IN GASES: HYDROGEN, CARBONIC OXIDE, AND OXYGEN. 655 
Horstmann states liis results in the following way : “ The law by which the division 
of the oxygen between the combustible gases is governed, can be expressed as folloivs : 
The ratio of the resulting water-vapour to the resulting carbonic acid is equal to the 
ratio of the unburnt hydrogen, to the unburnt carbonic oxide, multiplied by a ‘coefficient 
of affinity,' which is independent of the proportion of the combustible gases, but which 
changes with the relative mass of the oxygen added.” With equal quantities of oxygen 
the “ coefficient of affinity ” remains constant, not only when the ratio of the hydrogen 
to the carbonic oxide is altered, but also when the unburnt portion of the combustible 
gases is replaced, entirely or in part, by an indifferent gas of a similar physical con¬ 
stitution, such as nitrogen. 
The numbers from which Horstmann deduces this law are only fairly concordant. 
From the ten series of experiments made with different mixtures I have placed together, 
for the purpose of comparison, those in which nearly equal proportions of oxygen 
were taken. The first series, which Horstmann regards as incorrect, is omitted. In 
the following table the mean ratio of the oxygen to the combustible gases, the compo¬ 
sition of the mixtures, the percentage burnt, and the “ coefficient of affinity ” calculated 
from these experiments are given. 
Table XXII. —Horstmann’s Experiments. 
Mean ratio of 
oxygen to 
combustible gases. 
0 2 : (H 2 + CO,'. 
Batio of combustible 
gases before explosion. 
H 2 : CO. 
Percentage of 
combustible gases 
burnt. 
Coefficient of 
affinity. 
11 \ 
•3648 
22-0 
4-30 
•6142 
22-0 
3-81 
•3648 
251 
4-28 
•127 < 
•6142 
25-8 
4‘43 
1-2035 
25-7 
4-48 
1-0392 
24-9 
4-78 
192 
r 
•9061 
38-4 
6-35 
L 
3-0308 
38-4 
5-44 
•9061 
48-0 
5-94 
1/0392 
48-5 
5-92 
1-2035 
48-7 
5-47 
•245 < 
3-0308 
48-9 
5’86 
•6142 
49-4 
603 
•7247 
49-7 
5-67 
l 
•3648 
49-8 
5-25 
f 
•9061 
52-2 
5-09 
•268 < 
1-2035 
53-9 
5-85 
l 
3-0308 
54-7 
4-86 
r 
•9061 
63'3 
5-34 
•320 <; 
3-0308 
63-8 
4-91 
•3493 
64-1 
5 00 
i 
•3648 
6 1-3 
4-17 
