Curiosity is a powerful feeling. It is why we know the Earth is round and weighs 5 974 000 000 000 000 000 000 000 kilograms. Or why a group of wizzkids invented a Google algorithm that gave that answer in less than a second. It is also what makes ADC go around, driving students and teacher from all over Europe to embark on our Internship and Teacher Development Programmes. So let's celebrate curiosity in all its quizzical glory! Over the next few months we will introduce seven curious people who changed the world.  

Say hello to John Snow. No, not the one you think of – although he's pretty great too - but the doctor who halted an aggressive cholera outbreak in London in 1854. If you ask the science community, Snow's contributions are actually way more impressive than his fictional namesake from Game of Thrones. By discovering that cholera is caused by polluted food or water, he saved countless lives from perishing in the bacterial disease, inciting the development of water and waste systems around the world. 

Snow's stellar career began at 14 years of age as an apprentice to a surgeon in Newcastle-Upon-Tyne. Here, he encountered his first cholera outbreak and saw the devastating effect it had on the people of the town. A few years later he moved to London and became a physician. 

If you've ever set your foot in London, you're sure to have stumbled into Soho, known for its vibrant night life and avant-garde boutiques. Back in the mid 19th century, however, Soho was a filthy and overpopulated place without a proper sewer system. Waste gathered in cesspools beneath the houses and had started to overflow around this time due to an influx of people. When the London authorities decided to dump the waste in the river Thames, the water supply became contaminated. This action led to the cholera outbreak in which 616 people died and Snow would later call "the most terrible that ever occurred in this Kingdom". 

A replica of the original pump on Broadwick Street in Soho (image by  Justin Cormack )

A replica of the original pump on Broadwick Street in Soho (image by Justin Cormack)

As one of the founding members of the Epidemiological Society of London, Snow was sceptical of the widely accepted miasma theory that assumed that cholera was caused by "bad air". When cholera started spreading in London in 1854 and people panicked, many fleeing the city, Snow sought out the very epicentre of the outbreak – Soho – to look for answers. 

By talking to local residents he was able to identify the source of the outbreak as the public water pump on Broad Street (now known as Broadwick Street). He also convinced the council to remove the handle of the pump to stop people from drinking the water, polluted by runoff from a nearby cesspit - and more specifically – by a single contaminated cloth nappy. 

On proceeding to the spot, I found that nearly all the deaths had taken place within a short distance of the [Broad Street] pump. There were only ten deaths in houses situated decidedly nearer to another street-pump. In five of these cases the families of the deceased persons informed me that they always sent to the pump in Broad Street, as they preferred the water to that of the pumps which were nearer. In three other cases, the deceased were children who went to school near the pump in Broad Street
— John Snow, letter to the editor of the Medical Times and Gazette

The cholera outbreak subsided and the miasma theory was subsequently proved wrong. Snow's geographical and statistical evidence, linking the spread of cholera to polluted water, inspired great changes in water and waste systems in London and, later, in other cities around the world. According to the National Health Service, there hasn't been a cholera case originating in England or Wales for the past 100 years.  

If you find yourself wandering around Soho, you might come across the John Snow pub on a corner of Broadwick and Lexington street. A plaque on the wall commemorates the late doctors' public health legacy and a red coloured stone below marks the place where the infamous pump once stood.  

John Snow died of a stroke at 45 years of age in 1858, only four years after the outbreak. But his curiosity and compassion for people, which saved hundreds of lives and improved the lot of millions, live on. 

ADC College organises Internship and Teacher Development Programmes in London, eligible for funding from Erasmus+. Don't hesitate to contact us if you would like more information about what we do and how to get funding. Call a Country Manager today on +44 2084249424 or send a message to