1490223

Information

• Patent Grant
• 1490223

• References
• Source

• Patent Number

  1,490,223

• Date Filed

  Not available

• Date Issued

  Tuesday, April 15, 1924
  100 years ago

• CPC

  • G01L23/06 - Indicating or recording by optical means

• US Classifications

  • 346 - Recorders
  • 073 - Measuring and testing