I don’t think I ever once saw his hands clean. As Mrs Brooker was now an invalid he prepared most of the food, and like all people with permanently dirty hands he had a peculiarly intimate, lingering manner of handling things. If he gave you a slice of bread-and-butter there was always a black thumb-print on it.

- from Orwell’s The Road to Wigan Pier

This passage caught me so completely by surprise that I emitted something between a chuckle and a sputter. The only witness to this, thankfully, was a deaf spaniel. If he heard me, he was gracious enough not to say anything.