1890-91.] Prof. Tait on Isothermals of Ethyl Oxide . 
265 
Note on the Isothermals of Ethyl Oxide. By Prof. Tait. 
(Read July 6, 1891.) 
The first three pressure-columns of the following little table were 
constructed from the elaborate data given by Drs Ramsay and Young 
in their important paper “ On Evaporation and Dissociation,” Part 
IV. (Phil. Mag., May 1887). They give, in metres of mercury, the 
pressures required to confine one gramme of oxide of ethyl to various 
specified numbers of cubic centimetres, at temperatures near to that 
of the critical point. 
V 
193°-8 
A 
B 
C 
2 
73. 
72-9 
2-3 
38-6 
38-55 
38-3 
2-4 
34. 
34-3 
3443 
34-16 
2-5 
31-2 
31-3 
31-53 
31-55 
2-75 
28- 
28-1 
28-24 
28-41 
3 
. . . 
27-7 
27-42 
27-45 
3-3 
27-2 + 
27-19 
27-3 
3-7 
27-2 
27-19 
27-2 
4 
... 
tsD 
Y* 
LO 
27-20 
27-2 
5 
27- 
271 
27-12 
27-1 
6 
26-6 
26-7 
26-80 
26-46 
7 
25-9 
25-9 
26-00 
25-6 
10 
22-9 
22-9 
22-89 
22-86 
15 
18-3 
18-4 
18-26 
18-0 
20 
15-0 
15-0 
14-97 
14-8 
50 
7- 
7- 
7-01 
7-02 
100 
37 
3-69 
3.75 
300 
1-27. 
1-28 
1-32 
The values in the second column are taken directly from the paper 
referred to (Table I.), in which 193°*8 C. is regarded by the Authors 
as the critical temperature. Those in column A were calculated 
for temperature 194° C. from the pressures given in the same table 
for 195° C. and 200° C. (occasionally 210° or 220° C.). Those in 
column B were calculated, also for 194° C., from Table II. of Drs 
Ramsay and Young, which contains their “smoothed” values of 
