Cows in a soggy meadow by Willem Maris

Willem Maris painted 'Cows in a Soggy Meadow' around 1860, and the real subject is not the cattle, it is the Dutch light dissolving into wet ground. The painting belongs to the Hague School, a group of 19th-century Dutch artists who turned away from romanticized studio landscapes to paint the flat, damp polder country as they actually saw it.

The magic is in what Maris leaves out. A broad shallow pool in the foreground holds a faint reflection of the cattle, rendered in just three or four broken horizontal marks. The wet ground texture is a virtuoso passage of short, variegated strokes: crushed grass, saturated soil, and standing water suggested without a single hard edge. Your eye assembles the soggy meadow from raw paint.

Maris was the youngest of three painting brothers. His older sibling Jacob was famous for precise Dutch townscapes, but Willem went the other way. He worked en plein air when that was still unusual, scrubbing colour directly onto the canvas to catch the humid atmosphere before it shifted. He famously said he didn't paint cows, he painted light. The brown cow at centre is a case study: warm russet impasto against a pale grey sky, the hide built from tactile dabs of the brush rather than drawn outlines.

Look up into that enormous sky and you'll spot three or four tiny brush-flick birds. They are almost nothing, just dark strokes against luminous grey, but they animate the whole vast stillness above the plain. How many marks do you count that actually make the cow's body?