﻿778 
  Mr. 
  T. 
  J. 
  Richmond 
  on 
  the 
  Formation 
  of 
  Strice 
  

  

  parallel 
  with 
  its 
  jars. 
  These 
  figures 
  are 
  reproduced 
  in 
  fig. 
  III. 
  

   (PI. 
  XXy.), 
  in 
  which 
  a, 
  h, 
  c, 
  d, 
  &c. 
  are 
  in 
  descending 
  order 
  

   of 
  frequency. 
  The 
  quantitative 
  results 
  of 
  this 
  set 
  of 
  obser- 
  

   vations 
  are 
  shown 
  in 
  Table 
  V. 
  

  

  Table 
  V. 
  

  

  -Variation 
  of 
  striae-distance 
  and 
  electrical 
  

   conditions. 
  

  

  Description 
  of 
  Sparking 
  Circuit. 
  

  

  Striae-distances. 
  

  

  a. 
  Machine 
  ; 
  and 
  rectangular 
  circiiit 
  200x30 
  cms. 
  . 
  

  

  •68 
  mm. 
  

  

  b. 
  Machine 
  ; 
  rectangular 
  circuit 
  ; 
  and 
  one 
  large 
  

   leyden-jar 
  in 
  parallel 
  with 
  the 
  jars 
  of 
  

   the 
  machine 
  

  

  •61 
  „ 
  

  

  •84 
  „ 
  

   •80 
  „ 
  

  

  c. 
  Machine 
  ; 
  rectangular 
  circuit 
  ; 
  and 
  six 
  jars 
  of 
  

   various 
  capacities 
  in 
  parallel 
  with 
  the 
  

   jars 
  of 
  the 
  machine 
  

  

  d. 
  Machine; 
  rectangular 
  circuit; 
  and 
  twelve 
  jars 
  

   in 
  parallel 
  with 
  jars 
  of 
  the 
  machine 
  ... 
  

  

  e. 
  Machine; 
  rectangular 
  circuit; 
  and 
  a 
  battery 
  of 
  

   6 
  large 
  jars 
  together 
  with 
  7 
  other 
  jars 
  

   in 
  parallel 
  with 
  jars 
  of 
  the 
  machine 
  ... 
  

  

  1-1 
  „ 
  

  

  Spark 
  2 
  cms. 
  long 
  in 
  all 
  cases. 
  

  

  

  Variation 
  of 
  stricE-di 
  stance 
  along 
  the 
  same 
  tube. 
  

  

  In 
  the 
  earlier 
  experiments 
  it 
  was 
  thought 
  that 
  a 
  variation 
  

   in 
  the 
  distribution 
  of 
  the 
  lines 
  forming 
  the 
  pattern 
  for 
  a 
  

   given 
  spark 
  was 
  observed 
  along 
  the 
  length 
  of 
  the 
  same 
  tube. 
  

   To 
  investigate 
  this 
  question 
  tubes 
  120 
  cms. 
  long 
  and 
  1 
  cm. 
  

   in 
  diameter 
  were 
  taken, 
  and 
  the 
  figure 
  for 
  various 
  sparks 
  

   was 
  obtained. 
  

  

  The 
  figures 
  in 
  these 
  cases 
  (see 
  fig. 
  V., 
  PL 
  XXVI.) 
  were 
  

   remarkably 
  well-defined. 
  In 
  addition 
  to 
  this, 
  there 
  were 
  in 
  

   the 
  various 
  tubes, 
  four 
  of 
  which 
  were 
  used 
  for 
  different 
  sparks, 
  

   distinct 
  periodic 
  variations 
  along 
  the 
  lengths 
  of 
  the 
  tubes 
  in 
  

   the 
  strise-distance. 
  In 
  these 
  cases 
  the 
  tubes 
  were 
  supported 
  by 
  

   a 
  clamp 
  near 
  one 
  end. 
  The 
  periodic 
  variations 
  just 
  mentioned 
  

   were 
  visible 
  from 
  the 
  beginning, 
  but 
  became 
  more 
  in 
  evidence 
  

   by 
  long 
  continued 
  sparking. 
  The 
  distance 
  between 
  two 
  suc- 
  

   cessive 
  places 
  of 
  rarefaction 
  or 
  compression 
  of 
  the 
  lines 
  is 
  

   seen 
  from 
  figs. 
  V. 
  a 
  & 
  6 
  to 
  be 
  approximately 
  constant 
  and 
  

   somewhat 
  different 
  for 
  the 
  various 
  tubes, 
  being 
  between 
  

   3 
  and 
  4 
  centimetres 
  in 
  Va... 
  

  

  The 
  figures 
  obtained 
  in 
  these 
  tubes 
  are 
  shown 
  graphically 
  

   in 
  fig. 
  4 
  (p. 
  781). 
  

  

  