Hal on advertising and the fall of the Networks (pp. 412–413)
The ads with the more dental-pain-type paintings Hal doesn’t even want to think back on, what with a fragment of cannoli wedged someplace upper-left he keeps looking around for Schacht to ask him to have an angle-mirrored look at.
Context
The screen's mirror hit for the scene: the only mirror in Hal's whole advertising excursus is a dental angle-mirror, wanted in the present-tense frame (the wedged cannoli fragment, the incipient carie) while the essay material unspools in memory. A mirror for seeing into one's own mouth — inspection optics on the viewer's own body, deployed in the same breath as ads whose whole mechanism (below) is making viewers unable to bear what they're shown. Small, but it's the frame-story's one optical instrument.