John Snow

Chronicled events

1. September 8, 1854​·​A Pump at the Heart of an Outbreak
   #5773

   Cholera is caused by a poison that multiplies inside its victims, leaves them in their waste, and spreads when others swallow it, mostly in water fouled by sewage. “For the morbid matter of cholera having the property of reproducing its own kind, must necessarily have some sort of structure, most likely that of a cell.”

   #5774

   The Broad Street outbreak’s deaths cluster around one pump, and those spared drank other water: the workhouse its own well, the brewery’s men their beer. Bad air would have spared no one in the same streets.

2. 1855​·​An Experiment Nobody Planned
   #5775

   Where two water companies supply the same streets, houses drinking Thames water taken below London’s sewers lose more than eight times as many people to cholera as houses drinking water taken above them. Same streets, same air, different water.