,008 ME. .1. B. I.WVKs. DE. GILBEBT, wi> DB. FUGH 



suggested, to ascertain the can le - of the difference of effect, in order, if possible 



trol them. The results also point to the Insignificance of the lo t of Nitrogen in the 



form of ammonia, a supposed evil to which the attention of agricultural chemist* baa 



specially been directed in order to find means of preventing it, though nothing bt 



been done to avoid the loss, in apparently much Larger quantity, of free Nitrogen. But 



as these questions are more appropriate for consideration in ;i purely agricultural paper, 



we shall not follow them further in this place. 



Other investigations, to which we have to call attention, will throw some light upon 

 the character of the molecular forces bj which the decomposition of nitrogenous organic 

 compounds is effected under such circumstances as we have been considering. 1 

 forces might he one or both of two kinds. 



1. They might be of an oxidizing character, analogous to that of the action of chlo- 

 rine upon ammonia by which free Nitrogen is evolved. 



2. They might.be of a reducing character, similar to that of a great number of sub- 

 stances upon the oxygen-compounds of Nitrogen, by which the oxygen of the latter is 

 appropriated, and free Nitrogen given off. 



3. These two actions may operate in succession the one to the other. 



It is well known that an oxidizing action may be so intense as to deprive a nitro- 

 genous organic compound of all its carbon and hydrogen, converting it into oxygen com- 

 pounds, as is done by permanganic acid. The converse action of the transformation of 

 oxygen-compounds of Nitrogen into ammonia is also very well known. An intermediate 

 stage in either of these converse actions may give free Nitrogen. 



There can be little doubt that the Nitrogen in the organic substances which we have 

 submitted to decomposition existed in them in a condition more analogous to a hydro- 

 gen than to an oxygen compound of it. The able researches of HoFMANH into the 

 nature of compounds formed upon the ammonia type, would lead us to suppose that the 

 Nitrogen compounds upon which we have been operating are of the ammonia class. They 

 are more difficult to oxidize into nitric acid than is ammonia ; yet their transition into 

 ammonia is so easy, that it is effected in almost all the chemical changes to which they 

 are ordinarily subjected. And, since ammonias yield free Nitrogen under the influence 

 of oxidizing forces, it may be inferred that it has been under the influence of such forces 

 that Nitrogen has been set free in the cases recorded above. Pelouze has remarked* 

 that salts of nitric acid are converted into ammonia, in contact with decomposing organic 

 matter. Experiments of our own have shown that, during the decomposition of organic 

 matters in contact with nitrates, free Nitrogen is not evolved. The evolution of free 

 Nitrogen in the experiments quoted above must, therefore, be referred to the action of 

 oxidizing forces. 



The experiments next referred to bear upon these points. 



* Comptcs Ecudus, xliv. p. 118. , 



