﻿490 
  Prof. 
  Lyle 
  and 
  Mr. 
  Hosking 
  on 
  tlie 
  Conductivity 
  

  

  The 
  volume 
  of 
  solution 
  in 
  the 
  dilatometer 
  at 
  any 
  tem- 
  

   perature 
  t° 
  C. 
  was 
  given 
  by 
  

  

  V*= 
  (5-030 
  + 
  n 
  x 
  -001296) 
  (1+0-00O0287*) 
  . 
  c.c, 
  

  

  where 
  n 
  was 
  the 
  scale-reading. 
  With 
  this 
  instrument, 
  

   values 
  for 
  the 
  density 
  of 
  water 
  were 
  obtained 
  agreeing 
  with 
  

   the 
  true 
  values 
  to 
  within 
  -01 
  per 
  cent, 
  between 
  temperatures 
  

   0° 
  and 
  90° 
  C. 
  which 
  was 
  sufficiently 
  accurate 
  for 
  our 
  purpose. 
  

  

  Fig. 
  2. 
  

   "Dilatometer 
  

  

  Pig. 
  3. 
  

   Electrolytic 
  Cell. 
  

  

  d 
  I 
  

  

  The 
  electrolytic 
  cell 
  was 
  constructed 
  wholly 
  of 
  glass 
  

   (fig. 
  3), 
  and 
  the 
  electrodes 
  could 
  always 
  be 
  fixed 
  at 
  exactly 
  

   the 
  same 
  place, 
  for 
  when 
  they 
  were 
  in 
  position 
  they 
  rested 
  

   on 
  the 
  open 
  ends 
  of 
  the 
  tube 
  containing 
  the 
  solution, 
  these 
  

   ends 
  being 
  in 
  the 
  centre 
  of 
  pear-shaped 
  bulbs 
  which 
  connected 
  

   with 
  wide 
  tubes 
  passing 
  through 
  the 
  cover 
  of 
  the 
  bath, 
  and 
  

   supported 
  by 
  it. 
  Sufficient 
  solution 
  was 
  used 
  to: 
  fill 
  the 
  cell 
  

   to 
  the 
  top 
  of 
  the 
  bulbs. 
  The 
  wires 
  leading 
  to 
  the 
  electrodes 
  

  

  