Summary

Snow determined that deaths on Broad Street occurred in most every house near the pump. The deaths in the nearby areas were more sporadically located. But this would not be enough evidence to convince the miasmatists – they’d believe a pocket of bad air over the street was responsible. He needed some aberrations, some exceptions to the rule. He needed to find healthy residents who were not expected to die but succumbed to cholera. When Snow arrived at the tailor’s apartment, it was too late – the whole family had died.

Snow had imagined drawing maps of the Golden Square to create a visual representation of the patterns of disease and death. There would be a boundary around the Broad Street pump at the center of the map where he would expect to see the most cases. Those residences outside...