112 EXPERIMENT STATION RECORD, 



Estimation of the lime requireraent of soils, J. A. Bizzell and T. L. Lyon 

 (Jour, r.idus. and E}vgin. Chem., 5 (1913), No. 12, pp. 1011, 1012; ahs. in 

 Science, n. ser., 38 (1913), No. 983, p. 640).— This is a modification of the 

 Albert method (E. S. R., 23, p. 11), as follows: 



" Place 25 gm. of the air-dried soil in a Jena Kjeldahl flask. Cover with 50 cc. 

 boiled distilled water and add 50 cc. tenth-normal barium hydroxid solution. 

 Digest in a briskly boiling water bath for one hour with occasional shaking. 

 Eemove from the water bath, add 150 cc. distilled water and 5 gm. solid am- 

 monium chlorid. Connect the flask with a nitrogen distillation apparatus and 

 distill. Collect the distillate (150 cc.) in tenth-normal acid and titrate, using 

 methyl orange as indicator. The strength of the barium hydroxid is determined 

 by titrating directly 50 cc. of the solution, using methyl orange as indicator. 

 The difference between the two titrations, therefore, represents the amount of 

 barium hydroxid absorbed by the soil. A correction is made for the slight de- 

 composition of ammonium chlorid when heated with soil." 



The estimation of citric acid-soluble phosphoric acid in Thomas slag' 

 powders according to the citrate and Lorenz methods, H. Neubaler {Landw. 

 Vers. Stat., 82 (1913), No. 5-6, pp. 465-415).— The results obtained with the 

 Lorenz method were found to agree with the true phosphoric acid content 

 I)resent in the fertilizer. It was furthermore noted that the presence of citric 

 acid had no effect upon the results obtained by the Lorenz method. 



The results given by the citrate method were always high even though the 

 specifications proposed by Popp (E. S. R., 29, p. 410) were closely followed. 

 The chief reason for the high results is said to be the precipitation of several 

 milligrams of calcium oxid as tricalcium phosphate. As weighable amounts of 

 phosphoric acid do not remain in the filtrate, due to the incomplete precipitation 

 of this acid, compensation for the calcium weighed as phosphoric acid is not 

 possible. The error is deemed greater in Thomas slag powder than that foimd 

 in the estimation of the water-soluble phosphoric acid in superphosphates, inas- 

 much as slag powder contains much more calcium. 



The loss in lecithin phosphoric acid, R. Cohn (Chem. Ztg., 37 (1913), No. 57, 

 pp. 581-583). — Lecithin is usually not entirely extracted by ether, consequently 

 certain investigators, notably among them Hoppe-Seyler, recommend the use of 

 alcohol in the method for the purpose of breaking up the lecithin protein com- 

 plexes. According to theorj' adsorption of the lecithin by the coagulated pro- 

 teins would not take place, but, on the other hand, such goods as egg yolk, baked 

 goods containing eggs, lecithin preparations, etc., show a loss of their lecithin 

 content extractable by ether as time goes on. If only cleavage took place, the 

 amount of lecithin extractable by ether should be higher. 



In order to determine whether this loss is really due to adsorption, fresh egg 

 yolks were treated with dilute copper sulphate solution and 0.71 per cent (90 

 per cent) of the total lecithin was extracted by ether. Without the use of cop- 

 per sulphate only 0.45 per cent of lecithin was obtained. Adsorption was found 

 to take place when lecithin was added to white of egg, but when treated with 

 alcohol and ether almost all of the entire amount added was recovered. Heat- 

 ing 20 hours at 100° C. was found to bring about a retrogression not only of 

 the ether-soluble lecithin but also of the total lecithin phosphoric acid. The 

 difficulty of extracting the total sulphuric acid in vulcanized rubber is stated 

 as an analogous case. The author believes that the diminution of ether-soluble 

 phosphoric acid can be explained by the adsorption theory. 



Becommendations for the revision of the section on honey and honey 

 surrogates (Mitt. Lebemm. Untersuch. u. Hyg., Schweiz. Osndhtsmnt., 4 (1913), 



