﻿120 
  Dr. 
  Veley 
  and 
  Mr. 
  Manley 
  on 
  the 
  

  

  The 
  values 
  for 
  fi 
  for 
  the 
  acids 
  of 
  lower 
  percentage 
  concen- 
  

   tration 
  (1 
  per 
  cent, 
  to 
  42 
  per 
  cent.) 
  are 
  generally 
  somewhat 
  

  

  lower 
  than 
  those 
  given 
  by 
  Kohlrausch 
  ; 
  but 
  those 
  for 
  — 
  are 
  

  

  more 
  in 
  accordance 
  with 
  those 
  calculated 
  by 
  Jones 
  * 
  from 
  the 
  

   freezing-point 
  determinations. 
  

  

  Kohlrausch 
  and 
  Hallwachs 
  f 
  have 
  pointed 
  out 
  that 
  there 
  is 
  

   an 
  undoubted 
  relation 
  between 
  the 
  contraction, 
  produced 
  even 
  

   in 
  very 
  dilute 
  solutions 
  of 
  electrolytes, 
  and 
  ionic 
  dissociation, 
  

   since 
  non-electrolytes 
  do 
  not 
  show 
  this 
  phenomenon. 
  In 
  the 
  

   present 
  instance, 
  though 
  the 
  points 
  of 
  alteration 
  of 
  direction 
  

   of 
  curvature 
  are 
  the 
  same 
  both 
  for 
  the 
  contractions 
  and 
  the 
  

   quotient 
  of 
  ionic 
  dissociation, 
  if 
  expressed 
  in 
  terms 
  of 
  per- 
  

   centages, 
  yet 
  correlation 
  of 
  the 
  two 
  phenomena 
  does 
  not 
  

   appear 
  to 
  be 
  of 
  a 
  simple 
  character. 
  

  

  Coefficients 
  of 
  Expansion. 
  

  

  Very 
  few 
  data 
  of 
  the 
  coefficients 
  of 
  expansion 
  of 
  nitric 
  acid 
  

   have 
  as 
  yet 
  been 
  recorded. 
  Kobl 
  J, 
  many 
  years 
  ago 
  as 
  a 
  

   result 
  of 
  his 
  density 
  determinations, 
  observes 
  as 
  follows 
  : 
  — 
  

   " 
  Le 
  coefficient 
  de 
  la 
  dilatation 
  de 
  l'acide 
  azotique 
  est 
  assez 
  

   eleve. 
  Ainsi 
  pour 
  l'acide 
  azotique 
  monohydrate, 
  le 
  coefficient 
  

   moyen 
  de 
  dilatation 
  entre 
  degre 
  et 
  15 
  degres 
  est 
  a 
  — 
  -001263, 
  

   c'est 
  a 
  dire 
  environs 
  trois 
  fois 
  plus 
  fort 
  que 
  celui 
  de 
  l'eau." 
  

  

  Marignac 
  gave 
  values 
  for 
  the 
  constants 
  a, 
  b, 
  and 
  c 
  in 
  the 
  

   equation 
  

  

  V,=V 
  (l 
  + 
  ^ 
  + 
  ^ 
  2 
  + 
  ^ 
  3 
  ) 
  (4) 
  

  

  for 
  a 
  few 
  samples 
  ; 
  and 
  lastly 
  Lunge 
  and 
  Rey 
  § 
  published 
  

   the 
  corrections 
  of 
  densities 
  at 
  15° 
  for 
  temperatures 
  between 
  

   13° 
  and 
  17°, 
  in 
  all 
  seventeen 
  values. 
  From 
  our 
  density 
  

   determinations 
  at 
  4°, 
  14°*2, 
  and 
  24°*2 
  corrected 
  to 
  a 
  vacuum 
  

   we 
  have 
  calculated 
  the 
  values 
  for 
  the 
  mean 
  cubic 
  expansion 
  or 
  

   values 
  of 
  a 
  from 
  the 
  equation 
  

  

  V,=V 
  4 
  (l 
  + 
  «0 
  (5) 
  

  

  These 
  values 
  expressed 
  as 
  a 
  x 
  10~ 
  6 
  are 
  given 
  in 
  the 
  following- 
  

   table. 
  

  

  * 
  Zeits. 
  f.phydkal. 
  Chem. 
  xii. 
  p. 
  623 
  (1893). 
  

  

  t 
  Gottingen 
  Nachrichten, 
  1893, 
  pp. 
  350-357. 
  Cf. 
  Drude 
  and 
  Nernst, 
  

   Zeits. 
  f. 
  physikal. 
  Chem. 
  xv. 
  p. 
  79 
  (1894). 
  

   % 
  Ann. 
  Chim. 
  Phys. 
  [4] 
  x. 
  p. 
  140. 
  

   § 
  Zeits. 
  f. 
  angewl 
  Chemie, 
  1891, 
  p. 
  167, 
  and 
  1892, 
  p. 
  10. 
  

  

  