﻿780 
  Mr. 
  T. 
  J. 
  Richmond 
  on 
  the 
  Formation 
  of 
  Strict 
  

  

  not 
  appear 
  to 
  be 
  any 
  difference 
  in 
  the 
  striae-distances 
  com- 
  

   mensurate 
  with 
  the 
  difference 
  of 
  frequency. 
  

  

  Quantitative 
  Experiments. 
  

  

  The 
  previous 
  set 
  of 
  experiments 
  appear 
  to 
  show 
  very 
  little 
  

   dependence 
  of 
  strige-distance 
  on 
  electrical 
  conditions. 
  A 
  

   series 
  of 
  figures 
  was 
  now 
  obtained 
  with 
  four 
  circuits, 
  the 
  

   frequency 
  of 
  the 
  oscillations 
  produced 
  varying 
  from 
  '58 
  to 
  

   2*1 
  millions 
  per 
  second, 
  as 
  measured 
  by 
  the 
  cymometer. 
  

   These 
  frequencies 
  extended 
  over 
  the 
  whole 
  range 
  practically 
  

   of 
  the 
  cymometer, 
  so 
  it 
  was 
  not 
  possible 
  to 
  make 
  quantitative 
  

   experiments 
  with 
  circuits 
  of 
  other 
  frequencies. 
  The 
  figures, 
  

   reproductions 
  of 
  which 
  are 
  shown 
  in 
  fig. 
  lY., 
  do 
  no 
  differ 
  

   much 
  among 
  themselves 
  although 
  the 
  extreme 
  frequencies 
  

   are 
  in 
  the 
  ratio 
  of 
  4 
  : 
  1 
  nearly. 
  

  

  The 
  quantitative 
  results 
  are 
  given 
  in 
  Table 
  VI. 
  It 
  may 
  be 
  

   remarked, 
  as 
  may 
  be 
  seen 
  from 
  figs. 
  iy./& 
  h, 
  that 
  the 
  striation 
  

   did 
  not 
  usually 
  extend 
  the 
  whole 
  length 
  of 
  the 
  tubes, 
  usually 
  

   only 
  for 
  10 
  or 
  15 
  cms. 
  This 
  was 
  very 
  probably 
  due 
  to 
  the 
  

   crowding 
  up 
  of 
  the 
  lines 
  as 
  mentioned 
  above. 
  

  

  Table 
  YI. 
  

  

  Oscillation 
  Frequency. 
  

  

  Striffi-distance. 
  

  

  •58X10^ 
  per 
  sec. 
  

  

  •46 
  mm. 
  

  

  •79X10^ 
  „ 
  

  

  •38 
  „ 
  

  

  1-40 
  X10« 
  „ 
  

  

  •40 
  „ 
  

  

  2-10x106 
  „ 
  

  

  •33 
  „ 
  

  

  Discussion 
  of 
  Figures 
  (figs. 
  I.-Y.). 
  

  

  Examination 
  of 
  the 
  figures 
  shows 
  that 
  whatever 
  cause 
  or 
  

   combination 
  of 
  causes 
  governs 
  the 
  formation 
  of 
  the 
  striation 
  

   in 
  different 
  cases 
  distinctly 
  different 
  patterns 
  are 
  obtained. 
  

   These 
  differences 
  are 
  perhaps 
  more 
  strikingly 
  seen 
  in 
  the 
  

   actual 
  tubes 
  than 
  the 
  reproductions 
  given 
  in 
  figs. 
  I. 
  to 
  Y. 
  

   An 
  example 
  of 
  this 
  difference 
  is 
  afforded 
  by 
  comparison 
  of 
  

   fig. 
  III. 
  e 
  and 
  fig. 
  lY. 
  k, 
  in 
  which 
  cases 
  the 
  strise-distances 
  are 
  

   1-1 
  mm. 
  and 
  '33 
  respectively. 
  

  

  In 
  the 
  first 
  place, 
  it 
  was 
  found 
  that 
  one 
  particular 
  diameter 
  

   of 
  tube 
  gave 
  a 
  maximum 
  strise- 
  distance 
  for 
  a 
  given 
  circuit. 
  

   Again, 
  it 
  appears 
  that 
  the 
  nature 
  of 
  the 
  powder 
  has 
  an 
  

  

  