Geiger Counter Detector of Radioactive Ink

Abstract

In reference (a) the Office of Censorship requested this Laboratory to develop a rapid means of inspecting mail for radioactive ink messages. It was suspected that the radioactive ink employed by enemy agents would be prepared from radium-sodium. By proper treatment, this ink could be rendered safe from detection by the usual chemical tests. The message could be revealed by placing the letter sheet in contact with photographic film and exposing for a few hours, which was too - lengthy a time for Censorship inspection. In the following paragraphs is described a Geiger counter device which appeared to be sufficiently sensitive and rapid for the purpose.

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Document Details

Document Type
Technical Report
Publication Date
May 20, 1943
Accession Number
AD1175583

Entities

People

  • E. O. Hulbert
  • Herbert Freidman

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Absorption
  • Aluminum
  • Barometric Pressure
  • Censorship
  • Charged Particles
  • Construction
  • Counters
  • Detection
  • Detectors
  • Deuterons
  • Efficiency
  • Electrons
  • Geiger Counters
  • Inspection
  • Photographic Film
  • Positron Emissions
  • Positrons

Readers

  • Military History of the United States in the 20th Century.
  • Solar Physics
  • Vision Science/Vision Psychology/Cognitive Neuroscience.