﻿230 
  

  

  Prof. 
  A. 
  S. 
  Eve 
  on 
  tlie 
  Secondary 
  y 
  Rays 
  

  

  Table 
  V. 
  (See 
  fig. 
  2.) 
  

  

  Radium 
  in 
  steel 
  2*2 
  cms. 
  thick. 
  

   Aluminium 
  screens. 
  

  

  Lhickness 
  of 
  T 
  -. 
  - 
  

  

  Lead, 
  5 
  cms. 
  

  

  screens 
  in 
  nuns. 
  ' 
  

  

  Iron, 
  5 
  cms. 
  

  

  Brick, 
  6 
  cms. 
  

  

  

  

  0-41 
  

  

  17*8 
  

  

  44 
  

  

  221 
  

  

  102 
  

  

  -.V.) 
  

  

  •56 
  

  

  10-4 
  

   470 
  

   3-56 
  

  

  3-41 
  

   3-28 
  

   304 
  

  

  8-00 
  

   4 
  09 
  

   3 
  91 
  

   3-80 
  

   335 
  

   3 
  08 
  

  

  0-82 
  

  

  1-75 
  

  

  3-40 
  

  

  7-10 
  

  

  

  

  Fi<r. 
  2. 
  

  

  to 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  16 
  

  

  

  

  

  

  

  

  

  

  14 
  

  

  12 
  

   O 
  

  

  i. 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  

  «•» 
  

  

  

  

  

  

  r?oBr 
  t 
  m 
  Steel 
  zzcm 
  

  

  

  

  

  

  

  

  Aluminium 
  Screens 
  

  

  

  

  V- 
  

  

  

  

  

  

  

  

  

  

  

  

  

  

  en 
  qh 
  

  

  

  

  

  

  

  

  

  Iron 
  

  

  

  

  

  

  

  

  

  Lead 
  

  

  

  

  

  

  

  

  

  

  

  

  