PHYSICAL CHARACTERS OR MIXTURES AND SOLUTIONS. 
339 
columns 2 and 3 the volumes of water and methylic alcohol respectively contained, at 
a temperature of 10° C., in 100 volumes of a spirit of the strength given in column 1. 
Columns 4 and 5 give the combined volumes of the two, before and after mixture 
respectively ; and, lastly, column G gives the differences between 4 and 5, thus showing 
the amount of contraction having taken place in the formation of 100 volumes of the 
various mixtures. The figures in this Table are calculated from those given in Table VI. 
By help of this Table the numbers contained in column 4, Table VII., have been calcu- 
lated thus : — • 
Let w be the volume per cent, of water contained in the mixture at 10' C., 
m the volume percent, of methylic alcohol present at the same temperature, and 
C the amount of contraction which has taken place in the formation of 100 
volumes of this mixture at 10° C., 
Then 100 volumes of this mixture at 10° C. would occupy at 20° 
w x 100-154 mx 10U290 
100 ‘ Too 
volumes, on the assumption that the expansion is proportioned to the volumes of the 
constituents. 
The capacity of the specific-gravity bottle employed was at 10° C. - 545-4985 cub. 
centims., at 20° C. = 545-G585 cub. centims. 
This bottle was brought to the exact temperature desired by immersion in a water- 
bath of special construction, for details of which see Philosophical Transactions, 18G9, 
p. G08. 
Table VI. 
Per cent, of methylic 
alcohol, by weight. 
Specific gravity 
at 10°C. 
Specific gravity 
at 20° C. 
1 Specific gravity at 
10 3 C., calculated. 
Difference. 
0 
99973 
99819 
10 
98632 
98384 
97762 
+ 870 
20 
97478 
97080 
95622 
1 856 
30 
96222 
95675 
93573 
2649 
40 
94729 
94054 
91611 
3118 
50 
92991 
92205 
89727 
3264 
60 
91048 
90207 
87923 
3125 
70 
88933 
88035 
86188 
2745 
80 
86598 
85655 
84520 
2078 
90 
84054 
83079 
82916 
1138 
100 
81371 
80334 
3 a 
MDCCCLXXII. 
