US Rates of Travel

There are two famous graphs to show the rapid change in the rates of transportation in the US during the 1800s to 1840s. They are taken from the 1932 Atlas of the Historical Geography of the United States.

 

and were discussed in this blog post in December 2012. It would be more helpful of course to know how they constructed that information, so that similar maps could be built for Mormon missionary travel, or communication between Kirtland, OH and Far West, MS, to name but a few.