge, showing America that he has the ingenuity and prowess to do what has never been done before.
Though it opens weeks after the fair gets underway, the Ferris Wheel becomes the fair's emblem in no time at all.
[It's] a machine so huge and terrifying that it instantly eclipsed the tower of Alexandre Eiffel that had so wounded America's pride. (Prologue.8)
With the Ferris Wheel, America is back on top again. Literally: the one at the World's Fair was taller than the Statue of Liberty, and broke all sorts of records.