SOURCES OF AMMONIA. 



peroxide of iron would be formed, and hydrogen become liberat- 

 ed. Now, if we assume that hydrogen, at the moment of its 

 liberation, is able to unite with nitrogen gas in contact with it, 

 and dissolved in water, then ammonia would be produced, and 

 would remain in union with the peroxide of iron. It is certain 

 that this explanation of the origin of ammonia in peroxide of 

 iron would be perfectly satisfactory, if it were ascertained 

 with some degree of probability that peroxide of iron has 

 had its origin by oxidation at the expense of water, and that 

 the nitrogen of air is capable of uniting with hydrogen at 

 the instant of its liberation. On this view we might suppose, 

 that although there was a limit to the formation of ammonia, 

 under former conditions, when ferruginous earth was produced, 

 that by the simultaneous occurrence of the same or of analogous 

 conditions at the present day, ammonia might still be produced. 



But the decomposition of water, by means of iron, is effected 

 under such circumstances as appear to exclude the simultaneous 

 production of ammonia. 



Iron does not decompose water at the ordinary temperatures, 

 and at higher temperatures — at the boiling point of water, for 

 example — nitrogen does not remain any longer in solution. When 

 a stream of nitrogen is made to pass along with water over iron 

 filings heated to redness, the nitrogen is again obtained unaltered 

 although it be mixed with hydrogen. It is easily explained why am- 

 monia cannot be formed in this case, for ammoniacal gas in contact 

 with iron at high temperatures, is decomposed into its constituents. 



When finely divided hydrate of peroxide of iron is placed in 

 contact with metallic iron, a decomposition of water takes place 

 at a slightly elevated temperature, and hydrogen gas is evolved, 

 while magnetic oxide of iron is produced. As hydrated peroxide 

 of iron acts as an acid in this case, we should here, as indeed 

 universally, when metals are dissolved in acids with the evolution 

 of hydrogen, obtain in the solution a salt of ammonia, if ammonia 

 had been formed. 



But hitherto the presence of ammonia under the circumstances 

 has not been detected ; and it has further been shown satisfactorily, 

 that when water holding air in solution is decomposed by a stream 

 of electricity, the hydrogen evolved is accompanied by a certain 



