Every lighthouse on the East Coast, flashing its real characteristic, on the real clock — a lighthouse is identified by timing, and the Light List publishes both its flash and its fog signal to the second. The eye is God's: the map shows all of them at once. The ear is a mariner's: it sits on the water and hears only what a ship there would, panned by bearing and faded by distance. Fog takes the beams away and brings the horns up.
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