Determining longitude required an absolute measurement of time.
A character in George R. R. Martin's Game of Thrones?
He was an English physician who had a big problem in 1854.
The miasma theory of disease was popular.
Louis Pasteur would not do his germ theory studies until 1860.
On August 31, 1854, after outbreaks in other parts of London, a major outbreak of cholera reached Soho. Over the next three days, 127 people on Broad Street had died. By the end of the outbreak 616 would die.
OpenStreetMap is a community driven mapping project based on local knowledge. It is like the Wikipedia of maps in that it accepts data from many contributors, and users are free to use the data in various ways like designing apparel that uses maps.
You can help whereever there is a humanitarian crisis.
CartoDB is a map visualization engine that can turn tables of data into beautiful maps.