ON EVAPORATION AND DISSOCIATION. 
G5 
The portion of ether A gave the following measurements :— 
Temperature. 
Volume. 
Specific gravity. 
Weight. 
17°95 
0-19589 
0-71627 
0-14031 
15-50 
0-19554 
0-71902 
0-14060 
16-20 
0-19571 
0-71805 
0-14053 
Mean weight.0T4048 
The volume tube was a new one, and was carefully calibrated by weighing with 
mercury. A low pressure and a high pressure gauge were employed. Where 
possible, readings on both were taken. The manometers were calibrated by 
weighing with mercury, and contained air dried over phosphorus pentoxide. 
The following corrections for volume, pressure, and temperature were applied 
For volume.—Meniscus of mercury and of liquid. 
Expansion of glass by heat. 
The expansion of the tube owing to internal pressure was not 
allowed for, as it would have been much within the errors 
of reading. 
For pressure.—Meniscus of mercury. 
Levels of mercury in volume tube and in pressure gauges. 
Difference of temperature in water-jacket at time of filling and time 
of reading. 
Deviation of air from Boyle’s Law, as determined by Amagat 
(‘ Compt. Ptend.,’vol. 99, 1884, p. 1153). 
For temperature.—Reduction of the pressure under which the liquid boiled, as 
read on the gauge, to 0° (see e Chem. Soc. Journ.,’ vol. 47, 1885, 
p. 640). 
The temperatures are those of an air-thermometer. 
Pressure 
Temperature 
Volume of 
Volume of 
Specific 
Vapour- 
Mean. 
of alcohol. 
of alcohol. 
liquid. 
1 gramme. 
gravity. 
pressure. 
* 
m ms. 
°C. 
c.cs. 
C.CS. 
nuns. 
mms. 
A' (1) 
133-7 
40 
0-20220 
1-4505 
0-68943 
921^ 
920 
922 
f 
921 
922 
(2) 
172-2 
45 
0-20398 
1-4632 
0-68342 
10851 
1085 
1086 
1085-5 
1086 
(3) 
220-0 
50 
0-20611 
1-4785 
0-67636 
12761 
1276 
1278 
> 
1277 
1278 J 
* In this, and in all other cases, the vapour-pressures were determined at widely different volumes. 
MDCCCLXXXVII.-A. K 
