282 Dr. Henry on Ducbeveiiiev's Eudiometer. 



308, I proceeded at once to subject it to the new method of 

 analysis. 



Having ascertained by a previous experiment with Volta's 

 eudiometer that 1 volumes of the gas required for saturation 

 9 volumes of oxygen, I mixed 43 measures with 43 of oxygen 

 (=41 pure), and passed a platinum ball, which had been re- 

 cently heated, into the mixture. An immediate diminution of 

 volume took place, attended with a production of heat and 

 formation of moisture. The residuary gas, cooled to the tem- 

 perature of the atmosphere, measured 43*5 volumes. Of 

 these, 4*5 were absorbed by liquid potash, indicating 4'5 cai- 

 bonic acid, equivalent to 4*5 carbonic oxide : the rest, being 

 fired in a Volta's eudiometer, with an additional quantity of 

 oxygen, gave 1 1 volumes of carbonic acid ; the diminution 

 being 22 volumes, and the oxygen consumed 22 also — circum- 

 stances which prove that 11 volumes of carbu retted hydrogen 

 were consumed by this rapid combustion. But of the loss of 

 volume first observed (viz. 86 — 43*5 = 42*5), 2*25 are due to 

 the carbonic acid formed ; and deducting this from 42*5 we 

 have 40*25, which are due to the oxygen and hydrogen, con- 

 verted into water; and 40*25 x f =26*8 shows the hydrogen 

 in the original gas. But the sum of these numbers (26*8 + 

 4'5+ll) being less by 0*7 than the volume of gas submitted 

 to analysis, we may safely consider that fraction of a measure 

 to have been nitrogen. The composition then of the mixture 

 will stand in volumes as follows : 



Hydrogen 26-8 62*32 



Carbonic oxide 4*5 10*50 



Carburetted hydrogen . . . . 11*0 25*56 



Nitrogen 07 1*62 



43*0 100-0 



On calculating what should be the specific gravity of a 

 mixture of gases in the above proportions, it was found to be 

 303; which coincides as nearly as can be expected with the 

 actual specific gravity of the gas submitted to analysis, viz. 

 308. To place the correctness of the results beyond question, 

 I mingled the gases in the above proportions, and acted on 

 the artificial mixture in the same manner as on the original 

 gas; when I had the satisfaction to find that the analytical pro- 

 cess again gave the true volumes with the most perfect cor- 

 rectness for the hydrogen and carbonic oxide, and within the 

 fraction of a measure for the carburetted hydrogen. Notwith- 

 standing this successful result, which was twice obtained, I 

 should still prefer, for the reason which has been stated, hav- 

 ing recourse to a temperature carefully regulated, for the ana- 

 lysis of similar mixtures, in all cases where the hydrogen is in 



moderate 



