Very interesting. But the focus on New York probably skews the analysis a lot, particularly in early years when rivers and canals would have been important routes. Notice the bend of the 1800 curves up the eastern NY border, and into southeastern Pennsylvania? I bet those reflect the use of the Hudson and Delaware rivers for travel, and possibly linkage to other rivers like the Ohio, Susquehanna and Potomac. Likewise I suspect that in 1830 Chicago was probably closer to New Orleans, on the Mississippi, than it was to New York.
Likewise the transport of goods, rather than passengers, was probably more important in forming perceptions of distance, as that's what would drive commerce and thus ongoing relationships.
Attention to goods and other point pairings probably matter a lot when you get to 1857. I expect internal communications, of goods, in the South reflected high proximity to the nearest port, and that NY was essentially on the other side of the moon. Whereas the North was probably much more homogenous in its travel times (proportionately more railroad, less river) -- but largely isolated from the South. Which would have done a lot to foster disunion among the two geographies.
That view would probably also say a lot about the border states, I bet that would show these were essentially islands unto themselves.
That's not really a skew so much as a reflection of the realities of the time, though. If you were lucky enough to want to go somewhere along a canal route, you traveled fast; otherwise you traveled slow. (Which meant most trips were slow.)
Attention to goods and other point pairings probably matter a lot when you get to 1857. I expect internal communications, of goods, in the South reflected high proximity to the nearest port, and that NY was essentially on the other side of the moon. Whereas the North was probably much more homogenous in its travel times (proportionately more railroad, less river) -- but largely isolated from the South.
You might be surprised. Antebellum New York actually had strong commercial ties to the South, primarily from acting as a distribution center for Southern cotton to the rest of the North. These ties were so strong that Fernando Wood, the mayor of New York City during the secession crisis, actually led a short-lived movement to take New York out of the Union and establish it as a neutral "free city" so that it could continue in the cotton trade. (See http://opinionator.blogs.nytimes.com/2011/01/06/first-south-... for a good account of this period.) There was actually a fair bit of support in the city for Wood's plan until the Confederates fired on Fort Sumter, setting off a wave of pro-Union support in the North that swamped it.
New York was the commercial and population center of the 13 Colonies and early US, a position it never really ceded, though New York State was surpassed in population by California and then Texas in the 1960s and 1980s. Point-to-point travel from other locations would have been largely similar to
Water travel was the first "highway" system in the US, first along the seacoast, then along rivers, then along canals (notably the Erie Canal, opened in 1825). The Saint Lawrence Seaway, offering deepwater access to Chicago and northern Minnesota, and the Mississippi-Missouri-Ohio river systems, offering access to roughly 1/3 of the present conterminious United States, was (and is) hugely important to commerce. http://en.wikipedia.org/wiki/File:Mississippi_watershed_map_...
Rail, then highway, then air travel are faster than ships and barges, but if you want to maximize ton-miles per hour, you bulk-load or container-load a ship or barge. Coal, grain, and other bulk goods simply cannot be moved economically by other means, and issues such as the lack of water flow on the Mississippi River will have huge knock-on effects on commerce.
During the Civil War, the Union focused a great deal of effort on blockading and controlling southern ports, particularly Savannah and New Orleans, through which the bulk of Confederate exports (and revenues) flowed. Chocking off the South's access to finance had a great deal to do with eventual Union victory.
Likewise the transport of goods, rather than passengers, was probably more important in forming perceptions of distance, as that's what would drive commerce and thus ongoing relationships.
Attention to goods and other point pairings probably matter a lot when you get to 1857. I expect internal communications, of goods, in the South reflected high proximity to the nearest port, and that NY was essentially on the other side of the moon. Whereas the North was probably much more homogenous in its travel times (proportionately more railroad, less river) -- but largely isolated from the South. Which would have done a lot to foster disunion among the two geographies.
That view would probably also say a lot about the border states, I bet that would show these were essentially islands unto themselves.