﻿AND 
  ITS 
  CONNECTION 
  WITH 
  THE 
  THEORY 
  OF 
  HEAT. 
  433 
  

  

  fore, 
  for 
  every 
  substance 
  in 
  nature, 
  the 
  mean 
  specific 
  gravity 
  of 
  the 
  atomic 
  atmosphere 
  

   in 
  the 
  theoretical 
  state 
  of 
  perfect 
  gas 
  is 
  inversely 
  proportional 
  to 
  the 
  specific 
  elasticity 
  

   of 
  that 
  atmosphere. 
  

  

  Real 
  specific 
  heat 
  may 
  also 
  be 
  thus 
  expressed 
  : 
  — 
  

  

  »-Vi£ 
  (2o.) 
  

  

  'o 
  z 
  M 
  

  

  , 
  . 
  , 
  V 
  n 
  , 
  1 
  . 
  o 
  A 
  kU 
  , 
  3/fcM 
  1 
  

  

  in 
  which 
  -fi 
  corresponds 
  to 
  q^i 
  m 
  my 
  former 
  papers, 
  and 
  y- 
  to 
  2 
  or 
  ^ 
  ■ 
  

  

  The 
  latter 
  factor 
  appears 
  to 
  depend 
  on 
  the 
  chemical 
  constitution 
  of 
  the 
  sub- 
  

   stance, 
  being 
  the 
  same 
  for 
  all 
  simple 
  gases. 
  

  

  (8.) 
  Total 
  Pressure 
  of 
  Substances 
  in 
  general, 
  expressed 
  in 
  terms 
  of 
  temperature. 
  

   In 
  equation 
  (9) 
  let 
  - 
  be 
  put 
  for 
  6 
  : 
  then 
  

  

  ■^ 
  «-rx 
  - 
  /rr> 
  Jl 
  U 
  T 
  „ 
  f 
  _, 
  K 
  G' 
  K 
  2 
  G" 
  . 
  "I 
  

  

  P= 
  J0 
  + 
  /(V) 
  = 
  /-(V) 
  + 
  a 
  ^ 
  t 
  G 
  1 
  --(G 
  1 
  -L 
  + 
  _J--&e. 
  j 
  

  

  =/(V)+^f 
  {l-^-^-^-&c.} 
  . 
  . 
  (21.) 
  

  

  where 
  

  

  A 
  — 
  -A 
  — 
  — 
  fCi 
  ' 
  2 
  _ 
  Ct 
  "\ 
  

  

  A 
  s 
  = 
  - 
  gpr 
  (<V 
  3 
  - 
  2 
  G/ 
  G/' 
  + 
  G/") 
  ; 
  &c. 
  

  

  1 
  

  

  This 
  formula 
  is 
  identical 
  with 
  that 
  which 
  I 
  employed 
  in 
  my 
  former 
  paper, 
  to 
  

   represent 
  the 
  pressure 
  of 
  an 
  imperfect 
  gas, 
  and 
  which 
  I 
  found 
  to 
  agree 
  with 
  M. 
  

   Regnaults 
  experiments, 
  when 
  the 
  coefficients 
  A 
  and 
  the 
  function/ 
  (V) 
  had 
  been 
  

   calculated 
  empirically. 
  

  

  Section 
  Second. 
  — 
  Relations 
  between 
  Heat 
  and 
  Expansive 
  Power. 
  

  

  (9.) 
  Variations 
  of 
  Sensible 
  and 
  Latent 
  Heat 
  : 
  Fundamental 
  Equation 
  of 
  the 
  

   Theory. 
  — 
  If 
  the 
  forms, 
  positions, 
  and 
  magnitudes 
  of 
  the 
  paths 
  described 
  by 
  the 
  

   revolving 
  particles 
  of 
  the 
  atomic 
  atmospheres 
  be 
  changed, 
  whether 
  by 
  a 
  variation 
  

   of 
  mean 
  density, 
  or 
  by 
  a 
  variation 
  of 
  temperature, 
  an 
  increase 
  or 
  diminution 
  of 
  

   the 
  vis- 
  viva 
  of 
  their 
  motion, 
  that 
  is 
  to 
  say, 
  of 
  the 
  heat 
  of 
  the 
  body, 
  will 
  take 
  place 
  

   in 
  virtue 
  of 
  that 
  change 
  of 
  the 
  paths 
  of 
  motion 
  ; 
  an 
  increase 
  when 
  they 
  are 
  con- 
  

   tracted, 
  and 
  a 
  diminution 
  when 
  they 
  are 
  dilated. 
  

  

  Let 
  8 
  . 
  Q, 
  represent, 
  when 
  positive, 
  the 
  indefinitely 
  small 
  quantity 
  of 
  heat 
  which 
  

   must 
  be 
  communicated 
  to 
  unity 
  of 
  weight 
  of 
  a 
  substance, 
  and 
  when 
  negative, 
  

   that 
  which 
  must 
  be 
  abstracted 
  from 
  it, 
  in 
  order 
  to 
  produce 
  the 
  indefinitely 
  small 
  

   variation 
  of 
  temperature 
  8 
  t 
  simultaneously 
  with 
  the 
  indefinitely 
  small 
  variation 
  

  

  VOL. 
  XX. 
  PART 
  III. 
  6 
  A 
  

  

  