ON EVAPORATION AND DISSOCIATION. 
115 
Series V. 
Pressure. 
Temperature. 
Pressure. 
Temperature. 
Pressure. 
Temperature. 
millims. 
O 
millims. 
O 
millims. 
O 
717-9 
117-15 
4603 
103-3 
242-1 
84'6 
657-5 
114-1 
425-2 
100-6 
228-0 
83-4 
642-6 
113-4 
396-3 
98-6 
215-2 
81-65 
623-8 
112-4 
376-4 
97-4 
199-5 
79-8 
587-1 
110-4 
344-3 
94-5 
177-3 
76-4 
540-0 
107-45 
307-9 
91-4 
127-5 
68-5 
501-8 
105-45 
267-8 
87-5 
87-6 
59-6 
55-6 
49-65 
The shortness of series III. and IV. is accounted for by the fact that they consist of 
the higher numbers of series which have been elsewhere given. The results by both 
methods are shown in Plate 2. 
§ 74. It was thought possible that the hydrochloride of ethylamine, and that chlorine 
hydrate might yield serviceable results. The former gave off a permanent gas, and 
grew pasty when heated; the temperature rose steadily to above 300° with no sign of 
a check. 
The chlorine hydrate, prepared by bringing a thermometer-bulb covered with cotton¬ 
wool, and soaked with water, in contact with chlorine at a low temperature, melted 
suddenly when the pressure was lowered, with rapid evolution of chlorine, while the 
temperature rose to 0°. This unusual behaviour perhaps deserves further investiga¬ 
tion,* but as it did not come under our programme, it was not further followed. 
* (Since -writing the above, the matter lias been made the subject of experiment by H. Le Chatelier, 
“ Comptes Rendus,” 99, p. 1074; he finds that solid chlorine hydrate lias a higher vapour-pressure than 
the liquid hydrate, if the latter exists, and is not a mere solution of chlorine in water. It may be 
remembered that similar results with chloral ethyl- and methyl-alcoholates are described by us in § 25). 
