He drew dot, for each death caused by cholera on a street map. Then he mad an " X " for every public water pump. Then he discovered a geographical pattern of how the disease spread.
http:/en.wikipedia.org/wiki/John_Snow_(physician) I am not sure from the above article if John Snow did show that his own belief was false (that cholera was spread through the drinking water of the Broad Street pump) . He did try to demonstrate that the common belief that cholera was spread by "bad air" was false...
He didn't - that was John Snow of England. Snow didn't know EXACTLY what was in the water that caused cholera to spread, but he was able to prove, to most everyone's satisfaction, that it was contaminated water, and not foul air, that caused cholera to spread.
John Snow (15 March 1813 - 16 June 1858) was a British physician and a leader in the adoption of anaesthesia and medical hygiene. He is considered to be one of the fathers of epidemiology, because of his work in tracing the source of a cholera outbreak in Soho, England, in 1854. (from Wikipedia 2009)
john snow
In 1854 John Snow mapped the cases of cholera in Soho, London, and realised that almost all of them were likely to have taken their water from the same pump. The spread of cholera stopped when the handle of the Broad Street pump was removed.
John Snow was born on March 15, 1813.
John Snow College was created in 2001.
John Snow - cricketer - was born in 1941.
John Snow was born on March 15, 1813.
John Snow - band - was created in 2008.
Snow - John Crowley - was created in 1985.
He was just so fascinated with snow.