"Oh, the sea's full." McDunn puffed his pipe nervously, blinking. He had been nervous all day and hadn't said why. "For all our engines and so-called submarines, it'll be ten thousand centuries before we set foot on the real bottom of the sunken lands, in the fairy kingdoms there, and know real terror. Think of it, it's still the year 300,000 Before Christ down under there. While we've paraded around with trumpets, lopping off each other's countries and heads, they have been living beneath the sea twelve miles deep and cold in a time as old as the beard of a comet."

"Yes, it's an old world."

"Come on. I got something special I been saving up to tell you."

We ascended the eighty steps, talking and taking our time. At the top, McDunn switched off the room lights so there'd be no reflection in the plate glass. The great eye of the light was humming, turning easily in its oiled socket. The Fog Horn was blowing steadily, once every fifteen seconds.

"Sounds like an animal, don't it?" McDunn nodded to himself. "A big lonely animal crying in the night. Sitting here on the edge of ten billion years calling out to the Deeps, I'm here, I'm here, I'm here. And the Deeps do answer, yes, they do. You been here now for three months, Johnny, so I better prepare you. About this time of year," he said, studying the murk and fog, "something comes to visit the lighthouse."

"The swarms of fish like you said?"

"No, this is something else. I've put off telling you because you might think I'm daft. But tonight's the latest I can put it off, for if my calendar's marked right from last year, tonight's the night it comes. I won't go into detail, you'll have to see it yourself. Just sit down there. If you want, tomorrow you can pack your duffel and take the motorboat in to land and get your car parked there at the dinghy pier on the cape and drive on back to some little inland town and keep your lights burning nights, I won't question or blame you. It's happened three years now, and this is the only time anyone's been here with me to verify it. You wait and watch."

Half an hour passed with only a few whispers between us. When we grew tired waiting, McDunn began describing some of his ideas to me. He had some theories about the Fog Horn itself.

"One day many years ago a man walked along and stood in the sound of the ocean on a cold sunless shore and said, 'We need a voice to call across the water, to warn ships; I'll make one. I'll make a voice like all of time and all of the fog that ever was; I'll make a voice that is like an empty bed beside you all night long, and like an empty house when you open the door, and like trees in autumn with no leaves. A sound like the birds flying south, crying, and a sound like November wind and the sea on the hard, cold shore. I'll make a sound that's so alone that no one can miss it, that whoever hears it will weep in their souls, and hearths will seem warmer, and being inside will seem better to all who hear it in the distant towns. I'll make me a sound and an apparatus and they'll call it a Fog Horn and whoever bears it will know the sadness of eternity and the briefness of life.'"