So what are the average sizes of these census blocks? Assuming an average is at all indicative of anything, I'd guess that it was perhaps around 1 km2 on average (going by number of census blocks). I can imagine that pieces of 1 km2 of land being totally uninhabited would be fairly easy to come across a lot of places.
Came to ask a similar question. I love me some maps and data, but the post just assumes everybody knows what a census block is. More importantly, the shape and distribution of census blocks really affect the interpretation. The uninformed reader might assume census blocks form a regular grid, but since they don't, his or her interpretations will be wrong.
And as the note about the ND-SD border mentions, there are artifacts in the map that arise from the shapes and distributions of the blocks. Whether there might be few or many other such artifacts, the cartographer gives us no information to ascertain.
