Unclassed Choropleth

Source -
http://www.math.yorku.ca/SCS/Gallery/milestone/thumb5/popup/bssn1_popup1-19.htm

A unclassed choropleth map has the use of shading of places. This map is of 1826 France and it depicts the literacy rates, the darker the section of the country has the most literacy rates and places with lighter shades or no shades at all have the least literacy people living in it. This map doesn't use a key to represent anything. As seen in this map most people in 1826 were not able to read or write which makes a lot of sense because it not many people back then took the time to learn it. Also the area that has the darkest spot is Paris where most of the higher class lived at that time.