Napoleon's Haemorrhoids, By Phil Mason

The history of Europe might have turned out very differently had Napoleon not had an attack of haemorrhoids that intervened with his usual battlefield surveillance. How such seemingly tiny events can have large consequences is the subject matter of Phil Mason's entertaining book. Tiny paragraphs are organised under categories including history, politics, war, science, art, sport, crime and business.

One of the best chapters is "Artistic Strokes (of Luck)", in which we learn about Agatha Christie's chance path to writing: born to a mother who believed no child should look at a book before the age of eight, it was working in a chemist's dispensary in her mid-twenties that fuelled so many of Christie's poison-filled plots. Meanwhile, Evelyn Waugh would not have lived to write Decline and Fall had his suicide attempt by drowning, aged 21, been successful (he was deterred by a shoal of jellyfish).

Some of Mason's examples stray beyond the bounds of his own theory. But the more apposite are well worth reading.