﻿234 
  Prof. 
  E. 
  H. 
  Bear 
  ton 
  and 
  Mr. 
  T. 
  J. 
  Richmond 
  on 
  

  

  the 
  quality 
  of 
  tones 
  emitted 
  by 
  vibrating 
  strings^ 
  we 
  have 
  

   not 
  the 
  like 
  knowledge 
  of 
  the 
  quality 
  emitted 
  by 
  stringed 
  

   instrume7its. 
  

  

  The 
  preliminary 
  work 
  was 
  done 
  with 
  the 
  monochord 
  and 
  

   dealt 
  with 
  the 
  belly 
  *, 
  the 
  air 
  f 
  in 
  the 
  sound-box, 
  and 
  the 
  

   bridge 
  % 
  respectively. 
  

  

  The 
  present 
  paper 
  is 
  the 
  first 
  instalment 
  of 
  work 
  on 
  the 
  

   violin 
  and 
  is 
  in 
  the 
  main 
  confined 
  to 
  the 
  g 
  string. 
  

  

  Speaking 
  generally, 
  perhaps 
  the 
  chief 
  distinction 
  between 
  

   the 
  curves 
  here 
  obtained 
  for 
  the 
  violin 
  belly 
  and 
  those 
  for 
  

   the 
  monochord 
  lies 
  in 
  the 
  fact 
  that 
  to 
  the 
  eye 
  the 
  violin- 
  curves 
  

   appear 
  simpler 
  and 
  smoother. 
  Often 
  that 
  means, 
  however, 
  

   that 
  they 
  have 
  a 
  fuller 
  retinue 
  of 
  upper 
  partials, 
  but 
  without 
  

   undue 
  prominence 
  of 
  any 
  one 
  of 
  them, 
  as 
  was 
  sometimes 
  

   noticeable 
  with 
  the 
  monochord. 
  But 
  perhaps 
  it 
  is 
  still 
  too 
  

   soon 
  to 
  draw 
  such 
  conclusions 
  safely. 
  Incidentally 
  the 
  pitch 
  

   of 
  best 
  resonance 
  was 
  found 
  by 
  use 
  of 
  the 
  French-horn, 
  and 
  

   a 
  wandering 
  of 
  the 
  vibrations 
  of 
  the 
  belly 
  over 
  its 
  surface 
  

   was 
  detected. 
  

  

  Optical 
  Ar7'angements, 
  — 
  The 
  general 
  arrangement 
  of 
  the 
  

   apparatus 
  for 
  the 
  experiments 
  may 
  be 
  understood 
  from 
  fig. 
  1 
  

   (PL 
  IV.). 
  In 
  this 
  Tj'and 
  T2 
  indicate 
  the 
  two 
  tables, 
  the 
  first 
  

   carrying 
  the 
  lantern 
  L 
  and 
  the 
  lenses, 
  the 
  second 
  holding 
  

   the 
  violin 
  Y. 
  These 
  tables 
  were 
  each 
  mounted 
  on 
  pieces 
  of 
  

   rubber 
  and 
  lead 
  to 
  cut 
  off 
  the 
  vibrations 
  of 
  the 
  one 
  from 
  

   communication 
  via 
  the 
  floor 
  to 
  the 
  other. 
  

  

  Since 
  together 
  with 
  the 
  vibrations 
  of 
  the 
  belly, 
  those 
  of 
  

   the 
  string 
  were 
  to 
  be 
  recorded 
  also, 
  the 
  light 
  coming 
  from 
  

   the 
  electric 
  arc-lantern 
  needed 
  dividing 
  into 
  two 
  parts. 
  One 
  

   part 
  passed 
  through 
  the 
  vertical 
  slit 
  S, 
  then 
  through 
  a 
  lens 
  Li 
  

   (with 
  diaphragm), 
  which 
  focussed 
  a 
  real 
  image 
  of 
  the 
  slit 
  

   on 
  the 
  string. 
  The 
  light 
  then 
  passed 
  to 
  the 
  plane 
  mirror 
  M, 
  

   held 
  just 
  behind 
  the 
  string. 
  This 
  reflected 
  a 
  diverging 
  beam 
  

   of 
  light 
  to 
  the 
  lens 
  1^2, 
  which 
  was 
  thus 
  focussed 
  upon 
  the 
  

   photographic 
  plate 
  P, 
  the 
  light 
  passing 
  through 
  the 
  opening 
  

   of 
  the 
  door 
  D 
  to 
  the 
  dark 
  room. 
  

  

  Since 
  the 
  first 
  real 
  image 
  of 
  the 
  slit 
  was 
  focussed 
  upon 
  

   the 
  string 
  the 
  second 
  image 
  on 
  the 
  plate 
  was 
  crossed 
  by 
  the 
  

   shadow 
  of 
  the 
  string. 
  Thus, 
  as 
  the 
  string 
  rises 
  and 
  falls 
  in 
  

   its 
  vibration, 
  the 
  shadow 
  of 
  it 
  falls 
  and 
  rises 
  on 
  the 
  plate. 
  

   This 
  of 
  course 
  would 
  only 
  produce 
  a 
  blur 
  if 
  the 
  plate 
  were 
  

   at 
  rest. 
  But 
  the 
  plate 
  is 
  shot 
  in 
  horizontal 
  rails 
  by 
  a 
  

   catapult 
  of 
  indiarubber 
  cords, 
  so 
  arranged 
  that 
  the 
  velocity 
  

  

  * 
  Barton 
  & 
  Garrett, 
  Phil. 
  Mag. 
  July 
  1905, 
  pp. 
  149-157. 
  

   t 
  Barton 
  & 
  Penzer, 
  Phil. 
  Mag. 
  Dec. 
  190G, 
  pp. 
  576-578. 
  

   \ 
  Barton 
  & 
  Penzer, 
  Phil. 
  Mag. 
  April 
  1907, 
  pp. 
  446-452. 
  

  

  