﻿EFFECTS 
  OF 
  SOLAR 
  RADIATION 
  O'BRIEN 
  

  

  125 
  

  

  90 
  

  

  60- 
  

  

  W 
  

  

  60- 
  

  

  SEASONAL 
  VARIATION 
  IN 
  

   ANTIRACHITIC 
  EFFICIENCY 
  

  

  ZBram 
  OZONE 
  IN 
  ATMOSPHERE 
  

   12 
  NOON 
  

  

  Figure 
  13. 
  — 
  Seasonal 
  variation 
  in 
  solar 
  antirachitic 
  effect 
  for 
  three 
  latitudes. 
  

   (2.8 
  mm. 
  ozone 
  in 
  zenith 
  atmosphere.) 
  

  

  10 
  II 
  12 
  I 
  

  

  TIME 
  OF 
  DAY 
  

  

  Figube 
  14. 
  — 
  Hourly 
  variation 
  of 
  solar 
  antirachitic 
  effect. 
  (2.0 
  mm. 
  zenith 
  ozone, 
  

  

  33° 
  N. 
  latitude.) 
  

  

  