catapult magazine

Zooming out

by James Stewart

In 1854 the Soho district of London—now home to much of the city's alternative culture and numerous expensive ad agencies but then a dirty, smelly neighborhood full of (mostly poor) recent immigrants to the capital—suffered one of the most severe cholera outbreaks in the city's history. From the agonized suffering of one baby the virus swept through the district taking the lives of hundreds. It also provided the evidence needed to overturn established understandings of disease.

In the 1850s the prevailing theory of the spread of disease was known as the "miasmatic" theory. Having seen dreadful disease emerging from the slums that had grown after the Industrial Revolution, the medical profession had decided that the awful smell of those slums must be the cause of the disease and so public health programs were largely driven by a sense that all the human and animal waste that accumulated around peoples' homes should be cleared out. Not in itself a bad idea but, when it led to vast quantities of such waste ending up in the city's water supply, a tragically short-sighted one.

Steven Johnson's book The Ghost Map operates as something of a mystery novel, following the paths of anesthesiologist John Snow and local curate Henry Whitehead whose detailed local knowledge, active curiosity and use of creative mapping techniques led them to determine the source of the epidemic and eventually put a stop to its spread. Along the way Johnson draws us into the life of the neighborhood. Following Whitehead on his rounds visiting local families there's a very real sense of what it was like to live in Soho at the time. The stories of how families choose to use a given well for their water and the conditions in their homes are not only vital aspects of how the disease spread but draw us into their lives. Reading the book while away from London I was quickly craving a chance to re-walk Soho's streets and perhaps have a drink at the local pub (since renamed "The John Snow").

By focusing on these two characters Johnson provides an accessible route into the history, but his ideas expand well beyond their simple context. In a fashion that one reviewer described as a "Long Zoom" Johnson tells his stories on many levels, exploring the nature of the virus, family relationships and dense neighborhoods up to the workings of major metropolises. His thesis is that epidemics like that in 1854 Soho can be seen as the growing pains of a city. Any significant shift in the way humans live and interact is going to be hard and have costs, but time and again our pooled ingenuity has found ways to meet the challenges of new contexts and scales.

Johnson concludes his book by looking at the growing pains we face as our society and our cities step up to a new scale. 150 years on from a time when a city of over a million was a novelty, we're now looking at having several cities twenty times that size. The Western World may have conquered diseases like cholera, but we've yet to share out that progress, and we now face the challenges of new diseases like avian flu, the possibility that the tools of bio-terrorism will be in anyone's hands within the next few decades, and of course the immense threat of climate change.

There's the possibility that the book could have concluded with something comforting about those problems. The 19th century population of London overcame cholera, and so too we can overcome the challenges of our day. But Johnson is more sober than that. These are immense challenges on a far bigger scale than any previously imagined, and the ending of the Soho cholera outbreak rested on the fact that these two individuals were able to see through the miasmatic cloud, met each other and were able to uncover a visual device that enabled them to persuade others of their discovery. As the climate crisis deepens and the other challenges remain the example of Snow and Whitehead employing a "long zoom" and pooling their knowledge is one we'd do well to remember.