414 EXPEEIMENT STATION RECORD. [Vol.36 



ciable interference by vanadium observed. The titrametric method for phos- 

 phorus was also unaffected by the presence of vanadium in amounts far in 

 excess of those usually found in soils. 



See also a previous note by Robinson (E. S. R., 34, p. 806). 



Examination of a radio-active fertilizer, W. P. Joeissen {Chem. Weekbl., 

 13 (1916), No. 39, pp. 1055-1059, figs. 2). — The author reports the examination 

 of a fertilizer which showed a radium content of 0.14X10'*° gni. per gram 

 of dry material. 



The apparatus and manipulation of the emanation method for determining 

 radio-activity are described in detail. 



The solubility of leucite in sulphurous acid, J. Schroeder (Jour. Indus, and 

 Engin. Chem., 8 (1916), No. 9, pp. 779, 780).— Solubility tests of leucite of vary- 

 ing degrees of fineness in sulphurous acid indicate that the potash may be 

 readily dissolved from the leucite rocks by this acid. The materials used 

 varied in fineness from 0.5 to less than 0.1 mm., and the potash dissolved on 

 the basis of K2O present in the samples varied from 41.7 to 76.4 per cent. 



The possibility of the industrial application of this procedure for the extrac- 

 tion of potash by using the smelter gases in the western part of tlie United 

 States near regions where the leucite occurs naturally is indicated. 



Report of the seventh convention of Dutch, food chemists (Chem. Wcekhl., 

 13 (1916), No. 36, pp. 974-1009, fig. 1; Pharm. Weelcbl., 53 (1916), No. 36, pp. 

 1193-1230, fig. 1). — This report contains a short address by the chairman, a 

 short report on the hydrogenation of oils, and analytical notes and data on 

 methods of food analysis as recommended by the Dutch Chemical Society. 



Improved apparatus for use in making acidity determinations of corn, 

 H. J. Besley and G. H. Baston (U. 8. Dept. Agr., Office Sec. Circ. 68 (1016), 

 pp. If, fig. i).— A modified procedure of the method by the authors, previously 

 noted (B. S. R., 31, p. 525), is described. The procedure consists essentially 

 of extraction with 80 per cent alcohol for 30 minutes with the use of an electric 

 mixer, dilution of 25 cc. of the filtrate with 75 cc. of water, and titration with 

 1/100-normal alkali. 



It is indicated that, while there is some variation in the results of acidity 

 determinations by different methods, the electric mixer will extract from the 

 corn in 30 minutes an amount of acid which, for all practical purposes, is 

 comparable to the amount extracted in 80 per cent alcohol after 18 hours diges- 

 tion. 



An improved method for the detection of arachidic acid, R. H. Kerr (.Jour. 

 Indus, and EvgUi. Chem., 8 (1916), No. 10, p. 904). — A method for which the 

 advantages of greater convenience, a lessening of the number of operations, a 

 reduction of the amount of attention required, and the avoidance of the use of 

 ether are claimed over the Renard method as adopted by the Association of 

 Official Agricultural Chemists (E. S. R., 20, p. 512) is described. 



The procedure consists of saponifying the oil with alcoholic potash and 

 neutralizing excess alkali with acetic acid after saponification is complete, 

 l^'ifty cc. of 5 per cent magnesium acetate is then added, and the mixture heated 

 to boiling, cooled, and placed in a refrigerator at a temperature of from 10 to 

 15° C. until the next day. The solution is filtered, the precipitate washeti 

 twice with 50 per cent alcohol and three times with distilled water, and returned 

 to the original flask. One hundred cc. of hot distilled water is then poured into 

 the flask and sufficient dilute sulphuric acid added to decompose the magnesium 

 salts. The flask and contents are heated until the acids form a clear layer, the 

 flask is cooled, the acid solution decanted, and 100 cc. of hot water added to 

 wash the fatty acids. After cooling, the solidified cake of acids is freed as far 



