The Ghost Map: The Story of London’s Most Terrifying Epidemic — and How It Changed Science, Cities, and the Modern World by Steven Johnson (2006)

If you look closely, you can see the map as the border on the front cover. (Photo credit: Wikipedia)

You wouldn’t think a book about a cholera outbreak in 1850s London would be very interesting, but this one certainly was. The narrative describes Dr. John Snow, an anaesthesiologist and researcher, and the Reverend Henry Whitehead, the local cleric, over the course of a week as they investigate the vicious outbreak that hits their city.

Working with what they knew at the time — which, in 1854, wasn’t much — they had to pull so much information together to make any sense of the cholera outbreak: how and where waste is disposed, where residents get their water, who had died (and where and when and how it had happened), did the terrible smell in the air have anything to do with it? At that time, the prevailing thought was that cholera was an air-borne disease, and it mainly affected the poorest and dirtiest members of society. Snow and Whitehead had to do a lot of work to find out where the cholera had come from and how it worked, in order to try to save the Golden Square neighbourhood where the outbreak took place.

The level of detail is phenomenal. Johnson has assembled so many bits and pieces to create this book, and each bit is interesting on its own. Some of these 150-year-old anecdotes are worth the price of admission.

Johnson describes Snow in particular as being a “consillient” thinker — that is, he took what he knew from his research in so many different areas (including biology, sociology, psychology, pharmacology, statistics,…) and made connections between those concrete facts and abstract ideas to translate them to another field: epidemiology research.

Johnson’s brain seems to operate the same way. The art of tanning leather; the propensity among certain ethnic groups to lactose intolerance; information design and mapping; nuclear weaponry; drinking brandy: what could any of these things have to do with cholera? Not much, you’d guess, if you hadn’t read the book.