Spirals: growth that keeps its shape

A fern before it opens is wound tight, the tip tucked into the middle like something being kept for later. A shell does the arithmetic more slowly: every chamber is larger than the one before it, and none of them is a different shape. That is the odd promise of a spiral — it can grow for years without becoming anything else.

Photographed close, the shape does something to the eye. It refuses to stop at the edge and walks inward instead, turn after turn, the way you follow a road you have no plan to reach the end of. With a macro lens and the aperture open, only one turn stays sharp; the center goes soft before you arrive. It feels less like a flaw than like an honest account of how looking works.

On a screen the spiral is easy company. It offers a route without a destination, sits off to one side of the icons, and never asks to be finished. A week later you notice the third turn from the middle for the first time, which is more than most images give you.