How to Translate Local Descriptions of Geography Into Coordinates

When i started dealing with cholera patients, the idea somebody walks into your cholera centr or later ebola centre, and they're desperately ill, their first question is where did you just come from? So to make this concrete, i'd like an ambulance. Well, where are you? Well, there's a mango tree over on te left, and then there's a building with a red roof. And we're somewhere in the commune of macareco. We'll see you when we get there. The ability to translate local descriptions of geography into coordinates is a huge gap. I mean, john snow, the good candidate for greatest doctor in history, his claim to