Railroads in 1870

Mostly the North East.  What else?  A mesh of telegraph lines all over the rail line.  The USA had about 35 million people about 20 million in the North East.  That is  lot of rail road on the map, and they require big yards inside the major cities, the passenger stations occupying the city center often.

That is the railroad economy, big, loud, and plenty of heavy iron.   What were the Morse code geeks doing? Disrupting the flow, using telegraphed information to mix and match cargo at the sources, use the rail off hours.   They made the loot by managing inventory at a distance, they reduce the need to move big iron.  Everywhere, always, telegraph, radio, web; its always the geeks.