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Compressed Air in the Tunnels

  • Aired: 02/18/2014
  • 02:42
  • Rating: NR
Work never stopped on the Pennsylvania Railroad’s tunneling projects; there were three 8-hour shifts a day, 7 days a week. As the workers dug under the river bed, compressed air was pumped in to keep the water out of the tunnels. To bore under the river, the engineers used a Greathead shield, a steel cylinder with a diameter of 23 feet that weighed nearly 200 tons.
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Compressed Air in the Tunnels
Compressed Air in the Tunnels
Compressed air was used to keep the water out of the Pennsylvania RR's Manhattan tunnels.
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