I can’t see any coastline. In the direction from which I’ve come the sky is blue and benign, but behind me the darkness is gathering into towering mountains of cloud. There are claps of thunder and the longer I look, the more certain I become that something is splintering the water over there.

There! I shade my eyes. Yes, over there! Invisible cliffs, against which the waves pound and crash, falling back as milky froth, subsiding, and being thrust against the bottom and the rocks and an invisible barrier. The sea’s roaring. A never-ending line of cliffs, a wall of glass, and inside it . . . Fog?

I sit down on the rowing bench. I must rescue the girl, I think, but when I peer at the whale rock where the child was sitting a second ago, the girl is gone.

I feel the current straining at the blue boat’s bows. The tide is turning. It’s going out. The roaring grows louder, as if the sea has been transformed into a gigantic waterfall, cascading thousands and thousands of feet into a thundering, black chasm.

I turn round in the blue boat. The waves loom like mountains, houses upon houses high, grinding, bursting, and shattering against the barrier. I can now see that it is a sort of pipe that is smashing the waves. Not a glass pipe, but one filled with fog and night. My fear tastes of blood.

In winter the coast of the Iroise Sea suggested that the heavy, gray-blue, rolling sea was bent on taking a running start, leaping onto the land, and advancing over the waves of grassy hummocks to drag people from their beds. The waves hurl themselves against this tube of darkness and scudding shreds of fog every bit as brutally. I almost believe that I can see stars being sucked through it, treetops and mountain peaks and the shadows of cities appearing from it now and then, but so briefly that I can’t be sure if I’m seeing properly. The pipe stretches out left and right to the landless horizon. All along it, waves hurl themselves against this barrier and bounce back in a mass of seething foam. The sky has also peeled back, yellow as pus, gray as smoke, and toxic.

The boat rises and falls, listing dangerously low on both sides. Spray flies over the gunwales.