22 
Proceedings of the Royal Society of Edinburgh. [Sess. 
(< Continued from page 13.) 
other times refusing to liquefy at temperatures several degrees lower than 
this temperature. These irregularities were traced to the gaseous mixture 
having separated into two portions, one rich and the other poor in carbon 
dioxide, when the pressure was reduced after liquefaction so as to convert 
the whole mixture into the gaseous state. 
Advantage was taken of this mode of separating the mixture so as to 
ascertain what change of volume occurs in the diffusion of the mixed gases 
at high pressures (Exp. 519-523, 525-531, 563-566). It thus appears that 
when carbon dioxide and nitrogen diffuse into one another at high pressures 
an increase of volume takes place, and that, on the other hand, when they 
are separated from one another there is a diminution of volume. 
The following table contains measurements of the compressibility of 
liquid carbon dioxide, up to a pressure of fully 250 atmospheres as 
measured on the hydrogen manometer. 
Compressibility of Liquid Carbon Dioxide, April 15-18, 1870. 
Number in 
Notebook 16, 
Volume VIII. 
Hydrogen. 
Carbon Dioxide. 
Difference 
of Levels. 
Tempera- 
ture. 
Column 
Length. 
V olume. 
Pressure 
in Atmo- 
spheres. 
Tempera- 
ture. 
Column 
Length. 
Volume. 
320" 
0° 
14-55 
358-1 
0-3052 ±-0012 
0-006029 
1 
55-0 
12-73 
46-64 
0-0007717 
287-0 - 
321 
14-51 
272-5 
4580 
73-6 
12-81 
45-09 
7465 
203-0 - 
322 
14-51 
273-3 
4595 
73-3 
12-73 
45-11 
7472 
203-7 - 
323 
14-53 
206-1 
3466 
99-0 
12-62 
43'52 
7193 
138-1- 
324 
14*56 
154-0 
2602 
135-2 
12-77 
42'24 
6987 
87'4- 
325" 
14-38 
116-4 
1977 
183-6 
12-82 
40-82 
6753 
5P3- 
326 
14-48 
117-6 
1996 
181-5 
12-73 
40-94 
6777 
52-6- 
327 
14-48 
87-1 
1480 
256-9 
12-75 
39-45 
6528 
23-8- 
328 
14-33 
88-6 
1505 
251-8 
12-92 
39-48 
6533 
25-4- 
328 bis 
14-36 
87-0 
1478 
257*4 
12-68 
39-39 
6515 
24-0- 
328 iris 
14-34 
87-3 
1483 
254-9 
12-68 
39-38 
6513 
24-3- 
{Issued separately December 1, 1909.) 
