2£ On some new Eltctrochemkal Researches 



moisture, during or after the electrization ; but the wires . 

 were unifoimly tarnished ; and in an experiment in which 

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

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

 nearly eight cubical inches of ammonia were decomposed, 

 the weight of the oxidated matter was so minute as to he 

 scarcely sensible. By the use of a freezing mixture of 

 muriate of Jime and ice, which diminished the temperature 

 lo —15°, there was a very feeble indication given of the 

 addition of hydrometrical moisture. 



In these experiments the increase of the gas was uni- 

 formly (within a range of five parts) from 100 to 185, 

 and the hydrogen was to the nitrogen in the average pro- 

 portions of from 7374 to 2726; the proper corrections 

 being made, and the precautions before referred to being 

 taken * . 



Assuming the common estimations of the specific gra- 

 vity of ammonia, of hydrogen, and nitrogen, the con- 

 clusions which I have advanced in the Bakerian lecture for 

 1807 would be supported by these new experiments; but 

 as the moisture and oxygen visibly separated cannot be 

 conceived to be as much as -fa or T V of the weight of the 

 ammonia, I resolved to investigate, more precisely than I 

 had reason to think had been hitherto done, the specific 

 gravities of the gases concerned in their dry state ; and 

 the ve r y delicate balance belonging to the Royal Institution 

 placed the means of doing this in my power. 



Nitrogen, hydrogen, and ammonia, were dried by a long 



* Philosophical Transactions 1 809, page 459. M. Berthollet, Jim. in the 

 second volume of the Memoirs of Arcueil, has given a paper on the Uccom- 

 position of ammonia, and he enters into an examination of my idea of the 

 oxygen separated in the electrical decomposition of ammonia, which he 

 supposes I rate at 20 per cent, and at the same time he confutes some ex- 

 periments which he is pleased to attribute to me, of the combustion of 

 charcoal and iron in ammonia. His argumenis and his facts upon these 

 points appear to me perfectly conclusive; but as I never formed such an 

 opinion, as that 20 of oxygen were separated in the experiment, and never 

 imagined such results as the combustion of iron and charcoal in ammonia, 

 and never published any thing which could receive such an interpretation, 

 I shall not enter into any criticism on this part of his paper. The experi- 

 ments of this ingenious chemist on the direct decomposition of ammonia 

 seem to have been conducted with much care, except as to the circumstauce 

 of his not boiling the quicksilver; which I conceive has occasioned him to 

 over-rate the increase of volume. At *il events a loss of weight is more 

 to be expected than an increase of weight, in all very refined experiments of 

 this kind. It is possible ihat the volume may be exactly doubled, and that 

 the nitrogen may be to the hydrogen as one to three; but neither the 

 numerous experiments of IV. Henry, nor those that I have tried, establish 

 ihis; it is one of the hypothetical inferences that may be made, but it can- 

 not be regarded as an absolute fact. 



continued 



