1173158

Information

• Patent Grant
• 1173158

• References
• Source

• Patent Number

  1,173,158

• Date Filed

  Not available

• Date Issued

  Tuesday, February 29, 1916
  108 years ago

• CPC

  • E21D9/0621 - Shield advancing devices

• US Classifications

  • 405 - Hydraulic and earth engineering
  • 175 - Boring or penetrating the earth
  • 299 - Mining or in situ disintegration of hard material