One of the most important maps in human history was not created by a professional cartographer or navigator. It was made in 1854 by a London physician named John Snow. He suspected that the cholera ...

Dr John Snow, a physician and specialist ... Dr Snow's map showing the cases of cholera in Broad Street, London, 1854. The map helped to identify the source of the outbreak - a polluted water ...

For 14 weeks in the late summer of 1853, London suffered one of its worst cholera outbreaks. The leading voices in medicine believed the disease emanated from the foul gasses of London’s polluted ...

John Snow is often called the founder of epidemiology, the study of health in populations. He is best known for his work on tracking the spread of cholera during an epidemic in London in 1854.