﻿Aepinus 
  Atomized. 
  273 
  

  

  F, 
  the 
  intensity 
  of 
  the 
  electric 
  field, 
  as 
  it 
  was 
  rigorously 
  for 
  

   n 
  single 
  atom 
  through 
  the 
  whole 
  range 
  up 
  to 
  the 
  disruptional 
  

   value 
  of 
  F; 
  but 
  will 
  tend 
  to 
  increase 
  more 
  than 
  in 
  simple 
  

   proportion 
  to 
  the 
  value 
  of 
  F; 
  though 
  for 
  small 
  practical 
  

   values 
  of 
  F 
  the 
  law 
  of 
  simple 
  proportion 
  is 
  still 
  very 
  nearly 
  

   fulfilled. 
  

  

  § 
  29. 
  Raise 
  the 
  temperature 
  now 
  to 
  anything 
  under 
  that 
  

   at 
  which 
  the 
  solid 
  would 
  melt. 
  This 
  sets 
  the 
  electrions 
  to 
  

   performing 
  wildly 
  irregular 
  vibrations 
  and 
  rotations, 
  so 
  that 
  

   some 
  of 
  them 
  will 
  occasionally 
  be 
  shot 
  out 
  of 
  their 
  atoms. 
  

   Each 
  electrion 
  thus 
  shot 
  out 
  will 
  quickly 
  either 
  fall 
  back 
  into 
  

   the 
  atom 
  from 
  which 
  it 
  has 
  been 
  ejected, 
  or 
  will 
  find 
  its 
  way 
  

   into 
  another 
  atom. 
  If 
  the 
  body 
  be 
  in 
  an 
  electric 
  field 
  F, 
  a 
  

   considerable 
  proportion 
  of 
  the 
  electrions 
  which 
  are 
  shot 
  out 
  

   will 
  find 
  their 
  way 
  into 
  other 
  atoms 
  in 
  the 
  direction 
  in 
  which 
  

   they 
  are 
  pulled 
  by 
  F 
  ; 
  that 
  is 
  to 
  say, 
  the 
  body 
  which 
  was 
  an 
  

   infinitely 
  perfect 
  insulator 
  at 
  zero 
  absolute 
  temperature 
  has 
  

   now 
  some 
  degree 
  of 
  electric 
  conductivity, 
  which 
  is 
  greater 
  

   the 
  higher 
  the 
  temperature. 
  There 
  can 
  be 
  no 
  doubt 
  that 
  

   this 
  is 
  a 
  matter-of-fact 
  explanation 
  of 
  the 
  electric 
  conductivity, 
  

   which 
  so 
  nearly 
  perfect 
  an 
  insulator 
  as 
  the 
  flint 
  glass 
  of 
  my 
  

   quadrant 
  electrometer 
  at 
  atmospheric 
  temperature 
  shows, 
  

   when 
  heated 
  to 
  far 
  below 
  its 
  melting-point, 
  (according 
  to 
  

   Prof. 
  T.Gray 
  * 
  -98.10" 
  24 
  at 
  60° 
  cent.; 
  4-9.10- 
  24 
  at 
  100°; 
  

   8300. 
  10~ 
  24 
  at 
  200° 
  cent.) 
  ; 
  and 
  of 
  the 
  enormous 
  increase 
  of 
  

   electric 
  conductivity 
  of 
  rare 
  earths 
  at 
  rising 
  temperatures 
  

   above 
  800° 
  C, 
  so 
  admirably 
  taken 
  advantage 
  of 
  by 
  Professor 
  

   Nernst 
  in 
  his 
  now 
  celebrated 
  electric 
  lamp. 
  

  

  § 
  30. 
  If 
  the 
  hypotheses 
  suggested 
  in 
  the 
  present 
  com- 
  

   munication 
  are 
  true, 
  the 
  electric 
  conductivity 
  of 
  metals 
  must 
  

   be 
  explained 
  in 
  the 
  same 
  way 
  as 
  that 
  of 
  glass, 
  guttapercha, 
  

   vulcanite, 
  Nernst 
  filament, 
  &c, 
  with 
  only 
  this 
  difference, 
  

   fhat 
  the 
  metallic 
  atom 
  must 
  be 
  so 
  crowded 
  with 
  electrions 
  

   that 
  some 
  of 
  them 
  are 
  always 
  being 
  spilt 
  out 
  of 
  each 
  atom 
  

   by 
  the 
  intermolecular 
  and 
  electrionic 
  thermal 
  motions, 
  not 
  

   only 
  at 
  ordinary 
  atmospheric 
  temperatures, 
  and 
  higher, 
  but 
  

   even 
  at 
  temperatures 
  of 
  less 
  than 
  16° 
  centigrade 
  above 
  the 
  

   absolute 
  zero 
  of 
  temperature. 
  I 
  say 
  16° 
  because 
  in 
  Dewar's 
  

   Bakerian 
  Lecture 
  to 
  the 
  Royal 
  Society 
  of 
  London, 
  June 
  13, 
  

   1901, 
  " 
  The 
  Nadir 
  of 
  Temperature/' 
  we 
  find 
  that 
  platinum, 
  

   gold, 
  silver, 
  copper, 
  and 
  iron 
  have 
  exceedingly 
  high 
  electric 
  

   conductivity 
  at 
  the 
  temperature 
  of 
  liquid 
  hydrogen 
  boiling 
  

   under 
  30 
  mms. 
  of 
  mercury, 
  which 
  must 
  be 
  something 
  between 
  

   20°*5, 
  the 
  boiling-point 
  of 
  hydrogen 
  at 
  760 
  mms. 
  pressure, 
  

  

  * 
  Proc. 
  Roy. 
  Soc. 
  Jan. 
  12, 
  1882. 
  

   Phil. 
  Mag. 
  S. 
  6. 
  Vol. 
  3. 
  No. 
  15. 
  March 
  1902. 
  T 
  

  

  