In 185, physician John Snow set about tending to cholera victims in London. The epidemic continued to spread and spread. What could be done? Snow took the innovative approach to map the cases he found after noticing that some neighborhoods had a large amount of cases while some houses remained untouched. The infamous John Snow Map changed the future of geography, public health, and environmental design, when its findings showed that the culprit was a tainted well.

Published by C.F. Cheffins, Lith, Southhampton Buildings, London, England, 1854 in Snow, John. On the Mode of Communication of Cholera, 2nd Ed, John Churchill, New Burlington Street, London, England, 1855.