3 70 E^eriments on Ammonia. 



duction of water by the same operation ; a fact, which would 

 be scarcely less satisfactory in establishing oxygen to be 

 one of its constituents, than the actual separation of oxy- 

 gen iras. The most careful observation of ammonia, during 

 and "after the agency of electricity', does not discover the 

 smallest perceptible quantity of moisture. In order, there- 

 fore, to subject the gvis to a satisfactory test, I had recourse 

 to the following contrivance : — Ammoniacal gas, I had pre- 

 viously found, may be so far desiccated by exposure to 

 caustic potash as to show no traces of condensed moisture, 

 on the inner surface of a thin glass vessel containing it, 

 when exposed to a cold of 0° Fahrenheit; though the re- 

 cent gas, by the same treatment, is made to deposit water 

 in the state of a thin film of ice. A glass globe, of the 

 capacity of between two and three cubical inches, was filled 

 with gaseous ammonia, which was then dried by sticks of 

 pure potash, fastened to pieces of sieel wire, so that they 

 could be withdrawn after having exerted their full action. 

 This point of dryness was ascertained by applying ether, or 

 a mixture of snow and salt, to the outside of the globe. 

 By means of a peculiar apparatus, the gas was next strongly 

 electrified, and the cooling power was again applied to the 

 outer surface of the globe. 



In the first trials that were made with this apparatus 

 water certainly seemed to have been formed by the elec- 

 trization of the alkaline gas; for the same portion of gas, 

 which was not affected by a freezing mixture before the 

 process, gave evident signs of condensed moisture when 

 the cooling power was applied after long continued elec- 

 trization. The appearance was not only quite satisfactory 

 to myself, but to Mr. Dalton, and several other chemical 

 friends, to whom I showed the experiment. Finding, 

 however, that the appearance varied as to its degree, I was 

 induced to repeat the process with redoubled precaution ; 

 filling the globe, previously heated, with hot mercury, and 

 drying, not only the quicksilver, but the iron cistern which 

 contained it, by exposure to long continued heat. The 

 electrified gas now betrayed no signs of moisture on the 

 application of a temperature 20° of Fahrenheit, and gave 

 only the smallest perceptible traces by a cold of 0'^ or a 

 tew degrees below. I cannot help suspecting, therefore, 

 that the moisture manifested in the earlier experiments was 

 derived from the mercurv or fVom some extraneous source, 

 and was not generated by the action of electricity *. 



* It may he objected, I am aware, that J»s the gfases produced from am- 

 monui are nearly double its original bulk, they may hu!d in combiuatioit 



9nj 



