﻿C. 
  Barus 
  — 
  Continuity 
  of 
  Solid 
  and 
  Liquid. 
  143 
  

  

  points 
  ; 
  but 
  as 
  these 
  data 
  are 
  identical 
  in 
  purport 
  with 
  those 
  

   of 
  table 
  10, 
  and 
  since 
  the 
  melting 
  volume 
  is 
  necessarily 
  less 
  

   easy 
  of 
  definition, 
  § 
  23, 
  I 
  will 
  omit 
  them 
  here. 
  

  

  Table 
  1 
  0. 
  — 
  Volumes 
  solid 
  and 
  liquid 
  at 
  the 
  solidifying 
  points, 
  varying 
  with 
  

   pressure* 
  

  

  Temperature 
  1 
  

  

  i 
  

  

  n 
  \ 
  

   in 
  | 
  

  

  IT- 
  

  

  Temperature 
  83°. 
  

  

  Temperature 
  90°. 
  

  

  Temperature 
  100°. 
  

  

  Pressure. 
  

  

  Solid 
  

   volume. 
  

  

  Pressure. 
  

   Liquid 
  

   volume. 
  

  

  Pressure. 
  

  

  Solid 
  

   volume. 
  

  

  Pressure, 
  

   Liquid 
  

   volume. 
  

  

  Pressure. 
  

  

  Solid 
  

   volume. 
  

  

  Pressure. 
  

   Liquid 
  

   volume. 
  

  

  260 
  

  

  260 
  

  

  550 
  

  

  550 
  

  

  875 
  

  

  875 
  

  

  •415 
  

  

  •534 
  

  

  •413 
  

  

  •523 
  

  

  •416 
  

  

  •510 
  

  

  320 
  

  

  320 
  

  

  555 
  

  

  555 
  

  

  920 
  

  

  920 
  

  

  •415 
  

  

  •530 
  

  

  •415 
  

  

  •527 
  

  

  •413 
  

  

  •515 
  

  

  345 
  

  

  345 
  

  

  550 
  

  

  550 
  

  

  870 
  

  

  870 
  

  

  

  

  

  

  418 
  

  

  

  

  •413 
  

  

  •510 
  

  

  

  

  

  

  900 
  

  

  900 
  

  

  

  

  

  

  

  

  

  

  •412 
  

  

  •517 
  ' 
  

  

  

  

  

  

  ---- 
  

  

  

  

  

  

  

  

  Pressure.! 
  Pressure. 
  

  

  Solid 
  Liquid 
  

   volume, 
  volume. 
  

  

  1720 
  

   •415 
  

  

  1790 
  

   ■412 
  

  

  1665 
  

   •417 
  

  

  1720 
  

  

  1720 
  

   •505 
  

   1790 
  

   •505 
  

   1665 
  

   •507 
  

   1720 
  

   •505 
  

  

  A 
  noticeable 
  feature 
  of 
  the 
  diagram 
  is 
  the 
  closer 
  accordance 
  

   of 
  the 
  three 
  groups 
  of 
  points 
  between 
  and 
  1000 
  atm., 
  during 
  

   which 
  measurements 
  steam 
  was 
  used 
  as 
  the 
  medium 
  of 
  constant 
  

   temperature, 
  as 
  compared 
  with 
  the 
  single 
  group 
  of 
  points 
  be- 
  

   tween 
  1000 
  atm. 
  and 
  2000 
  atm., 
  when 
  vapor 
  of 
  amyl 
  alcohol 
  

   was 
  used. 
  I 
  account 
  for 
  this 
  by 
  supposing 
  solidification 
  in 
  the 
  

   last 
  case 
  to 
  have 
  been 
  premature, 
  and 
  associate 
  the 
  result 
  with 
  

   insufficient 
  constancy 
  of 
  the 
  vapor 
  bath. 
  §§ 
  4, 
  20, 
  23. 
  Hence, 
  

   the 
  liquid 
  volumes 
  found 
  are 
  too 
  large. 
  There 
  may 
  also 
  have 
  

   been 
  some 
  gradual 
  change 
  of 
  the 
  constants 
  of 
  the 
  volume 
  tube, 
  

   which 
  in 
  the 
  lapse 
  of 
  time 
  became 
  appreciable. 
  §§ 
  15, 
  10. 
  

   Further 
  experiments 
  must 
  decide 
  this 
  point. 
  Regarding 
  solid 
  

   volumes 
  it 
  is 
  clear 
  that 
  no 
  device 
  can 
  define 
  them 
  as 
  closely 
  as 
  

   the 
  liquid 
  volumes 
  ; 
  indeed 
  the 
  degree 
  of 
  definition 
  attained 
  

   is 
  one 
  of 
  the 
  virtues 
  of 
  the 
  method. 
  § 
  16. 
  

  

  In 
  figure 
  3 
  I 
  have 
  therefore 
  placed 
  chief 
  reliance 
  on 
  the 
  

   water 
  points 
  (0 
  to 
  1000 
  atm.) 
  and 
  drawn 
  the 
  locus 
  accordingly. 
  

  

  26. 
  Critical 
  point. 
  — 
  The 
  area 
  enclosed 
  by 
  the 
  lines 
  ao 
  . 
  . 
  ., 
  

   and 
  bd 
  . 
  . 
  ., 
  supposing 
  b 
  and 
  c 
  eventually 
  to 
  coalesce, 
  has 
  the 
  

   same 
  signification 
  as 
  Andrews's 
  area 
  of 
  vapor 
  tensions. 
  This 
  

   would 
  also 
  be 
  true 
  of 
  the 
  similar 
  figure 
  for 
  the 
  characteristic 
  

   volumes 
  at 
  the 
  melting 
  points, 
  and 
  more 
  pointedly 
  of 
  the 
  

   figure 
  in 
  which 
  solidification 
  volumes 
  are 
  taken 
  at 
  the 
  solidi- 
  

   fying 
  points 
  and 
  fusion 
  volumes 
  at 
  the 
  melting 
  points. 
  § 
  25. 
  

   All 
  of 
  these 
  diagrams 
  point 
  out 
  the 
  probable 
  occurrence 
  of 
  a 
  

   critical 
  point 
  in 
  the 
  region 
  of 
  positive 
  pressure, 
  reached 
  in 
  the 
  

   direction 
  of 
  increasing 
  temperature, 
  at 
  which 
  point 
  solid 
  would 
  

   change 
  to 
  liquid 
  and 
  liquid 
  to 
  solid, 
  without 
  paroxysmal 
  change 
  

  

  * 
  See 
  remarks 
  on 
  table 
  11, 
  § 
  27. 
  

   Am. 
  Jour. 
  Sol— 
  Third 
  Series, 
  Yol. 
  XLII, 
  No. 
  248.- 
  

  

  -August, 
  1891. 
  

  

  