Experiments on Ammonia. 375 



exsy to calculate the quantity of hydrogen In the saturation 

 of which it has been employed ; for, when no nitrous acid 

 has been formed, the hydrogen will be pretty exactly double 

 in volume the oxysren which has been expended. 



These general observations will tend to render the fol- 

 lowing experiments more intelligible. They may be di- 

 vided into two classes ; 1st, those in which ammonia was 

 fired with an excessive proportion of oxygen ; and 2dly, 

 those in which the oxygen used in the first combustion was 

 insufficient, or barely adequate, to saturate the whole hy- 

 drogen of the alkali. 



I. Decomposition of Ammonia ly an Excess of Oxygen Gas. 

 Twenty-two measures and a third of ammonia were 

 mixed with 44 j oxygen containing 43 of pure gas. The 

 total 67 became 34 when exploded. Water did not pro- 

 duce any further diminution, but sitlphuret of lime left only 

 8 measures. Now, 34- — 8 = 26 shows the" quantity of 

 oxygen gas which escaped condensation; and this, de- 

 ducted from the origmal quantity (43), give^ 1 7 measures 

 for the amount of the oxygen expended. The last number 

 17, being multiplied by 2, gives 34 for the hydrogen ap- 

 parently consumed. The final residue 8 — r66 (the ni- 

 trogen introduced by the oxygen gas) = 6*34 is the nitro- 

 gen obtained from 22-^- of amni'juia; and if to this the hy- 

 drogen be added, 40-34 measures of permanent gas will be 

 the total result. Hence 100 measures of the gas produci- 

 ble from ammonia, should contani 84*29 hydrogen and 

 15'71 nitrogen; numbers too remote from those, wliich 

 have been already assigned, to be considered even as ap- 

 proximations to the truth. The error arises from the com- 

 bination of oxygen, during combustion, not only with the 

 hydrogen, but with the nitrogen of the alkali, the latter of 

 which consequently appears deficient, and tlie former pro- 

 portionably in excess. 



Fre(juent repetitions of this combustion, with a consi- 

 derable excess of oxygen gas, continued to give a deficient 

 proportion of nitrogen ; and as no accurate conclusions 

 can be drawn from experiments of this kind, J shall pro- 

 ceed to those of the second class. 



[To lie contieued.] 



Aa4 \Ai.Ob. 



