The tide came in the way it always did on that coast — not as a wave but as a rumour, a darkening of the sand that reached the sea wall before anyone thought to move the deckchairs. It is the kind of thing you only notice once, and then never stop noticing.

What follows is an attempt to hold that noticing still for long enough to look at it. There are, as it turns out, better reasons than nostalgia to pay attention to the edges of things.

A question of margins

Every discipline has its coastline: the ragged border where the tidy interior gives way to something older and less governable. Cartographers know it. So do editors.

We mistake the map for a promise. It is only ever a rumour of the ground.

The remainder of this piece walks that border, slowly, and reports back.