The Universe
Metaphorical imagery is used to describe the universe. "Think of the universe like a spring. You normally travel on the edge of it, along the loop of the coil." The significant aspect of this simile is the coiled construction of a spring. Spring always has a hole in the middle of the coil. This comparison is essential because at the center of the story is an invention referred to only as the machine.
The Machine
The machine is a complete mystery for most of the story. Later it will become slightly less vague. "The machine is like a big screw. It’s going to spin around and shoot right up through the middle." This simile explains the significance of the previous one. It turns out the machine is some sort of device capable of threading that hole in the spring that is the universe.
What is Life
The question of what life is gets answered simply and efficiently using metaphorical language." Life is a path, Martin, and you follow it. Sometimes you follow it blindly. Maps are for doubters, and I raised a believer.” This is fatherly advice to a son. The advice comes from a father who, somewhat ironically, staked out a destination for himself and his son on a mostly isolated island from which they never leave to explore any other existence. As with most of his advice, it is ambiguous but taken as great wisdom by the boy.
Ferris Wheel
An amusement park leads to an encounter with a Ferris Wheel. "It rose through the trees like the skeleton of a giant flower." This simile refers to the immediate familiarity of a visual encounter with this ride. The open construction is actually very much like a skeleton. The specific choice of a flower seems to refer to the seats which may resemble flower buds from a distance.
Cars
The father has tried to keep his son shielded from the dark side of modernity. As a result, his first encounter with a car is recognizable to him only because of the metaphorical imagery with which his father had described automobiles. Cars were simply “boats with wheels and windshield wipers." The comparison of things he does not know with things he does know allows the son to come into the modern world off the island without being completely overwhelmed. A car may not really look much like a boat with wheels, but the simile makes sense to a ten-year-old.
