Depth Gauge, Obsolete Competition Tank

The painted depth numerals run floor-to-wall at the deep end — 1.8, 2.0, 2.5 — each figure cracked and tide-stained, the zero of the lowest mark half-eaten by efflorescence. I set up at close range so the numbers fill the frame diagonally, the concrete's mineral biography pressing right up against the lens. What interested me was how a measurement system designed entirely for a liquid medium survives, still legible, in pure dryness.