EADIATION OF HEAT BY GASES AND VAPOUES. 
Subsequent observations lead me to believe that the absorption by chloroform is a 
little higher than that given in the above Table. 
Table XVII. — Alcohol. 
Unit-measure ^ a cubic inch. 
Absorption. 
of measures. 
Observed. 
Calculated. 
1 
4-0 
4-0 
o 
7-2 
8-0 
O 
O 
10-5 
12-0 
4 
14-0 
16-0 
0 
19-0 
20-0 
6 
23-0 
24-0 
7 
28-5 
28-0 
8 
32-0 
32-0 
9 
37-5 
36-0 
10 
41-5 
40-0 
11 
45-8 
44-0 
12 
48-0 
48-0 
13 
50-4 
52-0 
14 
53-5 
56-0 
15 
55-8 
60-0 
By mercurial gauge. 
Tension. 
Deflection. 
Absorption. 
^ inch 
60 
157 
1 inch 
not practicable. 
The difference between the measurements when equal tensions and when equal 
volumes at the maximum density are made use of, is here strikingly exhibited. 
In the case of alcohol I was obliged to resort to a unit-measure of a cubic inch 
to obtain an effect about equal to that produced by benzol with a measure possessing 
only 1 ^ 0 of a cubic inch in capacity; and yet for equal tensions of 0-5 of an inch 
alcohol cuts off precisely twice as much heat as benzol. There is also an enormous 
difference between alcohol and sulphuric ether when equal measures at the maximum 
density are compared ; but to bring the alcohol and ether vapours up to a common 
tension, the density of the former must be many times augmented. Hence it follows 
that when ecpud tensions of these two substances are compared, the difference between 
them diminishes considerably. Similar observations apply to many of the substances 
whose deportment is recorded in the foregoing Tables ; to the iodide and chloride of 
amyl, for exnmple, and to the propionate of ethyl. Indeed it is not unlikely that with 
