﻿Dielectric 
  Constant 
  of 
  Paraffins. 
  

   Table 
  VII. 
  

  

  67 
  

  

  /x 
  1 
  for 
  

   \=81'64 
  cm. 
  

  

  H 
  2 
  for 
  

   X 
  =41 
  -64 
  cm. 
  

  

  f 
  o 
  for 
  

  

  /x/for 
  

   D 
  1 
  line. 
  

  

  fi 
  2 
  ' 
  for 
  

  

  Fline. 
  

  

  ^ 
  O 
  for 
  

   \=oo 
  . 
  

  

  1-46 
  (2) 
  

  

  1-48(8) 
  

  

  1-45 
  (6) 
  

  

  1-5380 
  

  

  1-5567 
  

  

  1-498 
  

  

  1-47 
  (3) 
  

  

  1-50(4) 
  

  

  1-46(2) 
  

  

  1-5430 
  

  

  1-5589 
  

  

  1-509 
  

  

  1-48(3) 
  

  

  1-50(2) 
  

  

  1-47(7) 
  

  

  1-5505 
  

  

  1-5665 
  

  

  1-513 
  

  

  1-49(0) 
  

  

  1-51(2) 
  

  

  1-48(5) 
  

  

  1-5523 
  

  

  1-5684 
  

  

  1-519 
  

  

  Table 
  VII. 
  shows 
  the 
  results 
  obtained 
  from 
  the 
  application 
  

   of 
  this 
  formula 
  to 
  the 
  light-indices, 
  and 
  also 
  to 
  the 
  electrical 
  

   indices. 
  The 
  values 
  of 
  the 
  sixth 
  column 
  should 
  agree 
  with 
  

   those 
  of 
  the 
  third. 
  They 
  should 
  at 
  least 
  be 
  less 
  than 
  the 
  

   index 
  found 
  for 
  the 
  longest 
  wave. 
  This 
  formula 
  does 
  not 
  

   appear 
  to 
  fit 
  the 
  experimental 
  facts. 
  

  

  Conclusions. 
  

  

  1. 
  For 
  reversals 
  as 
  high 
  as 
  800,000,000 
  per 
  second 
  the 
  

   velocity 
  of 
  electrical 
  disturbances 
  along 
  magnetic 
  and 
  non- 
  

   magnetic 
  wires 
  of 
  different 
  diameters 
  is 
  the 
  same, 
  thus 
  showing 
  

   that 
  the 
  magnetic 
  properties 
  of 
  iron 
  are 
  not 
  able 
  to 
  follow 
  such 
  

   rapid 
  changes. 
  

  

  2. 
  The 
  effective 
  field 
  around 
  the 
  Lecher 
  wires, 
  as 
  far 
  as 
  it 
  

   can 
  be 
  detected 
  by 
  means 
  of 
  an 
  argon 
  tube, 
  does 
  not 
  extend 
  

   more 
  than 
  3 
  cm. 
  from 
  the 
  wires 
  ; 
  and 
  the 
  effect 
  on 
  the 
  half- 
  

   wave 
  within 
  this 
  region 
  varies 
  approximately 
  inversely 
  as 
  the 
  

   square 
  of 
  the 
  distance 
  from 
  the 
  wires. 
  

  

  3. 
  The 
  dielectric 
  constant 
  of 
  a 
  given 
  paraffin 
  increases 
  with 
  

   the 
  density 
  of 
  the 
  paraffin. 
  It 
  increases 
  rapidly 
  from 
  a 
  tem- 
  

   perature 
  20° 
  above 
  the 
  melting-point 
  to 
  a 
  temperature 
  30° 
  

   below 
  the 
  melting-point. 
  Among 
  different 
  paraffins 
  the 
  

   dielectric 
  constant 
  increases 
  as 
  the 
  melting-point 
  of 
  the 
  

   paraffin 
  increases. 
  

  

  4. 
  The 
  dielectric 
  constant 
  increases 
  as 
  the 
  wave-length 
  

   decreases. 
  It 
  is 
  greater 
  for 
  short 
  light-waves 
  than 
  it 
  is 
  for 
  

   short 
  electrical 
  waves. 
  Cauchy's 
  formula 
  as 
  a 
  means 
  of 
  

   obtaining 
  the 
  index 
  of 
  refraction 
  for 
  infinitely 
  long 
  waves 
  

   does 
  not 
  meet 
  the 
  experimental 
  facts. 
  

  

  Jefferson 
  Physical 
  Laboratory, 
  

   Harvard 
  University, 
  Cambridge, 
  U.S. 
  

  

  