A Reminder of Escher's "Still Life and Street" (1937)
I thought you were setting the alarm when an ambulance seemed to magnify what was, after all, the crossing signal. Table and street were on one surface.
The poem catches a small moment of confusion. The speaker hears a noise and assumes someone nearby is setting an alarm. Then an ambulance siren seems to swell, and the sound turns out to be, "after all," the crossing signal.
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