494765

Information

• Patent Grant
• 494765

• References
• Source

• Patent Number

  494,765

• Date Filed

  Not available

• Date Issued

  Tuesday, April 4, 1893
  131 years ago

• CPC

  • G01J1/54 - by observing photo-reactions between gases

• US Classifications

  • 200 - Electricity: circuit makers and breakers
  • 250 - Radiant energy
  • 337 - Electricity: electrothermally or thermally actuated switches