1887.] 
Mr J. Y. Buchanan on Ice and Brines. 
141 
by increasing the pressure on pure water. Whether, or in how far, 
they agree in degree must he decided by future experiments. 
Table YII. 
Temperature 
of 
melting Ice. 
Salt dissolved. 
HC1 
NaCl 
CaCl 2 
Per cent. Cl in Solution. 
°c. 
-35 
15*26 
-30 
13-98 
• • a 
15-97 
-25 
12-60 
• • • 
14-47 
-20 
11-00 
a • a 
12-65 
-15 
9-17 
11-10 
11-29 
-10 
7-02 
8*40 
8-93 
- 5 
4-15 
4-72 
5-65 
Experiments ivitli Concentrated Solutions . — Several series of 
experiments have been made with hydrochloric acid, chloride of 
sodium, and chloride of calcium, and also with sulphuric acid. 
Table YII. gives the results, in the same form as preceding tables, 
for the chlorides. 
It will he seen that, in proportion as the solution becomes more 
concentrated, further additions of salt produce a greater effect in 
lowering the melting-point of ice, and at a temperature of — 15° C. 
equivalent weights of JSTaCl and CaCl 2 produce identical results. In 
Table YIII. the results for hydrochloric acid and sulphuric acid 
are given in terms of the percentage of hydrogen in the solution. 
Table YIII. 
Temperature of 
melting Ice. 
Acid dissolved. 
nci 
H 2 S0 4 
Per cent. H in Solution. 
- 25° C. 
0-355 
0-538 
-20 
0-310 
0-487 
-15 
0-258 
0-418 
-10 
0*198 
0-332 
- 5 
0-117 
0-205 
The temperatures given in these tables are all in terms of the same 
thermometer, which has not been verified for this part of its scale 
by comparison with a standard or with the air thermometer. 
We have thus seen that, owing to its peculiar physical properties, 
it is impossible to prepare the crystalline solid which separates from 
