﻿272 
  Lord 
  Kelvin 
  : 
  

  

  inertia 
  of 
  an 
  electrion) 
  seem 
  to 
  show 
  that 
  the 
  intermolecular 
  

   •electric 
  forces 
  are 
  more 
  than 
  amply 
  great 
  enough 
  to 
  account 
  

   for 
  heat 
  of 
  chemical 
  combination, 
  and 
  every 
  mechanical 
  

   action 
  manifested 
  in 
  chemical 
  interactions 
  of 
  all 
  kinds. 
  We 
  

   might 
  be 
  tempted 
  to 
  assume 
  that 
  all 
  chemical 
  action 
  is 
  electric, 
  

   .•and 
  that 
  all 
  varieties 
  of 
  chemical 
  substance 
  are 
  to 
  be 
  explained 
  

   by 
  the 
  numbers 
  of 
  the 
  electrions 
  required 
  to 
  neutralize 
  an 
  

   atom 
  or 
  a 
  set 
  of 
  atoms 
  (§ 
  6 
  above); 
  but 
  we 
  can 
  feel 
  no 
  

   ■satisfaction 
  in 
  this 
  idea 
  when 
  we 
  consider 
  the 
  great 
  and 
  

   wild 
  variety 
  of 
  quality 
  and 
  affinities 
  manifested 
  by 
  the 
  

   different 
  substances 
  or 
  the 
  different 
  u 
  chemical 
  elements"; 
  

   and 
  as 
  we 
  are 
  assuming 
  the 
  electrions 
  to 
  be 
  all 
  alike, 
  we 
  

   must 
  fall 
  back 
  on 
  Father 
  Boscovich, 
  and 
  require 
  him 
  to 
  

   explain 
  the 
  difference 
  of 
  quality 
  of 
  different 
  chemical 
  sub- 
  

   stances 
  by 
  different 
  laws 
  of 
  force 
  between 
  the 
  different 
  atoms. 
  

  

  § 
  27. 
  Consider 
  lastly 
  a 
  solid; 
  that 
  is 
  to 
  say, 
  an 
  assemblage 
  

   in 
  which 
  the 
  atoms 
  have 
  no 
  relative 
  motions, 
  except 
  through 
  

   ranges 
  small 
  in 
  comparison 
  with 
  the 
  shortest 
  distances 
  be- 
  

   tween 
  their 
  centres 
  *, 
  The 
  first 
  thing 
  that 
  we 
  remark 
  is 
  that 
  

   every 
  solid 
  would, 
  at 
  zero 
  of 
  absolute 
  temperature 
  (that 
  is 
  to 
  

   say 
  all 
  its 
  atoms 
  and 
  electrions 
  at 
  rest), 
  be 
  a 
  perfect 
  insulator 
  

   of 
  electricity 
  under 
  the 
  influence 
  of 
  electric 
  forces, 
  moderate 
  

   -enough 
  not 
  to 
  pluck 
  electrions 
  out 
  of 
  the 
  atoms 
  in 
  which 
  they 
  

   rest 
  stably 
  when 
  there 
  is 
  no 
  disturbing 
  force. 
  The 
  limiting- 
  

   value 
  of 
  F 
  here 
  indicated 
  for 
  perfect 
  insulation, 
  I 
  shall 
  for 
  

   'brevity 
  call 
  the 
  disruptional 
  force 
  or 
  disruptional 
  intensity. 
  

   It 
  is 
  clear 
  that 
  this 
  disruptional 
  force 
  is 
  smaller 
  the 
  greater 
  

   the 
  number 
  of 
  electrions 
  within 
  an 
  atom. 
  

  

  § 
  28. 
  The 
  electro-inductive 
  permeability 
  of 
  a 
  solid 
  at 
  zero 
  

   temperature 
  is 
  calculable 
  by 
  the 
  static 
  dynamics 
  of 
  § 
  24, 
  

   modified 
  by 
  taking 
  into 
  account 
  forces 
  on 
  the 
  electrions 
  of 
  

   one 
  atom 
  due 
  to 
  the 
  attractions 
  of 
  neighbouring 
  atoms 
  and 
  

   the 
  repulsion 
  of 
  their 
  electrions. 
  Without 
  much 
  calculation 
  

   it 
  is 
  easy 
  to 
  see 
  that 
  generally 
  the 
  excess 
  of 
  the 
  electro- 
  

   inductive 
  permeability 
  above 
  unity 
  will 
  be 
  much 
  greater 
  than 
  

   three 
  times 
  the 
  sum 
  of 
  the 
  volumes 
  of 
  the 
  electric 
  atoms 
  per 
  

   unit 
  volume 
  of 
  space, 
  which 
  we 
  found 
  in 
  § 
  24 
  for 
  the 
  electro- 
  

   inductive 
  permeability 
  of 
  an 
  assemblage 
  of 
  single 
  atoms, 
  

   sparse 
  enough 
  to 
  produce 
  no 
  disturbance 
  by 
  mutual 
  actions. 
  

   Also 
  without 
  much 
  calculation, 
  it 
  is 
  easy 
  to 
  see 
  that 
  now 
  the 
  

   induced 
  electric 
  moment 
  will 
  not 
  be 
  in 
  simple 
  proportion 
  to 
  

  

  * 
  I 
  need 
  scarcely 
  say 
  that 
  it 
  is 
  only 
  for 
  simplicity 
  in 
  the 
  text 
  that 
  we 
  

   conveniently 
  ignore 
  Roberts-Austen's 
  admirable 
  discovery 
  of 
  the 
  inter- 
  

   diffusion 
  of 
  solid 
  gold 
  and 
  solid 
  lead, 
  found 
  after 
  a 
  piece 
  of 
  one 
  metal 
  is 
  

   allowed 
  to 
  rest 
  on 
  a 
  piece 
  of 
  the 
  other 
  for 
  several 
  weeks, 
  months, 
  or 
  

   years. 
  

  

  