AGRICULTURE AND RURAL ECONOMY. 547 



and from ammonia both of which are oxidized in the soil 

 and, in small part probably, from the air. How nitrification 

 (the oxidation of nitrogenous matters) takes place is one of 

 the most interesting problems of agricultural chemistry. 



Nitrification by Organized Ferments. 



We noted last year some experiments by Schloessing and 

 Miintz, which showed that the oxidation of nitrogen com- 

 pounds may be induced by organized ferments, and that it is 

 probably a function of a low form of vegetable life, though 

 the experimenters were careful not to say that this is the only 

 cause of nitrification. They further stated that this theory 

 was regarded as probable by Pasteur as far back as in 1862. 



Experiments on Nitrification by Warrington. 



Desirous of testing the question more fully, Mr. R. War- 

 rington has made some experiments at the laboratory of 

 Messrs. Lawes and Gilbert, Rothamsted, England. One 

 Ground for the conclusions of Schloessing and Miintz was 

 that antiseptics, which are fatal to such organisms as those 

 supposed to induce nitrification, did actually stop it. War- 

 rington put portions of rich, moistened garden soil into glass 

 tubes, and forced through them air freed from ammonia. In 

 the first case the air passed through pure; in the second it 

 was freighted with vapor of carbolic acid ; in the third, with 

 carbon disulphide; and in the fourth, with chloroform. In 

 the soil through which the pure air passed considerable nitric 

 acid was formed ; in the others much less the antiseptics 

 hindered nitrification. These results confirmed those of 

 SchloessinGf and Miintz. 



The next question was whether, and under what condi- 

 tions, nitrification could be induced by substances supposed 

 to contain nitrifying organisms. Very dilute solutions of 

 ammonium chloride were put in bottles and allowed to stand 

 some time, and showed no sio-ns of nitrification. Two were 

 then "seeded" with extract from a soil taken from a "fairy 

 ring" that is, abounding in fungoid growth which was sup- 

 posed to include the organisms to whose agency nitrification 

 w r as attributed. One "seeded" and one "unseeded" bottle 

 were placed in the light; another similar pair were kept in 

 the dark. In the seeded bottle in the lisrht no change took 



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