50 OK KITROOEN AND AMMftNIA. 



ratus (of which a figure is attached to this paper,) in which 

 nothing was present but the gas, the metals for conveying 

 the electricity, and glass. The ammonia was introduced 

 by a stopcock, which was cleared of common air, into a 

 globe that was exhausted, after being filled two or three 

 times with ammonia: the gas that was used was absolutely 

 pure, Jhe decomposition was performed without any possi- 

 bility of change in the volume of the elastic -matter, and 

 the apparatus was such, that the gas could be exposed to a 

 freezing mixture, and the whole weighed before and after 

 the experiment. 

 Reason of The object in keeping the volume the same during the 



keeping the decomposition was to produce the condensation of any 

 the^same. aqueous vapour, which, if formed in small quantity in the 

 operation, (on the theory of the mechanical diffusion of va- 

 pour in gasses,) might, in the common case of decomposi- 

 tion, under the usual pressure, be in quantity nearly twice 

 as much in thehidrogen and nitrogen, as in the ammonia, 

 J?esults, In all instances it was found, that there was no loss of 



weight of the apparatus, nor was there any deposition of 

 moisture, during or after the electrization; but the wires 

 were uniformly tarnished; and in an experiment in which 

 surfaces of brass were used, a small quarrtity of olive co- 

 loured matter formed on the metal ; but though in this case 

 nearly 8 cubical inches of ammonia were decomposed, the 

 weight of the oxidated matter was so minute as to be scarcely 

 sensible. By tlie use of a freezing mixture of muriate of 

 lime and icr, which diminished the temperature to — 15% 

 there was a very feeble indication given of the addition of 

 hygrometrical moisture. 



In these experiments the increase of the gas was uniform- 

 ly (within a range of five parts) from 100 to 185, and the 

 hidrogen was to the nitrogen in the average proportions of 

 from 73 or 74 to 27 or 2() ; the proper corrections being 

 made and the precautions before referred to being taken*. 



Assuming 



Borthollet'sex- * PhiloBOphical Transactions, 1809, pagf» 459 [Journal, vol. XXV, 

 perinoents «n p, 143, 144]. Mr. BerlhoUct, jun., in the second rolume of the Me- 

 thedecompo moirs of Arcueil, has given a paper on the decomposition of ammonia, 

 mouia ' *°*^ ^^ enters into an examination of my idea of the oxijen, separated 



