472 ON THE THEORY OF NITRIFICATION. [XX. 



60 C., in the open air, fixes in one case a small portion of ammonia 

 and in the other a little nitrous acid. Traces of a nitrite are also 

 formed in pure water under similar conditions. Sehb'nbein explains 

 all of these results by the combination of nitrogen with the elements 

 of the water, producing at the same time ammonia and nitrous acid. 

 As he has well remarked, this reaction serves to explain the absorp- 

 tion of nitrogen by vegetation, and, through the oxidation of nitrites, 

 the formation of nitrates in nature. By these elegant experiments 

 he has confirmed in a remarkable manner my theory of nitrification. 

 and of the double nature of free nitrogen. It is, however, evident 

 that since the publication of my note of March, 1861, above referred 

 to, we cannot say, with Schonbein, that the generation of nitrite of 

 ammonia from nitrogen and water is ' a most wonderful and wholly 

 unexpected thing/ (Letter from Schonbein to Faraday, Philos. 

 Magazine, June, 1862, page 467.) " Referring to the claims of Schon- 

 bein, and to my notes of March and July, 1861, the late Professor 

 Nickles wrote as follows in 1863, in his scientific correspondence for 

 the American Journal of Science ((2) XXXV. 263) : " Schonbein 

 has done justice tardily to those who have preceded him in this 

 question. Of this number is T. Steny Hunt, who, as our readers 

 may remember, long since showed that nitrite of ammonia may be 

 formed by means of nitrogen and water, and thus led the way to a 

 new theory of nitrification. This is what Bottger arrived at, who 

 first announced that nitrite of ammonia is a product of all combus- 

 tion in the air." With regard to the production of nitrite of am- 

 monia from nitrogen and water, he further adds, " this point was 

 entirely developed by Sterry Hunt." 



The publication of the above called forth a communication from 

 Professor G. C. Schaeffer in the Amer. Jour. Science for November, 

 1863, page 409, in which he draws attention to the fact that the Re- 

 port of the Smithsonian Institution for 1861 contains an essay on 

 Nitrification by Dr. B. F. Craig (written in 1856), in which the lat- 

 ter puts forth as the suggestion of Professor Schaeffer the sain.' 

 theory of nitrification as that maintained by the present writer and 

 by Schonbein ; basing it upon the view that nitrogen gas is a nitryl 

 capable of regenerating nitrite of ammonia in presence of water. 

 From this it is clear that Professor Schaeffer had independently at- 

 tained the same conclusion as myself from the conception of the. 

 dual nature of atmospheric nitrogen, which I had taught sin,. 

 He at tin- same time, as a contribution to the literature of the subject, 

 called attention to his paper in the Proceedings of the American As- 



