﻿442 
  Mr. 
  C. 
  A. 
  Chant 
  : 
  An 
  Experimental 
  Investigation 
  

  

  the 
  same 
  diameter. 
  The 
  latter 
  were 
  made 
  by 
  covering 
  with 
  

   gold-leaf 
  accurately 
  turned 
  and 
  beautifully 
  polished 
  lignum- 
  

   vitse 
  spheres 
  of 
  the 
  required 
  sizes. 
  

  

  In 
  the 
  oscillators 
  composed 
  of 
  solid 
  spheres 
  the 
  brass 
  

   surface 
  was 
  used 
  as 
  sparking 
  faces. 
  Observation 
  showed 
  that, 
  

   in 
  air, 
  newly 
  polished 
  brass 
  is 
  at 
  least 
  equal 
  and 
  possibly 
  

   superior 
  to 
  sheet 
  platinum, 
  and 
  the 
  oil 
  dielectric 
  prevents 
  the 
  

   rapid 
  deterioration 
  of 
  the 
  surface. 
  

  

  For 
  the 
  gold-leaf 
  shells 
  platinum 
  faces 
  were 
  necessary. 
  

   Two 
  were 
  fastened 
  on 
  each 
  sphere, 
  at 
  the 
  extremities 
  of 
  a 
  

   diameter, 
  by 
  electro-deposition 
  of 
  copper. 
  

  

  The 
  results 
  obtained 
  with 
  the 
  three 
  oscillators 
  are 
  given 
  in 
  

   Tables 
  VI. 
  and 
  VII., 
  which 
  explain 
  themselves. 
  With 
  the 
  

   solid 
  spheres 
  the 
  first 
  reading 
  was 
  usually 
  the 
  highest, 
  but 
  

   with 
  the 
  shells 
  there 
  were 
  usually 
  two 
  or 
  three 
  indifferent 
  

   ones 
  to 
  start 
  with. 
  This 
  was 
  observed 
  with 
  platinum 
  faces 
  

   generally. 
  The 
  readings 
  recorded 
  are 
  : 
  for 
  the 
  solid 
  spheres, 
  

   the 
  first 
  8 
  taken; 
  for 
  the 
  4 
  cm. 
  shells, 
  the 
  first 
  8 
  ; 
  for 
  the 
  

   2'5 
  cm. 
  shells, 
  the 
  last 
  8 
  of 
  a 
  series 
  of 
  14 
  ; 
  and 
  for 
  the 
  10 
  cm. 
  

   shells, 
  all 
  the 
  satisfactory 
  readings 
  obtained. 
  

  

  Table 
  V. 
  — 
  Spheres 
  2*5 
  cms. 
  in 
  diameter. 
  

  

  Distance 
  of 
  

  

  Detector 
  position 
  ; 
  and 
  scale- 
  

  

  

  Oscillator 
  

  

  readings 
  in 
  mm. 
  

  

  

  from 
  

  

  

  

  Mean, 
  i 
  

  

  Detector 
  

   in 
  cms. 
  

  

  I. 
  11. 
  

  

  III. 
  

  

  IV. 
  

  

  1 
  

  

  

  

  

  

  

  

  

  1 
  

  

  8 
  1 
  

  

  2 
  

  

  1 
  

  

  2 
  

  

  1 
  

  

  2 
  

  

  

  

  1. 
  Solid. 
  

  

  

  30 
  

  

  40 
  

  

  44 
  

  

  41 
  

  

  40 
  

  

  46 
  

  

  39 
  

  

  46 
  

  

  35 
  

  

  41-4 
  

  

  50 
  

  

  27 
  

  

  23 
  

  

  24 
  

  

  23 
  

  

  18 
  

  

  20 
  

  

  25 
  

  

  25 
  

  

  23-1 
  1 
  

  

  100 
  

  

  15 
  

  

  13 
  

  

  12 
  

  

  8 
  

  

  11 
  

  

  10 
  

  

  12 
  

  

  13 
  

  

  11-8 
  

  

  140 
  

  

  10 
  

  

  7 
  

  

  9 
  

  

  7 
  

  

  8 
  

  

  8 
  

  

  n 
  

  

  7 
  

  

  8-4 
  • 
  

  

  200 
  

  

  7 
  

  

  7 
  

  

  7 
  

  

  4 
  

  

  7 
  

  

  4 
  

  

  10 
  

  

  5 
  

  

  6-4 
  1 
  

  

  250 
  

  

  7 
  

  

  5 
  

  

  6 
  

  

  5 
  

  

  5 
  

  

  7 
  

  

  8 
  

  

  6 
  

  

  6-1 
  i 
  

  

  300 
  

  

  7 
  

  

  6 
  

  

  5 
  

  

  4 
  

  

  4 
  

  

  5 
  

  

  4 
  

  

  5 
  

  

  5-0 
  

  

  

  2. 
  Shell. 
  

  

  

  30 
  

  

  39 
  

  

  40 
  

  

  46 
  

  

  37 
  

  

  40 
  

  

  41 
  

  

  50 
  

  

  45 
  

  

  42-3 
  

  

  50 
  

  

  18 
  

  

  22 
  

  

  20 
  

  

  16 
  

  

  22 
  

  

  24 
  

  

  27 
  

  

  28 
  

  

  22-1 
  

  

  100 
  

  

  10 
  

  

  12 
  

  

  10 
  

  

  12 
  

  

  13 
  

  

  13 
  

  

  16 
  

  

  15 
  

  

  12-6 
  

  

  140 
  

  

  8 
  

  

  7 
  

  

  8 
  

  

  7 
  

  

  8 
  

  

  7 
  

  

  12 
  

  

  12 
  

  

  8-6 
  

  

  200 
  

  

  6 
  

  

  4 
  

  

  6 
  

  

  5 
  

  

  5 
  

  

  5 
  

  

  15 
  

  

  9 
  

  

  6-9 
  

  

  250 
  

  

  6 
  

  

  6 
  

  

  6 
  

  

  4 
  

  

  7 
  

  

  5 
  

  

  10 
  

  

  11 
  

  

  6-9 
  

  

  300 
  

  

  5 
  

  

  7 
  

  

  5 
  

  

  7 
  

  

  4 
  

  

  3 
  

  

  10 
  

  

  8 
  

  

  61 
  

  

  