In Chapter 1, when the cyclone picks up Dorothy's house, Baum uses a simile that foreshadows Dorothy's later attempt to get back to Kansas with the Wizard of Oz:
When she was halfway across the room there came a great shriek from the wind, and the house shook so hard that she lost her footing and sat down suddenly upon the floor.
A strange thing then happened. The house whirled around two or three times and rose slowly through the air. Dorothy felt as if she were going up in a balloon.
Baum compares the feeling of being "whirled" about by the cyclone to the feeling of "going up in a balloon." In Chapter 17, Dorothy almost gets the chance to literally go up in a balloon when the Wizard of Oz tells her that he can try to bring her back to Kansas in the balloon that first brought him to Oz. They will use hot air to lift the balloon; just as air currents blew Dorothy and the Wizard from the American Midwest to the strange land in which they are stranded, the Wizard hopes that the same air currents might blow them back home. This plan sounds reasonable to Dorothy. But at the last minute, she must go after Toto and misses the balloon launch. Just as rescuing Toto kept Dorothy from reaching the storm cellar in time to avoid the cyclone, rescuing him again prevents her from escaping Oz in a balloon.
The failure of the balloon plan is disappointing at first, but it gives Dorothy the chance to realize that she is not as subject to the way the wind blows as she thought. She takes charge of her own fate, searching out Glinda for help getting home. Glinda tells her that she has always had the means to get home, simply by clapping together the heels of the Silver Slippers. Like the other characters who have been looking outside themselves for what they need, Dorothy too learns that she already has everything she needs. The cyclone is the ultimate outside force acting upon her. By comparing the experience of being inside the cyclone to the experience of "going up in a balloon," Baum emphasizes Oz's balloon, too, as an outside force that is ultimately not the solution to Dorothy's problems.
In Chapter 12, the narrator uses a simile to describe the Wicked Witch's power to see across vast distances:
Now the Wicked Witch of the West had but one eye, yet that was as powerful as a telescope, and could see everywhere. So, as she sat in the door of her castle, she happened to look around and saw Dorothy lying asleep, with her friends all about her. They were a long distance off, but the Wicked Witch was angry to find them in her country; so she blew upon a silver whistle that hung around her neck.
The Wicked Witch's eye is as powerful as a telescope. It is not so much a human feature as a piece of technology that allows her to surveil her entire kingdom from her position at the center of it, in her castle. Without moving, she can blow a whistle to raise the alert. The people she forces to work for her know that they are supposed to go arrest Dorothy and her friends, bringing them into custody and under the Wicked Witch's control.
Although, again, Baum insisted that his book was not a political allegory or commentary, there are clear parallels between the Wicked Witch's telescopic eye and the idea of the panopticon, a model for prisons first proposed by Jeremy Bentham in the 18th century. The panopticon placed a guard in a tall tower at the center of a prison with a one-way line of sight onto each inmate. The ability to surveil everyone at once was supposed to give the guard a high level of control over the entire facility. Versions of this model for prisons were popular throughout the 19th century and into the 20th. The model was also adapted for factories, schools, and other institutions where management sought a high level of control.
There are many other elements in the book suggestive of the way corporations exploit their workers. No matter what Baum intended, it is possible to read the book in part as a condemnation of American corporate greed at the end of the 19th century. With this interpretation in mind, the Witch's telescopic eye represents the evil, dehumanizing force of corporate surveillance and control. Given the way Baum also describes the Wicked Witch as an enslaver who uses violence and surveillance to control the people she enslaves, her resemblance to a corporate manager further evokes some parallels between the tactics used by American chattel enslavers and the tactics used by corporations to control their workforce. While it is important to distinguish between unfair labor practices more broadly and the race-based system of enslavement that flourished in the United States for centuries, the book suggests that both rely on dehumanization, violence, and the intense supervision of workers' lives.
