Source: Snow J. On the Mode of
Communication of Cholera, 1855.
This is Map 2 in John Snow's book. It
was used by Dr. Snow to describe the
grand experiment of 1854 comparing
cholera mortality among persons
consuming contaminated water
(Southwark and Vauxhall Company -
blue, but faded to green on the map)
versus cleaner water (Lambeth Company
- red). The overlapping area (purple but
faded to gray-red on the map) is where
John Snow analyzed the results of a
natural experiment. The 1854 map is
presented in 16 panels, sized 140-310 K.
26 Aug 2006