Cholera Epidemic of 1855-1856 Mapped Using Google Earth

This will need a few minutes to load, but once ready, this video animates the spread of cholera during the great epidemic of 1855-1856.  It focuses on the western seaboard, and shows how it struck the ports of Bahia (July, 1855) and Rio de Janeiro (Sept, 1855) moving into the interior, almost always along waterways.  I have animated these maps before, but this is the first time using Google Earth.  More information on the spatial movement of this epidemic can be found here.