When doing a portrait, he contrived a pose that suited his view; if hands diverted attention from face, he would magisterially scumble them over, obliterating the knuckles .
In painting The Birth of the World, 1925, he started with the background, a scumble of brush strokes and hesitations.
Bacon has a trick of veiling faces with a wispy scumble of paint that creates an illusion of motion, like a photograph in which the subject moved his head.