364 Experiments on the Nature of [Nov. 



other side, azote is considered a»s an oxide, and the nitrous acid 

 be represented by N + 5 O, the greatest quantity of lead that 

 can be dissolved by 100 of nitrate of lead will be 11 1*45 ; while 

 experiment shows ihat it can dissolve 130. I think, then, that 

 in the present state of our knowledge what I have stated may be 

 considered as a decisive proof that nitrous acid is composed of 

 1 volume (atom or proportion) of nitric and 4 volumes of 

 oxygen ; and that it may be represented by N + 4 O. 



Let us now examine what the combinations may be, called 

 nitrous acid by Gay-Lussac and Davy. It is well known that 

 the more powerful acids can hardly ever be produced without the 

 presence of some oxide to serve them as a base. This is the 

 case with sulphuric, nitric, muriatic acids, &c. I have endea- 

 voured to prove, likewise, that the oxides of the same radicle 

 often combine together in the same manner as oxides with diffe- 

 rent radicles. If in the experiment of condensing oxygen gas 

 by means cf nitrous gas, nitrous acid may serve as a base for 

 nitric acid, it is obvious that the two acids must combine in such 

 proportions that each shall contain equal quantities of oxygen, 

 or that the one shall contain 2, 3, &c. times as much oxygen as 

 the other. If we suppose that the acids combine in such a pro- 

 portion that both contain equal quantities of oxygen, this com- 

 bination will consist of 2 volumes of nitrous gas, and 09, or 

 almost a volume, of oxygen gas. This, in all probability, is the 

 nitrous acid of Sir Humphry Davy. If to the preceding mixture 

 we add another volume of nitrous gas, we shall have the nitrous 

 acid of Gay-Lussac, in which the nitric acid contains twice as 

 much oxygen as the nitrous acid. 



Let us now turn our attention to ammonia. We know that 

 its alkaline nature indicates the existence of oxygen in it ; for, 

 on the contrary supposition, one of the strongest saline bases 

 would be an exception to the general rule, and would fail in its 

 analogy to bodies of a similar nature. I have shown that am- 

 monia, to judge from the quantity of it necessary to neutralise an 

 acid, must contain about 46-88 per cent, of oxygen: but we have 

 seen that the combinations which nitric acid forms with saline 

 bases would not be proportional to the laws of chemical combi- 

 nations, unless azote contained oxygen; and as azote is one of 

 the constituents of ammonia, we see in consequence that the 

 presence of oxygen in that alkali is rendered very probable, or 

 rather is proved. 



When 1 first convinced myself that ammonia must contain 

 oxygen, I considered it as composed of azote, hydrogen, and 

 oxygen, according to the experiments of Sir H. Davy. Some 

 time after, the experiments of Berthollet, jun. of Henry, and 

 Davy, proved that ammonia, when decomposed, furnishes a 

 quantity of azote and hydrogen equal in weight to the portion of 



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