476 



A New Source of Nitrates. 



[NOV., 



extraction of nitrogen from the air is that discovered by 

 Professor Birkeland and Mr. Eyde, which results in the pro- 

 duction of nitrate of lime. Both of these processes, however, 

 necessitate the employment of electricity, which can only be 

 produced economically where cheap water power is available. 



Recent investigations by Messrs. Muntz and Laine * on 

 nitrification in peat have suggested a new source of nitrates which 

 may have some importance for purchasers of nitrogeneous 

 manures. Previous investigations had shown that soils rich in 

 organic matter are particularly suitable for the production of 

 nitrates, and this made it probable that peat, the result of the 

 decomposition of vegetable matter in water, and composed 

 almost entirely of carbonaceous material, would afford a favour- 

 able basis for the activity of the nitrifying organisms. Peat in 

 various stages of decomposition has been experimented upon 

 with this object. It has been found that when broken into 

 pieces, mixed with lime, and treated with a weak solution ol 

 sulphate of ammonia, after the addition of the nitrifying 

 organisms, peat has exhibited an extraordinarily active nitri- 

 fication, much surpassing that of any materials previously 

 employed. 



In earlier experiments, the maximum intensity of nitrification 

 had been obtained by a solution of salts of ammonia acting on 

 animal black. By substituting peat for animal black, the 

 production of nitrate was much more rapid. All kinds of 

 peat proved very effective, but the light and spongy kinds, 

 less advanced in decomposition, were found somewhat better, 

 probably because they allowed a more active circulation of the 

 air, while liquids penetrated them more completely, and . the 

 nitrifying organisms were able to act upon the extensive 

 surface presented by the filaments. It was found that the 

 organisms remained on the peat and continued their nitrifying 

 action indefinitely so long as they continued to be fed. The 

 method adopted is to saturate the peat with an ammoniacal 

 solution, with the result that the liquid becomes nitrified. I 

 is allowed to drain through the peat, and the nitrates are 

 obtained by evaporation. 



* Bui/, de la Soc. Nat. cTAgric. de France, No. 6, 1906. 



