Bart approaches Dr. S, the owner of the Spirograph Factory. He is hunched over a drafting table, lit by the beam of a single angle lamp, and holds a pen and several plastic Spirograph wheels over a piece of paper. The wheels have interlocking gears which allows one to rotate against others. When a pen is inserted into one of many holes in the wheels, they can be used to draw intricate repeating patterns with complex rotational symmetry. Dr. S looks over his shoulder at Bart, with an intense, perhaps anguished expression. Behind him is a large corkboard with dozens of finished Spirograph drawings pinned to it.
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