The DMV eye test machine

Foreheads arrive in a narrow range, high enough to clear the chin bar, low enough to meet the hood, and the machine adjusts to none of it. It waits the way a turnstile waits, indifferent to the next face that will attempt it. Inside the hood, two small circles hold separate slides, so each eye takes its own private exam without conferring with the other, a trick borrowed from stereopsis and rarely explained to the person squinting into it. The chin rest carries a faint groove worn smooth by chins it will never meet again, since almost no one returns to the same unit on purpose. A clerk asked about unusually pointed chins produces a paper towel folded twice, the county's closest approximation of an adapter. The lit window at the center of the hood holds the line that decides the appointment: read it clean and leave with a smile printed on plastic; hesitate on the middle row and leave with a referral slip instead. Forty people can fail the same letter and pass the one directly below it, which is generally taken as proof that the eye reads context as readily as shape. The machine keeps no ledger of any of this. It resets between faces, offers the same two circles to the next one, and asks the same question every time, whether or not anyone answers it well.

R. Quist