SOILS FERTILIZERS. 225 



No. 21, p. 2602). — The injury resulting to beets from top-dressing with nitrate 

 of soda in dry weather is explained on the basis of Miintz and Gaudechon's 

 investigations (E. S. R., 21, pp. 23,621) as due to a localized and concentrated 

 solution of the salt. 



The great guano deposits of Peru (Bui. Internat. Bur. Amcr. Repub. {Eng- 

 lish Sect.), 29 {1909), No. 5, pp. 88-'i-891, figs. 5; Soi. Amer. Sup., 69 {1910), No. 

 1775, pp. 28, 29, figs. 5). — The guano deposits are described and the history and 

 present status of tlie industi'y are briefly discussed. Attention is also called to 

 the proiwsal to protect the guano-producing birds and thus to insure a coutinu- 

 jiiice of the sui)p]y of guano. 



The development of the ammonia industry in gas works during the last 

 fifty years, R. W. Hilgenstock {Chcm. Engin., 10 {1909), No. 3. pp. 77-83, figs. 

 12). — Progress in processes and apparatus, and cost of production by certain 

 German processes are reviewed. 



Brief statistical notes on sulphate of ammonia, Siemssen {Dent. Landw. 

 Prcssc, 36 (JHOH). No. 93, p. 993, <lgiiis. J). — The i)n)duction and consumption of 

 sulphate of ammonia in Germany are presented in notes and diagrams. It is 

 shown that the production increased from 79.000 tons in 189.5 to 291.000 tons 

 in 190S, while the consumption increased from about 50,000 tons in 1895 to over 

 310,000 tons in 1908. The exi)ort increased from an insignificant amount in 

 1895 to about 70,000 tons in 1908. The imports have been very variable, but 

 were only slightly greater in 1908 than in 1895. 



Ammonia from soot, J. E. Steely (Power and Engin., 31 {1909), No. 22, 

 p. 929). — The reactions l)y which ammonium compounds are produced in the 

 combustion of coal are explained and attention is called to the importance of 

 jircveiiting this source of waste. It is estimated that with a plant using 100 

 tons daily of coal containing 1 per cent of nifrogen and 2 per cent of sulphur 

 there would be produced more than 4 tons of ammonium sulphate per day worth 

 over $200. 



On the electrochemical fixation of atmospheric nitrogen, A. Zammarchi 

 {Comment. Ateneo Brescia, 1908, pp. 131-180, pi. 1, figs. 13). — This is a review 

 of the different methods of obtaining nitrogen from the air. A bibliography of 

 61 references is appended. 



Manufacture of lime nitrogen, II, F. Foerstek and H. Jacoby {Ztschr. 

 EU'ldroehem., 15 {1909), No. 21, pp. 820-83.'t. figs. .J).— This is a continuation of 

 :i previous discussion of the subject (E. S. R., 19, p. 423) and deals particularly 

 with the relation of temperature with and without addition of other substances 

 (calcium chlorid and fluorid and potassium chlorid) to the rate of formation of 

 calcium cyanamid. Observations, especially upon the self-heating of the mass 

 accompanying the formation of the cyanamid, are recorded in detail. 



The inJlustry of cyanogen derivatives as related to atmospheric nitrogen, 

 M. Manuelli, trans, by M. Quesneville {Eiigrais, 2'/ {1909), Nos. 32, pp. 

 887-893; 34, pp. 9 4 1-9. ',3). —The hi.story and present status of this industry are 

 quite fully stated and the principles underlying the processes employed are 

 explained. 



The cyanamid industry of France, C. Pluvinage (6/^7. Soc. Encour. Indus. 

 Nnt. [Paris], 111 (1909), No. 3, pp. 549-562, figs. 3; abs. in Nature [London], 

 81 (1909); No. 2077, pp. 222, 223).— This article describes the plant and methods 

 of manufacture used at Notre Dame de Briangon, France, where abundant 

 water power is available. Results of tests of the fertilizing value of the 

 cyanamid are also reviewed. The author concludes as a result of his observa- 

 tions that the material may be used with advantage at rates of from 150 to 250 

 kg. per hectare (133.5 to 222.5 lbs. per acre) applied before planting. It may be 



