The underground railroad was not a real railroad to be conducted. It was an escape route for African American slaves. The main person who used this passage was Harriet Tubman, the black female Moses.
It allowed and encouraged a mass "breakout" of slaves from their owners in the 1800's. Also, was an economical downfall, but a huge civil rights movement.
James Watt discovered the steam engine. The underground railways is only an application of it. James Watt invented the engine and other people like ourselves found another use for it. Hence, there is...