ALEXANDER FLEMING FIRST made his name by treating syphilis. The most effective method of the day involved injecting the patient with 600cc (over half a litre) of solution through a hypodermic needle the size of whcih would, nowadays, preclude it from use in anything other than veterinary medicine. The quantity of liquid injected was so great that if it was improperly administered the patient's arm would have to be amputated. The dextrous Scot's skillful use of the unwieldy equipment earned him a reputation as a clinician, but, Eric Lax explains in this satisfying history, it was research that really appealed to him.

Fleming's studies took him, in 1914, to the Western Front and a field laboratory near Boulogne. The Great War was a dirty one, in which half of the men who died were killed by infections. The bacteria that caused these were fostered by the fertilisers ploughed into the fields in