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Who is Walter F. White?
2m
He put his life on the line for civil rights but many don't know his name. Do you?
American Experience, TV's most-watched history series, brings to life the compelling stories from our past that inform our understanding of the world today.
Video description: As the Pennsylvania Railroad tunneled underneath the Hudson River, measurements showed that the tunnels were shifting up and down in the silty river bottom. Increasing the weight of cast iron linings did nothing to settle the tunnels, and the shifting continued. Engineers finally figured out what suddenly seemed obvious: the tunnels were moving with the tide.