Frater, ave atque vale
As his obituaries pointed out, my brother David made a name for himself with his unrideable bicycle; his ‘perpetual motion’ machine — a bicycle wheel still rotating in a frame on our mantelpiece (it attracted 1.1 million hits on a German website); and his theory that the arsenic found in Napoleon’s hair and fingernails was down to his wallpaper. The papers naturally got all this wrong (‘Napoleon killed by wallpaper’ they intoned, as did Andrew Roberts), and the image of the potty prof emerged. In fact, his purpose was serious. He was equally serious about our children — after a failed marriage, he had none of his own, to his