The Swan Brewery, Mortlake

By fluke, the shadow of the chimney in the foreground is falling directly onto the shorter one behind, which just has its top few courses up into the morning sunlight.

Ignore this first comment - looked again this morning, the angles are all wrong - it is just that the chimney in the background is nearly all dark brick except at the very top where it is light-coloured. What an eeejit.