536 EXPERIMENT STATION RECORD. 



The electrical production of nitric acid from the elements of the air, 

 L. Granueau (Ann. .S'c/. Af/ron., 3. sci:, 1 {1006), xYo. 1, pp. 1-60, fjjjs. 29).— The 

 works, apparatus, and methods employed at Notodden, Norway, are quite fully 

 described. This article is also published as a separate. 



Oxidation of nitrogen by silent discharges in atmospheric air, E. Warburg 

 and G. Leithauser (Ann. Plujs., J,, ser., 26 {W06), Xo. -'/, pp. I'tS-'tSO; ahs. in 

 Amer. Jour. .S'c/., //. scr., 22 (1906), No. 131, p. 462).— The authors report a series 

 of experiments from which they conclude that" (1) nitrose gases in the presence 

 of ozone are easily absorbed by dilute soda lye; (2) with silent brush dis 

 charges from the positive terminal sphere in atmospheric air, at the room tem- 

 perature, independently of the moisture of the air, 10 liters of NO is oxidized 

 by an ampere hour; (3) the oxidized quantity of nitrogen mixture increases 

 with increasing temperature and then decreases with the formation of the 

 ozone; (4) a quantity of N2O4, indicating 1 cc. NO in 1,500 cc. lessens the forma- 

 tion of ozone when the silent discharge occurs in atmospheric air." 



Nitric acid and other spark reactions {Jahrh. Elektrochem., 11 (1904), pp. 

 610-615). — The literature especially of investigations relating to the prepara- 

 tion of nitric acid from the atmosphere is reviewed. 



A domestic supply of nitrogen, N. Card (Ztschr. Angew. Chein., 19 {1906), 

 No. 37, pp. l.'>69-1581, figs.'o). — Statistics of production and consumption of 

 nitrogen compounds are given, and the apparatus and processes used and the 

 commercial success attained in the manufacture of nitrogen compounds, espe- 

 cially calcium cyanamid, potassium cyanid, and nitrates, are described. It is 

 stated that the cost of production in these methods is still too high to enable 

 the products to couqiete successfully with the natural supplies except possibly 

 in special cases of unusually cheap power, etc. 



Nitrogen lime, its use and action (Dent. Lnndw. Pres.^e, 33 (1906), No. 48, 

 pp. J,05, J,06; LaiKlw. Wchiihl. Schles.-Holst., 56 (1906), No. J,0, pp. 602, 603).— 

 A brochure on this subject by Miinzinger of the Darmstadt experiment station 

 is briefly reviewed. 



Apparatus for the preparation of lime nitrogen and ammonium sulphate 

 according to the methods of the Cyanid Company of Berlin (Dciit. Landw. 

 Presse, 33 (1906). No.s. 76, p. 606, figs. 4; ''O, p. 631, fig. i).— The construc- 

 tion and operation of the furnaces and other apparatus used in preparing 

 these compounds by the Frank and Caro and Siemens processes are described 

 and illustrated. 



The making of sulphate of ammonia (Amer. Pert., 25 (1906), No. 4, pp. 

 5-tO, figs. 3). — This article discusses briefly the value of ammonia in agricul- 

 ture and describes the methods used in preparing anunonium sulphate by the 

 destructive distillation of coal. 



Treatment of vinasse and molasses for recovery of nitrogenous matter 

 after removal of potash, Vasseux (BiiI. Assoc. Chiiii. Hiicr. ct Distill. 23 

 (1906), No. 12, pp. 1381, 1382; abs. in Jour. Soc. Chein. Indus., 25 (1906), 

 No. 16, p. 823). — The author points out that while the nitrogenous matter con- 

 tained in molasses is more valuable than the potassium salts present, the 

 former is generally lost by incineration during the process of working up the 

 saline matter. He proposes the following method for its recovery : The 

 vinasse is concentrated and treated with sulphuric acid, thus converting the 

 potash into sulphate, which crystallizes out. The mother liquors are then evapo- 

 rated to dryness in an apparatus of special construction, yielding a residue 

 containing from .T to 7 per cent of nitrogen and to 7 per cent of potash. 



On the practical value of lime nitrogen as a fertilizer, W. voN Knierim 



