﻿the 
  Vajjour-Pressure 
  of 
  Mercury. 
  

  

  795 
  

  

  Kirchhoff: 
  formula 
  will 
  express 
  vapour-pressures. 
  Thus, 
  for 
  

   temperatures 
  above 
  450° 
  we 
  have 
  : 
  — 
  

  

  Temp. 
  

  

  Formula 
  L. 
  

  

  Cailletet, 
  Colardeau, 
  

   and 
  Biviere. 
  

  

  450° 
  

   500 
  

   550 
  

   600 
  

   700 
  

  

  3,229 
  mm. 
  

  

  6,107 
  „ 
  

   10,456 
  „ 
  

   16,943 
  „ 
  

   38,109 
  „ 
  

  

  3,230 
  mm. 
  

  

  6,080 
  „ 
  

   10,488 
  „ 
  

   16,948 
  „ 
  

   38,000 
  „ 
  

  

  Table 
  IV. 
  

   Vapour-Pressure 
  of 
  Mercury 
  (in 
  mm. 
  of 
  mercury 
  at 
  0°) 
  . 
  

  

  Temp. 
  

   °C. 
  

  

  Pressure. 
  

  

  Temp. 
  

   °C. 
  

  

  Pressure. 
  

  

  Temp. 
  

  

  °C. 
  

  

  Pressure. 
  

  

  Temp. 
  

   °C, 
  

  

  Pressure. 
  

  

  15 
  

  

  •000691 
  

  

  135 
  

  

  1-52 
  

  

  255 
  

  

  86-24 
  

  

  370 
  

  

  959-2 
  

  

  20 
  

  

  •00109 
  

  

  140 
  

  

  1-89 
  

  

  260 
  

  

  97-82 
  

  

  380 
  

  

  1135 
  

  

  25 
  

  

  •00168 
  

  

  145 
  

  

  234 
  

  

  265 
  

  

  110-7 
  

  

  390 
  

  

  1337 
  

  

  30 
  

  

  •00257 
  

  

  150 
  

  

  2-88 
  

  

  270 
  

  

  124-8 
  

  

  400 
  

  

  1566 
  

  

  35 
  

  

  •00387 
  

  

  155 
  

  

  3-53 
  

  

  275 
  

  

  140-8 
  

  

  450 
  

  

  3229 
  

  

  40 
  

  

  45 
  

  

  •00574 
  

   •00840 
  

  

  160 
  

   165 
  

  

  4-30 
  

   5-218 
  

  

  280 
  

   285 
  

  

  158-4 
  

   177-9 
  

  

  

  

  

  50 
  

  

  •0122 
  

  

  170 
  

  

  6-298 
  

  

  290 
  

  

  199-3 
  

  

  

  55 
  

  

  •0174 
  

  

  175 
  

  

  7-567 
  

  

  295 
  

  

  222-8 
  

  

  Cailletet, 
  

   Colardeau, 
  & 
  

  

  Eiviere 
  

   Observations. 
  

  

  60 
  

  

  •0246 
  

  

  180 
  

  

  9-054 
  

  

  300 
  

  

  248-6 
  

  

  65 
  

  

  0344 
  

  

  185 
  

  

  10-78 
  

  

  305 
  

  

  276-9 
  

  

  70 
  

  

  •0476 
  

  

  190 
  

  

  12-80 
  

  

  310 
  

  

  307-7 
  

  

  75 
  

  

  •0652 
  

  

  195 
  

  

  15-12 
  

  

  315 
  

  

  341-4 
  

  

  80 
  

  

  •0885 
  

  

  200 
  

  

  17-81 
  

  

  320 
  

  

  378-1 
  

  

  Atmospheres. 
  

  

  85 
  

  

  •1191 
  

   •1589 
  

  

  205 
  

   210 
  

  

  20-89 
  

   24-42 
  

  

  325 
  

   330 
  

  

  418-0 
  

   461-3 
  

  

  

  90 
  

  

  500 
  

  

  8 
  

  

  95 
  

  

  •210 
  

  

  215 
  

  

  28-46 
  

  

  335 
  

  

  508-3 
  

  

  550 
  

  

  13-8 
  

  

  100 
  

  

  •276 
  

  

  220 
  

  

  3303 
  

  

  340 
  

  

  559-1 
  

  

  600 
  

  

  22-3 
  

  

  105 
  

  

  •360 
  

  

  225 
  

  

  38-23 
  

  

  345 
  

  

  614-1 
  

  

  650 
  

  

  34 
  

  

  110 
  

  

  •465 
  

  

  230 
  

  

  44-10 
  

  

  350 
  

  

  673-3 
  

  

  700 
  

  

  50 
  

  

  115 
  

  

  •597 
  

  

  235 
  

  

  5073 
  

  

  355 
  

  

  737-2 
  

  

  750 
  

  

  72 
  

  

  123 
  

  

  •761 
  

  

  240 
  

  

  58-16 
  

  

  356-7 
  

  

  760* 
  

  

  800 
  

  

  102 
  

  

  125 
  

  

  •965 
  

  

  245 
  

  

  66-50 
  

  

  360 
  

  

  805-9 
  

  

  850 
  

  

  137-5 
  

  

  130 
  

  

  1-215 
  

  

  250 
  

  

  75-83 
  

  

  365 
  

  

  879-8 
  

  

  880 
  

  

  162 
  

  

  * 
  dp/dt 
  at 
  the 
  boiling-point 
  = 
  13*6 
  mm. 
  per 
  degree. 
  

   Extrapolated 
  by 
  formula 
  M 
  : 
  

  

  10° 
  -00043, 
  5° 
  -00026, 
  0° 
  -00016. 
  

  

  Interpolation. 
  

  

  The 
  vapour-pressure 
  may 
  be 
  found 
  for 
  temperatures 
  be- 
  

   tween 
  those 
  given 
  in 
  the 
  Table 
  by 
  the 
  linear 
  interpolation 
  of 
  

  

  