﻿C. 
  Bar 
  us 
  — 
  Continuity 
  of 
  Solid 
  and 
  Liquid. 
  125 
  

  

  Akt. 
  XII. 
  — 
  The 
  Continuity 
  of 
  Solid 
  and 
  Liquid 
  /* 
  by 
  

   Cael 
  Barus. 
  

  

  Introductory* 
  

  

  1. 
  My 
  earlier 
  papersf 
  entered 
  somewhat 
  minutely 
  into 
  the 
  

   volume 
  thermodynamics 
  of 
  fluid 
  matter. 
  The 
  behavior 
  of 
  

   matter 
  passing 
  from 
  liquid 
  to 
  solid 
  and 
  back 
  again 
  was 
  only 
  

   incidentally^ 
  considered. 
  This 
  feature, 
  however, 
  is 
  the 
  very 
  

   one 
  which 
  gives 
  character, 
  or 
  at 
  least 
  a 
  more 
  easily 
  interpret- 
  

   able 
  character, 
  to 
  the 
  whole 
  of 
  the 
  volume 
  phenomena 
  of 
  the 
  

   substance; 
  and 
  it 
  was 
  therefore 
  reserved 
  for 
  special 
  research. 
  

  

  The 
  problem 
  may 
  be 
  looked 
  at 
  from 
  another 
  point 
  of 
  view 
  : 
  

   Let 
  it 
  be 
  required 
  to 
  find 
  the 
  relation 
  of 
  melting 
  point 
  to 
  pres- 
  

   sure. 
  My 
  results 
  have 
  long 
  since 
  shown§ 
  that 
  in 
  a 
  compre- 
  

   hensive 
  study 
  of 
  this 
  question 
  the 
  crude 
  optical 
  and 
  other 
  

   methods 
  hitherto 
  used 
  as 
  criteria 
  of 
  fusion 
  (criteria 
  which 
  have 
  

   no 
  inherent 
  relation 
  to 
  the 
  phenomenon 
  to 
  be 
  observed) 
  must 
  

   be 
  discarded. 
  In 
  their 
  stead 
  the 
  striking 
  volume 
  changes 
  

   which 
  nearly 
  always 
  accompany 
  change 
  of 
  physical 
  state, 
  in 
  a 
  

   definitely 
  constituted 
  simple 
  substance, 
  are 
  to 
  be 
  employed. 
  

  

  The 
  literature 
  [| 
  of 
  the 
  subject 
  I 
  will 
  omit 
  here, 
  since 
  the 
  

   more 
  important 
  work 
  has 
  entered 
  the 
  text-books 
  and 
  since 
  I 
  

   shall 
  probably 
  have 
  occasion 
  to 
  refer 
  to 
  it 
  elsewhere. 
  

  

  The 
  present 
  experiments 
  were 
  made 
  with 
  naphthalene 
  only. 
  

   They 
  are 
  no 
  means 
  even 
  near 
  the 
  degree 
  of 
  precision 
  of 
  which 
  

   the 
  applied 
  plan 
  of 
  research 
  admits. 
  Thus 
  far 
  my 
  chief 
  object 
  

   has 
  been 
  to 
  carry 
  the 
  method 
  quite 
  through 
  to 
  an 
  issue, 
  pre- 
  

   liminarily, 
  and 
  to 
  test 
  it 
  at 
  every 
  point. 
  The 
  data 
  are 
  suffi- 
  

   cient, 
  however, 
  to 
  show 
  that 
  the 
  procedure 
  adopted, 
  though 
  I 
  

   approached 
  it 
  with 
  diffidence, 
  can 
  be 
  brought 
  under 
  control 
  

   throughout 
  ; 
  and 
  that 
  the 
  attainable 
  accuracy 
  need 
  only 
  be 
  

   limited 
  by 
  the 
  patience, 
  skill 
  and 
  discernment 
  of 
  the 
  observer. 
  

   I 
  was 
  in 
  some 
  degree 
  surprised, 
  therefore, 
  to 
  find 
  that 
  my 
  

   method 
  led 
  to 
  new 
  results 
  at 
  the 
  outset. 
  

  

  2. 
  Earlier 
  allied 
  experiments. 
  — 
  In 
  applying 
  the 
  principle 
  of 
  

   § 
  1, 
  I 
  first 
  made 
  direct 
  volume 
  measurements 
  with 
  substances 
  

   enclosed 
  in 
  capillary 
  tubes 
  of 
  glass. 
  In 
  the 
  case 
  of 
  naphtha- 
  

  

  * 
  Geological 
  interpretations 
  are 
  in 
  the 
  hands 
  of 
  Mr. 
  Clarence 
  King, 
  by 
  whom 
  

   the 
  work, 
  as 
  a 
  whole, 
  was 
  suggested. 
  

  

  f 
  This 
  Journal, 
  III, 
  xxxviii, 
  p. 
  407, 
  1889; 
  xxxix, 
  p. 
  478, 
  1890; 
  xl, 
  p. 
  219, 
  

   1890; 
  xli, 
  p. 
  110, 
  1891. 
  Phil. 
  Mag., 
  Y, 
  xxx, 
  p. 
  338, 
  1890. 
  

  

  % 
  This 
  Journal, 
  xxxviii, 
  p. 
  408, 
  1889; 
  xxxix, 
  pp. 
  490, 
  491, 
  494, 
  1890. 
  

  

  § 
  This 
  Journal, 
  1. 
  c. 
  More 
  pointedly 
  with 
  an 
  indicatiou 
  of 
  methods 
  in 
  Phil. 
  

   Mag., 
  Y, 
  xxxi, 
  p. 
  14, 
  1891. 
  

  

  I 
  I 
  will 
  merely 
  mention 
  Sir 
  William 
  Thomson 
  (1850), 
  Bunsen 
  (1850), 
  Hopkins 
  

   (1854), 
  Mousson 
  (1858), 
  Poyntiug 
  (1881), 
  Peddie 
  (1884), 
  Amagat 
  (1887), 
  Battelli 
  

   (1887) 
  and 
  some 
  others. 
  Cf. 
  §§ 
  29, 
  30. 
  

  

  