There is yet one additional way that the Mississippi River divides America. It is by population. Now, I have studied this extensively, and in fact I researched these locations on site in June, 2009. It turns out that the midpoint of the Mississippi River and the population centroid of the United States essentially overlap in Eastern Missouri!
Therefore, we can say that America is divided, along the Mississippi River, not only geographically and geologically, but demographically, by population center as well. The following references all discuss the population center as derived post-2000 Census-
I will be referring to the work of Aboufadel & Austin (2006), as well as to Richeson (2004), but the U.S. Census raw data can be accessed here-
[link to www.nationalatlas.gov
The two non-government sources, using the U.S. Government’s own data, convincingly reveal that the Government method is significantly flawed, which should surprise no-one. So, let’s look at these two independent sources and “discard” the Government midpoint of Edgar Springs, Missouri, which is significantly south of the locations obtained by the independent researchers with their superior methods. A review of the results of Aboufadel and Austin (2006) suggests the population midpoint of America to be approximately one (1) mile north of Americus, Missouri in southern Montgomery County, whereby Richeson (2004) shows this midpoint to be approximately at Montgomery City, Missouri, in north central Montgomery County. The centroid of these two midpoints is shown in the image below-
The Center of the Father of Waters:
What, then, about the center of the Mississippi River- is it related to the population center? Indeed it is, remarkably. There are two legitimate means with which to calculate this river midpoint. First, we can draw a line, on a large wall map or Google Earth, between the start of the Mississippi River in northern Minnesota and the end of the river in the delta of Louisiana. We next measure that line, and then derive the halfway point by length in miles. I have determined this point to be between the towns of Vienna and Belle, in Maries County, Missouri. This location is, not surprisingly, on land.
The other, more difficult, method is to use the navigable midpoint; in other words, to determine the middle of the river in today’s river miles but based on the morphology of the river circa 1776. I was able to achieve this by counting river miles downstream from the start of the river, as well as upstream from its mouth. Using historic information from Elliott (1932) as well as official U.S. Government maps “Mississippi River Navigation Charts”, US Army Corps of Engineers (2001), I was able to determine this to be 14 miles southeast of Hannibal, Missouri, in Pike County. This is amazing considering the connection of the man most associated with the Mississippi River, beloved American author Mark Twain and the town of Hannibal which features in several of his classic works!
To obtain the centroid, then, we take the point half way between these two measurements. The combined Mississippi River centroid is thereby determined to be in east central Montgomery County, Missouri, near I-70.
The Divisible Center of America:
So, precisely what can we say about the relationship of the Mississippi River and population centroids of the United States of America as determined by the above methods? They are only 2.5 miles apart, with the population center south southeast of the Mississippi River centroid!
Amazing for a country of this size, which encompasses over 3.7 million square miles, and these points can therefore be considered statistically “spot-on”-