418 EXPERIMENT STATION RHCORl). 



of ii funnel in ;i sand halli. Kx aporate to drynt'ss and heat ina muffle at a low 

 red lieat until oxalic acid is completely removed. Pulverize the residue and 

 wash with hot water into a 250 cc. flask. Allow the solution to stand over 

 night, shaking from time to time. Make the volume to 250 cc. ]i!ns 10 cc. for 

 volume of soil. Filter and evaporate 200 cc. of the solution, corresponding to 

 20 gm. of soil, and again treat the residue with oxalic acid. Filter and deter- 

 mine potash by adding hydrochloric acid and platinum chlorid or nitric acid 

 and perchloric acid in the usual way. If it is desired to determine potash by 

 weighing the reduced platinum, the method may be simplified by evaporating 

 t he 200 cc. directly with hydrochloric acid and platinum chlorid. 



On a volumetric method for the determination of phosphoric acid in super- 

 phosphates. S. KoHN (CJicm. Zig., 32 {1908), lYo. 39, pp. //7'.5, J,76; obs. in ('hem. 

 Zenthl., J908, I, No. 26, p. 2205; Analyst, 33 {J90S), No. 390, p. 376; Vlinn. 

 Abs., 2 {1908), No. 18, p. 2529). — The essential features of the method are titra- 

 tion of the water extract (20 gm. of superphosphate to 350 cc. of water) with 

 sodium hydroxid solution, using methyl orange as indicator ; addition of a large 

 excess of neutral calcium chlorid solution ; and further titration with the soda 

 solution, using phenolphtha'lein as indicator. The results obtained agree well 

 with those obtained with the citrate method. 



The volumetric determination of water-soluble phosphoric acid in super- 

 phosphates, W. MoELLER {Clicin. Ztg., 32 {1908), No. 53, pp. 631, 632; ub>i. in 

 Chcm. Zenlbh, 1908. II, No. 5, p. -'i-'i'i ; Chem. Abs., 2 {1908), No. 18, p. 2529).— 

 The author questions the accuracy of the Kohn method described above. 



On the titration of phosphoric acid in superphosphate solutions, S. Kohn 

 and L. Schucht {Chem. Ztg., 32 ( 1908), No. 61, pp. 718, 719; abs. in Chem. Abs., 

 2 {1908),' No. 20, p. 2767). — In this article Kohn briefly discusses the contribu- 

 tions of Schucht and Liftman to this subject and replies to criticisms of his 

 method referred to above. The weaknesses of Kohn's method are commented 

 upon by Schucht. 



The systematic investigation of drinking waters, G. Romijn {Pharm. 

 Weelxbh, Jj5 {1908), No. 15, pp. J,02-Jil2, fig. i).— The apparatus and procedure 

 adapted to the systematic determination of chlorin, sulphuric acid, carbon 

 dioxid, alkaline earths, nitrates, permanganate consumption, calcium and mag- 

 nesium ions, and alkali ions are described. 



Determination of combined carbonic acid in water, G. Lunge {Ztschr. 

 Angcw. Chem., 21 {1908), No. 18, p. 833; abs. in Chem. Abs., 2 {1908), No. U,, 

 p. 19-'i2). — The error of 33 per cent in temporary hardness reported by Noll in 

 his tests of Lunge's method is attributed to the presence of a large amount of 

 iron in the water. The author maintains that in ordinary waters containing 

 small amounts of iron there is no appreciable error in the determination of 

 temporary hardness. 



The determination of combined carbon dioxid in water, H. Noll {Ztschr. 

 Angeiv. Chem., 21 {1908), No. 27, pp. lJf55, 11,56).— A reply to the above state- 

 ment of Lunge, maintaining that even with waters containing comparatively 

 small amounts of iron the results by Lunge's method are too high. 



Examination of eggs with colored shells, K. Rorchmann {Ztschr. Fleisch ii. 

 Milehhyg., 18 {1908), No. 6, pp. 1 82-18 '{).— The data reported have to do with 

 the examination of wild birds' eggs marketed for food purposes. According to 

 the author, water gave better results than salt solution in judging eggs by 

 their specific gravity. 



The formic acid content of honey, K. Farnsteiner {Ztschr. Untersvch. 

 Nahr. u. Genussmtl., 15 {1908), No. 10, pp. 598-60.',). —The studies reported of 

 the acid content of honey led to the conclusion that if formic acid is pi*eseut it 

 exists only in minute quantities, and the author recommends that for the 



