82 UOW CROPS FEED. 



command for experimental study, will estaldish or disprove 

 them by suitable investigations. 



lie believes, from the exi^tino; evidence, that free nitro- 

 gen can, in no case, unite directly with water, but in the 

 conditions of all the foregoing experiments, it enters com- 

 bination by tlie action of ozone^ as Schonbein formerly 

 maintain.ed and was the first to suggest. 



We have already recounted the evidence that goes to 

 show tlie formation of ozone in all cases of oxidation, both 

 at high and low temperatures, p. 67. 



In Zabelin's experiments we may suppose that ozone 

 was formed by the oxidation of the cellulose (linen and 

 paper) he emiiloyed. In Schimbein's experiments, where 

 paper or linen was not employed, tlie dust of the air may 

 have supplied the organic matters. 



The first result of the oxidation of nitrogen is nitrous 

 acid alone (at least Schonbein and Bohlig detected no ni- 

 tric acid), when the combustion is complete, as in case of 

 hydrogen, or when organic matters are excluded from the 

 experiment. Nitric acid is a product of the subsequent 

 oxidation of nitrous acid. When organic matters exist in 

 the product of combustion, as when alcohol burns in a 

 heated apparatus yielding water having a yellowish color, 

 it is probable that niti'ous acid is formed, but is afterward 

 reduced to ammonia, as has been already explained, p. 74. 



Zabelin, in the article before cited, refers to Schonbein 

 as authority for the fact that various organic bodies, viz., 

 all the vegetable and animal albuminoids, gelatine, and 

 most of the carbohydrates, especially starch, glucose, and 

 milk-sugar, reduce nitrites to ammonia., and ultimately to 

 nitrogen ; and although we have not been able to find such 

 a statement in those of Schonbein's papers to which we 

 have had access, it is entirely credible and in accordan«e 

 with numerous analogies. 



If, as thus appears extremely probable, ozone is devel- 

 oped in all cases of oxidavion, both rapid and slow, then 



