gaseous mixtures , and its application to their analysis. 28 1 
When equal volumes of carbonic oxide and hydrogen 
gases, mixed with oxygen sufficient to saturate only one of 
them, were exposed in a glass tube to the flame of a spirit 
lamp, without the presence of the sponge, till the tube began 
to soften, the combination of the gases was effected without 
explosion, and was merely indicated by a diminution of vo- 
lume, and an oscillatory motion of the mercury in the tube. 
At the close of the experiment, out of twenty volumes of 
oxygen, eight were found to have united v/ith the carbonic 
oxide, and twelve with the hydrogen, proportions which do 
not materially differ from the results of the first experiment 
in the foregoing Table. At high temperature, then, the 
attraction of hydrogen for oxygen appears to exceed that of 
carbonic oxide for oxygen : at lower temperatures, especially 
when the gases are in contact with the platinum sponge, the 
reverse takes place, and the affinity of carbonic oxide for 
oxygen prevails. 
Extending the comparison to the attraction of olefiant and 
hydrogen gases for oxygen at a red heat, I found that when 
six volumes of olefiant, six of hydrogen, and three of oxygen 
were heated by a spirit lamp till the tube softened, a silent 
combination took plate as before ; all the oxygen was con- 
sumed ; but only half a volume had been expended in form- 
ing carbonic acid, which indicates the decomposition of only 
one quarter of a volume of olefiant gas. On attempting a 
similar comparison between carbonic oxide and olefiant gas, 
by heating them with oxygen in the same proportions, the 
mixture exploded as soon as the glass became red hot, and 
burst the tube. 
The property inherent in certain gases, of retarding the 
mdcccxxiv. O o 
