1825.] Jinelj/ divided Platinum on Gaseous Mixtures. 421 



7. Mixtures of Hydrogen, Carhuretted Hydrogen, and Carbonic 



Oxide with Oxygen. 



In mixtures of these gases, it is of little consequence whether 

 the oxvcren be sufficient for the hydrogen and cai^bonic oxide 

 only, ox\e adequate to the saturation of all three. The circum- 

 stance, which has the greatest influence on the results of expos- 

 ing such mixtures to the sponge, is the proportion which the 

 simple hydrogen bears to the other gases, and especially to the 

 carbonic oxide ; for in order that there may be any immediate 

 action, the hydrogen should exceed the other gas in volume, in 

 that case the hydrogen is converted into water, and the carbonic 

 oxide into carbonic acid ; but the carburetted hydrogen, unless 

 the excess of hydrogen be very considerable, remains unaltered. 

 If the proportion of hydrogen be so small, that no immediate 

 action is excited by the sponge, the ingredients of the mixture 

 nevertheless act slowly upon each other; and after a few days, 

 the whole of the hydrogen and carbonic oxide are found to have 

 united with oxygen, and the carburetted hydrogen to remain ot 

 its original volume. 



8. Mixtures of Hydrogen, Carbonic Oxide, and Olefiant Gases 



with Oxygen. 



When the oxygen, in a mixture of these gases, is sufficient to 

 saturate the first two only, and the proportion of hydrogen is so 

 adjusted that the action of the sponge is not very energetic the 

 hydiwen and carbonic oxide only are acted upon; but it the 

 diminution of volume, which the sponge produces, be rapid and 

 considerable, part of the olefiant gas is converted into water and 

 carbonic acid. This eff^ect on olefiant gas takes place still more 

 readily, if the oxygen present be adequate to the saturation ot all 

 three combustible gases. . 



It is remarkable, that if to a mixture of hydrogen, carbonic 

 oxide, and oxygen, in such proportions that the spong-e vyould 

 act rapidly in producing combination, olefiant gas be added, the 

 action of the gases on each other is suspended. Ihus 20 mea- 

 sures of carbonic oxide, 31 of hydrogen, and 28 of oxygen, were 

 instantly acted upon by the sponge; but the addition of 20 

 measures of olefiant gas to a similar mixture entirely suspended 

 its efficieocv. By standing fourteen days, rather more than halt 

 the carbonic oxide was acidified, and about one-twelfth of the 

 hydrogen was changed into water, but the olefiant gas remained 

 unaltered. 



9. Mixtures of lIi/dro(ren, Carbonic Oxide, Carburetted Hydro- 



gen, and Olefiant Gases with Oxygen. 

 In mixtures of these four gases with oxygen, it was found, 

 by varying the proportion of hydrogen, that hydrogen and 



