Railroad workers have an antiseptic -- but descriptive -- word for what happened next: Telescoping.

CNN: Welcome to obscure Washington, D.C.

Quiet-car "vigilantes, " as some railroad workers call the self-styled enforcers, step in.

WSJ: Shhh! 'Quiet Cars' Turn Commuters Into Librarians

Carharrt, the workwear apparel brand, was founded in Detroit, Michigan in the late nineteenth century and originally made rugged clothing for railroad workers.

FORBES: Carharrt x Chrysler: Imported From Detroit

Only when the World Trade Center staff member has radioed back can the railroad and its workers be sure that each train has cleared the tunnel, and that there is no risk of a collision.

WSJ: PATH's Road Back Is Rocky

During that period, the railroad actually managed to employ fewer workers, on average, than a year earlier.

FORBES: Connect

As the waters recede, the task facing rescue workers is to bring the animals safely back across a highway and railroad, into the park.

BBC: News | South Asia | Flood aid for tigers at risk