SOILS FEKTILIZEES. 125 



found that the oxidation proceeds in a series of stages compatible with the 

 hypothesis that the hydrogen atoms are successively hydroxylated with the 

 subsequent elimination of water. Hydroxylamin salts and salts of hypouitrous 

 and nitrous acids wore found as intermediate compounds. " The loss of nitrogen 

 which invariably takes place to a certain extent on such filters is due, in part, 

 to complex interactions between these various intermediate compounds, and as 

 the relative concentration of these compounds is determined by the degree of 

 aeration of the filter, this hypothesis is in correlation with the observed dif- 

 ference in the loss of nitrogen between a percolating filter and a contact bed." 



Synthesis of the oxids of nitrogen by the electric arc, E. Roselieb {Bui. 

 Assoc. Ingcn. Elect. Liege 13 {1013), pp. 566-646; Rev. Electrochim. et Electro- 

 metal, 8 {lOl-'t), Nos. 2, pp. 33-50; //, pp. 91-111, figs. 11; ahs. in ScL .16s., 

 Sect. B— Elect. Engln-., 17 {19U), No. 6. p. 305).— X rather full discussion of 

 the theoi'y and processes of electrical fixation of the free nitrogen of the air, 

 especially the oxidation of the nitrogen, is given. 



The appliances used and the works in operation are described and the future 

 of the industry is discussed. 



When should lime nitrogen be applied to winter grains? P. Wagnes {Deiit. 

 Landw. Presse, J{2 {1915), No. 6, pp. 39, JfO). — Experiments are reported which 

 Indicate that the best results will be obtained on light well-drained soils by 

 applying the lime nitrogen about the middle of February if the weather con- 

 ditions are favorable. If the weather is very cold, vegetation backward, or the 

 soil still covered with snow it may be advisable to delay the application from 

 8 to 14 days. Sodium nitrate apparently gives the best results when applied 

 not earlier than the first of March. 



Nitrogenous fertilizers from refuse substances, C. Elschnee {Amer. Pert., 

 42 {1915), No. 5, pp. 21-23, fig. 1). — Methods of preparing available nitrogenous 

 fertilizers from such substances as wool, hair, shoddy, rag, felt, and leather 

 waste are briefly described. The methods are, as a rule, based upon treatment 

 with sulphuric acid, sometimes with the addition of other substances, such as 

 nitrate, to hasten the reduction. 



Availability of the nitrogen in Pacific coast kelps, G. R. Stewaet {TJ. S. 

 Dept. Agr., Jour. Agr. Research, 4 {1915), No. 1, pp. 21-38).— The availability 

 of the nitrogen of the kelps was measured by its rate of ammonification and 

 nitrification as determined by the so-called beaker method of soil bacteriology. 

 The tests were made with drietl and ground kelp. 



Ammonification and nitrification of this material in fresh field soil were 

 found to vary with different species and with the manner of preparation. The 

 nitrogen of Nereocystis luetlceana was found to be relatively very available, 

 while that of PelagopJiycus porra ammonified and nitrified less readily. The 

 nitrogen of Macrocystls pyrifera, which is the variety of greatest commercial 

 importance, changed verj' slowly in the soil. It was most available when the 

 kelp was added to the soil in a fresh or only partially dried condition and 

 decreased materially when it was fully dried. Removing the salts by leaching 

 did not increase the rate of decomposition. 



"The addition of moderate quantities of Nereocystis to a sample of fresh 

 soil in the laboratory did not cause any great interference with either ammonifi- 

 cation or nitrification of readily available organic matter, such as dried blood. 

 Similar experiments with Macrocystis showed at first a decrease in the rate 

 of transformation, especially in nitrification. ITiis decrease did not con- 

 tinue and as time passed the ammonification and nitrification became prac- 

 tically normal." 



A bibliography of twenty references to literature bearing on the subject is 

 appended. 



