﻿24 
  W. 
  P. 
  White 
  — 
  Silicate 
  Specific 
  Heats. 
  

  

  extreme 
  variation 
  of 
  1 
  to 
  7 
  and 
  the 
  attractive 
  forces 
  also 
  

   might 
  be 
  expected 
  to 
  vary 
  considerably. 
  Hence, 
  while 
  v 
  

   is 
  not 
  a 
  constant, 
  its 
  variations 
  are 
  sometimes 
  surpris- 
  

   ingly 
  small. 
  It 
  is 
  possible, 
  however, 
  that 
  the 
  compressi- 
  

   bilities, 
  that 
  is, 
  the 
  reciprocals 
  of 
  the 
  resultant 
  atom- 
  

   constraining 
  forces, 
  of 
  these 
  oxides, 
  if 
  we 
  had 
  them, 
  

   would 
  not 
  be 
  inconsistent 
  with 
  the 
  comparative 
  uni- 
  

   formity 
  in 
  v. 
  This 
  would 
  involve 
  a 
  very 
  considerable 
  

   discrepancy 
  between 
  reciprocal 
  of 
  compressibility 
  and 
  

   heat 
  of 
  formation. 
  Further 
  data, 
  especially 
  as 
  to 
  com- 
  

   pressibility, 
  would 
  seem 
  likely 
  to 
  prove 
  particularly 
  

   interesting. 
  

  

  Conclusions: 
  2. 
  Specific 
  Heats 
  at 
  High 
  Tempera- 
  

   tures. 
  

  

  The 
  discussion 
  thus 
  far 
  has 
  related 
  the 
  present 
  results 
  

   to 
  the 
  general 
  subject 
  of 
  atomic 
  heat, 
  and 
  has 
  shown 
  that 
  

   their 
  most 
  striking 
  features, 
  their 
  low 
  value 
  and 
  rapid 
  

   increase, 
  are 
  a 
  familiar 
  manifestation 
  of 
  a 
  universal 
  

   phenomenon. 
  It 
  remains 
  to 
  deal 
  with 
  such 
  things 
  as 
  are 
  

   new 
  or 
  peculiar. 
  The 
  precision 
  and 
  the 
  temperature 
  

   range 
  here 
  attained 
  both 
  appear 
  to 
  be 
  greater 
  than 
  in 
  

   previous 
  work, 
  so 
  that 
  the 
  present 
  results 
  throw 
  some 
  

   light 
  on 
  the 
  general 
  question 
  of 
  atomic 
  heats 
  at 
  rather 
  

   high 
  temperatures. 
  Above 
  700° 
  the 
  development, 
  prom- 
  

   inent 
  at 
  low 
  temperatures, 
  of 
  the 
  atomic 
  heat 
  from 
  a 
  

   zero 
  value 
  has 
  been 
  largely 
  passed 
  in 
  all 
  substances, 
  and 
  

   the 
  further 
  variation 
  in 
  specific 
  heat 
  is 
  commonly 
  

   referred 
  to 
  another 
  and 
  very 
  different 
  cause. 
  The 
  

   atomic 
  heat 
  at 
  constant 
  volume, 
  after 
  it 
  has 
  reached 
  

   normal 
  value, 
  has 
  usually 
  been 
  supposed 
  to 
  remain 
  con- 
  

   stant 
  if 
  no 
  change 
  of 
  state 
  occurs 
  ; 
  the 
  specific 
  heat 
  at 
  

   constant 
  pressure, 
  the 
  one 
  always 
  observed 
  with 
  solids, 
  

   is 
  greater 
  than 
  this 
  merely 
  by 
  reason 
  of 
  the 
  work 
  done 
  in 
  

   expanding 
  the 
  solid 
  against 
  its 
  own 
  cohesion. 
  A 
  stand- 
  

   ard 
  thermodynamic 
  formula 
  gives 
  the 
  difference 
  of 
  the 
  

  

  tW 
  ° 
  : 
  c 
  r 
  - 
  A(3a)20 
  m 
  

  

  0,-0.- 
  Kd 
  (6) 
  

  

  where 
  3a 
  is 
  the 
  cubic 
  expansion 
  coefficient, 
  K 
  the 
  (cubic) 
  

   compressibility, 
  d 
  the 
  density, 
  © 
  the 
  absolute 
  tempera- 
  

   ture, 
  and 
  A 
  a 
  dimensional 
  constant. 
  27 
  

  

  87 
  Consisting 
  of 
  1013600 
  (or 
  981000) 
  the 
  ratio 
  of 
  the 
  atmosphere 
  (or 
  

   kilogram) 
  which 
  enters 
  into 
  K, 
  to 
  the 
  dyne, 
  in 
  which 
  K 
  should 
  be 
  stated 
  

   if 
  it 
  is 
  to 
  be 
  in 
  c.g.s. 
  units, 
  divided 
  by 
  4183 
  X 
  1° 
  7 
  > 
  the 
  ratio 
  of 
  the 
  calory 
  

   to 
  the 
  erg. 
  Very 
  clearly 
  presented 
  in 
  Planck's 
  Thermodynamic 
  p. 
  118 
  of 
  

   2d 
  German 
  edition. 
  For 
  pressure 
  in 
  kg, 
  A 
  = 
  0-02345. 
  

  

  