At the time, it was assumed that cholera was airborne. However, Snow did not accept this 'miasma' (bad air) theory, arguing that in fact entered the body through the mouth. He published his ideas in an essay 'On the Mode of Communication of Cholera' in 1849. A few years later, Snow was able to prove his theory in dramatic circumstances. In August 1854, a cholera outbreak occurred in Soho. After careful investigation, including plotting cases of cholera on a map of the area, Snow was able to identify a water pump in Broad (now Broadwick) Street as the source of the disease. He had the handle of the pump removed, and cases of cholera immediately began to diminish. However, Snow's 'germ' theory of disease was not widely accepted until the 1860s.
This essay will focus on how the British understood and responded to the cholera epidemics that swept Britain four times from the early eighteen-thirties to the mid-eighteen-sixties, with special attention to the first epidemic and how it related to political Reform.
Snow was a sceptic of the then dominant miasma theory that stated that diseases such as cholera or the Black Death were caused by pollution or a noxious form of "bad air". The germ theory was not widely accepted by this time, so he was unaware of the mechanism by which the disease was transmitted, but evidence led him to believe that it was not due to breathing foul air. He first publicized his theory in an essay On the Mode of Communication of Cholera in 1849. In 1855 a second edition was published, with a much more elaborate investigation of the effect of the water-supply in the Soho, London epidemic of 1854.