By the early nineteenth century, the field of obstetrics had emerged from the arena of general surgery as an independent area of specialization. Among the contributors to the new field, the Hungarian physician, Ignaz Semmelweis, is generally given the place of honor, because he fought valiantly, to his own detriment, to convince his colleagues that the cause of the high mortality rate among women giving birth was puerperal fever (also known as childbed fever), and because of his insistence on sterilizing the hands of those who assisted with the delivery of babies. The fact that puerperal fever is caused by infection was known to British physicians prior to Semmelweis's work: for example, the Scottish physician Alexander Gordon (1752-1799) is known to have provided empirical proof, refuting numerous popular, but utterly unscientific, theories about the disease. However, most physicians were revolted by the idea that a doctor's hands can...