Feb. IS, 191S Organic Phosphoric Acid of Rice 427 



over calcium chloric! without vacuum. The moisture was then determined 

 in the salt at 120° to 130° C. and amounted to 0.76 per cent. The 

 phytin from the bran was purified and obtained in the same way as 

 that from unpolished rice, but the barium salt was dried in vacuum over 

 calcium chlorid at 105° C. The moisture determined in vacuum at 105° 

 and at 120° C. was 1.33 per cent in both cases. The crystals resembled 

 those of the first preparation. 



The salts thus obtained were practically free from chlorids and inor- 

 ganic phosphates. Nitrogen was also absent. All the material of the 

 first preparation was used in making repeated determinations of barium, 

 phosphorus, carbon, and hydrogen, but the phytin obtained from the 

 bran was analyzed also for ash constituents other than barium. In 0.60 

 gm. of this material an unweighable trace of calcium was found, but no 

 iron, manganese, magnesium, or potash. The residue on precipitating 

 out the barium and igniting the phytic acid thus left amounted to a few 

 milligrams and was composed mostly of unvolatilized phosphoric acid. 

 No nitrogen was found in the salt. 



The barium in the salts was determined by various methods. A pre- 

 cipitate of barium sulphate was obtained in the determination of phos- 

 phorus by the Neumann method. After boiling the salts for three to 

 four hours with sulphuric acid to which ammonium nitrate was added at 

 intervals, 200 c. c. of water were added to the solution, and the precipitate 

 of barium sulphate resulting from this dilution was boiled and allowed 

 to stand overnight on the water bath. The precipitate was collected on 

 a filter and was washed well, dried, and ignited. This precipitate was not 

 pure barium sulphate, but contained a large amount of silica, aluminum, 

 etc., dissolved from the Kjeldahl flask by the concentrated solution of 

 very hot ammonium nitrate in sulphuric acid. On heating the weighed 

 precipitate with hydrofluoric and sulphuric acids, silica was eliminated 

 and the weight of the residue considerably reduced. In one case 0.6853 

 gm. of precipitate lost o.oi 1 1 gm. by this treatment. A pure barium 

 sulphate was also obtained by fusing the residue with sodium carbonate. 

 The fusion was digested in boiling water, then filtered and washed. The 

 filtrate was tested for barium and the insoluble residue dissolved in a few 

 drops of dilute hydrochloric acid, washed through the filter paper, and 

 the barium precipitated in boiling solution by the slow addition of 0.4 N 

 sulphuric acid. 



A number of determinations were thus made in which the correction by 

 fusion caused a decrease in calculated barium from i to 2 per cent. The 

 results from three samples given in Table I are taken from the analysis of 

 the phytin from bran (not calculated to moisture-free basis). 



Tablij I. — Percentage of barium in barium phylatc oxidized by the Neumann tnelhod 



