In spite of this, Wills strengths lie in his descriptions of how the plague bacillus was discovered and became to be understood during the late nineteenth and early twentieth centuries. Overall then, the chapter provides an interesting account of nineteenth-century biological science coupled with some historical background. Although the evidence is difficult to interpret, Wills concludes that The outbreaks in Beed and Surat may not have been plague after all. While this chapter provides a useful summary of the available evidence, interspersed with accounts of his visit to India and the appalling levels of poverty that can be found in parts of that country, it is difficult to see how such a comparison adds much to his general thesis about the nature of plagues. It does tell us much about popular perceptions of plagues, but that is another matter.
Similar problems arise in some of the other sections.
Chapter 6 compares the impact of cholera in nineteenth-century English cities with recent outbreaks in Peru. Wills describes the classic piece of epidemiological detective work by John Snow who discovered that cholera could be linked to an infected water supply in the famous Broad Street Pump. Curiously though, one of the most important pieces in the jigsaw that enabled Snow to link cholera to the pump, the widow who each day had a bottle of water fetched from the pump to her house in Hampstead and consequently became the only person in that area to die during this outbreak, is missing from the story. The discussion of choleras epidemiology is once again interesting, but it is sometimes difficult to see the parallels between nineteenth century London and modern-day Peru where poverty, poor sanitation and inadequate medical facilities combine to ensure that cholera still remains a threat. In the introduction we are led to believe that some an important global theory about how plagues can be understood is to be presented, but as the book enfolds this promise is not quite fulfilled.