A hale old Roman once gave him a little exhibition of his skill in fence, taking a clothes-peg for his mark. ‘What do you think of my play, Demonax?’ he said. ‘Excellent, so long as you have a wooden man to play with.’

Even for questions meant to be insoluble he generally had a shrewd answer at command, Some one tried to make a fool of him by asking, If I burn a hundred pounds of wood, how many pounds of smoke shall I get? ‘Weigh the ashes; the difference is all smoke.’