There is about the swimmer a sentimentality, or self-pity, which disgusts him even as he finds himself thinking that surely he ought to have earned a reprieve. All that close attentiveness to the sea over the years, to this ever-yielding, stony-hearted medium which has him in it embrace - it cannot have been wasted. there must be something he has learned from it, some subliminal message from his ancestral home, instructions for survival. The idea is fatuous but persistent.
He is beginning to tire. Not of staying afloat, since this is effortless, but of trudging the water to stand higher, of spinning to keep every horizon constantly in view. More and more he allows his face to hang in the water. Through the glass panel of his mask his vision lengthens past the rope's end twenty feet below his ankle. He no longer sees the prismatic chips of phytoplankton, the blazing motes and jellies as they drift past his face. Now he believes he glimpses shapes far beneath, not predators but bulks of deeper purple as though . . .Why not? This archipelago is full of hidden reefs, its contorted seabed thrusts up unexpected pinnacles to within feet of the surface in the middle of nowhere. There could easily be a coralline peak, a ledge, even a plateau over in that direction away from the sun where the water does seem to deepen its color as if a little farther down there lay a solidity. . . .
Away from the sun? The swimmer jerks his head up, gasping and squinting painfully at the blazing disc overhead Is it not past its zenith now? Has it not begun to sink? May this illusion of a darker bulk be nothing but his own shadow, cast as he has so often seen it in late afternoon? No; ridiculous. It is not late afternoon, merely maybe a few minutes past midday. He looks downward again and in a while his eyes adjust from the dazzle and once more he thinks he can pick out an area of deeper tone. So convinced is he that he begins swimming toward it, slowly, so as not to give the impression of having finally picked a direction or of expecting very much. Now and again he glances around to tell his invisible boat where he is going. It seems to him that all will be well if it turns out to be a lonely reef he is heading for. However small, it will convert the ocean at that point into a shallow sea. He would then, as if by magic, be in his depth in twenty feet of water. Or at least, hovering as if in air above the unknown but familiar city, he would be close enough to feel its dwellers might intercede for him, present his case for survival as some court of marine jurisprudence. . . . As an idea it is better than nothing; even a glimpse of a reef would sustain him. Besides, reefs were mysterious and deceptive places whose greater being remained hidden. If one kept one's eyes on a reef under water and followed its avenues, it had a habit of turning into a shore. The swimmer had experienced it a thousand times. Might not this one, despite an apparently yawning horizon, somehow work the same friendly trick?
-Seven-Tenths: Sea and Its Thresholds, James Hamilton-Paterson