Dr John Snow, a physician and specialist in medical ... Snow set out to prove his theory that unclean water caused the spread of cholera. He used a map to plot where cholera deaths had taken ...

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 ...

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 ... the cases on a map.