 Guerry's first work on what would come to be called "moral statistics" was a large, one page sheet containing three shaded maps of France, prepared together with the Venetian geographer, Adriano Balbi in 1829.These showed the departments of France, shaded according to crimes against persons, crimes against
property, and school instruction.Such statistical maps, now called choropleth maps had just been invented in 1826 by Baron Charles Dupin.