Earlier this year , I interviewed a retired steelworker named Tom Wells, who had taken hundreds of color photographs of Chicago’s freight train tunnels in the late ’80s and early ’90s. At their peak, the tunnels encompassed sixty miles of track, forty feet below the sidewalk, extending from Superior Street south to 16th. Inside, small train cars—built and controlled by the Chicago Tunnel Company—carried coal, ash, mail, home goods, and newsprint from warehouses to ferry terminals along the river, making stops at buildings connected to the underground tracks by elevator shafts. The tunnels closed in 1954, by that time more of a curiosity than a financially viable operation.…