John Snow’s data journalism: the cholera map that changed the world | News | guardian.co.uk
▻http://www.guardian.co.uk/news/datablog/2013/mar/15/john-snow-cholera-map
How often does a map change the world? In 1854, one produced by Doctor John Snow, altered it forever.
In the world of the 1850s, #cholera was believed to be spread by miasma in the air, germs were not yet understood and the sudden and serious outbreak of cholera in London’s Soho was a mystery.
So Snow did something data journalists often do now: he mapped the cases. The map essentially represented each death as a bar, and you can see them in the smaller image above.
It became apparent that the cases were clustered around the pump in Broad (now Broadwick) street.
