The Ghost Map

Categories: History , Science , Staff Picks , Nonfiction

Steven Johnson’s The Ghost Map is a few years old now, but considering the recent swine flu outbreak, it’s timely.

In the mid-nineteenth century, London was a city of more than 2 million people with an infrastructure cobbled together in less urban centuries. The number of Victorian terms for occupations related to garbage picking gives a clue to how inadequate waste management was in the city, as should the incident known as the "Great Stink," brought on by a heat wave over the polluted Thames.

In the summer of 1854, in this densely populated, filthy city, a cholera epidemic began to sweep through the crowded neighborhood of Golden Square, Soho. Medical theory held that it was spread by smell, so measures were taken to deal with that. Of course, that had little effect on the propagation of the deadly disease.

Johnson sees that summer as a make-or-break moment in the history of cities, a time when the entire urban experiment in the history of humanity could have fallen through. But the persistence of a medical doctor, John Snow, and a neighborhood curate, Henry Whitehead, traced the epidemic to a single contaminated water pump, and they finally persuaded authorities to shut it down.

The story has traditionally been told as the heroic tale of a crusading scientist taking on the establishment to forward the advance of modern medicine. But Johnson is interested in a much larger picture. Why in the face of evidence did so many scientists persist in believing traditional (and completely mistaken) medical theory? What made Snow different enough that he could see past them? How did the role of a skeptical amateur sociologist with local knowledge prove critical? How did the disaster eventually lead to changes in city management that allowed for the rise of later centuries’ megacities? And what does it have to do with how twenty-first century scientists reacted to bird flu?

It’s fascinating stuff. Johnson calls Snow a "consilient" thinker, one able to reason across multiple disciplines and make inductions on widely divergent scales. It’s a term that seems to fit Johnson himself. Any city dweller (or any reader who remembers Dickens’ novels about the dwellers among London’s euphemistically named "dustheaps") will be intrigued.