﻿Smithsonian 
  Report, 
  1943. 
  —O'Brien 
  

  

  Plate 
  1 
  

  

  Using 
  only 
  ultraviolet 
  radiation 
  of 
  wave 
  length 
  33C0-3900 
  A. 
  

  

  2. 
  Using 
  only 
  infrared 
  radiation 
  of 
  wave 
  length 
  7600-8000 
  A. 
  

  

  PHOTOGRAPHS 
  ON 
  PANCHROMATIC 
  FILM 
  OF 
  UNPIGMENTED 
  SKIN 
  

   AND 
  MAGNESIUM 
  CARBONATE 
  COMPARISON 
  BLOCK. 
  

  

  