New York Agricultural Experiment Station. 363 



of the acid preparation which they had isolated was in close agree- 

 ment with the calculated composition of the above acid. 



We suggested in our earlier report 3 that the acid analyzed by the 

 above authors must have been contaminated with inorganic phos- 

 phoric acid because wheat bran contains appreciable quantities of 

 inorganic phosphate and by their method of isolation both the 

 organic and the inorganic phosphates would be precipitated at the 

 same time. 



The substances which we prepared from wheat bran and analyzed 4 

 were free from inorganic phosphate, i. e., they gave no precipitate 

 with ammonium molybdate solution. In order to obtain prepara- 

 tions free from inorganic phosphate we found it necessary to precipi- 

 tate the substance repeatedly from very dilute hydrochloric acid 

 with about an equal volume of alcohol. By this process inorganic 

 phosphates are removed because they are more soluble in the 

 dilute acid-alcohol mixture than are the salts of the organic 

 phosphoric acid. 



In this way we obtained a crude preparation of the organic phos- 

 phorus compound which was readily soluble in cold water. Com- 

 bined with it were various bases, calcium, magnesium, potassium, 

 sodium, etc., and also some substance which contained nitrogen. 

 By treating this crude substance in aqueous solution with barium 

 hydroxide the above mentioned bases as well as the nitrogen- 

 containing compound were eliminated. The resulting insoluble 

 barium salts were amorphous and could not be obtained in crystalline 

 form. These salts did not have the composition of barium phytates 

 but agreed approximately with the formulas C25H 5 5054P9Ba 5 and 

 C2oH 4 5049P9Ba 5 ; from both salts an acid was obtained which approxi- 

 mately agreed with the formula C20H55O49P9. All the various prep- 

 arations which were prepared in various ways agreed with the above 

 formulas but since the substances were all amorphous we stated 

 particularly 5 that, " The empirical formulas suggested in this paper 

 are of course purely tentative." 



Although we begged to reserve the further study of this organic 

 phosphoric acid compound as well as the nitrogen-containing sub- 

 stance, Rather 6 in a recent paper reports some work on the same 

 subject. This author had isolated some crude acid preparations 

 from cottonseed meal and wheat bran from which silver salts were 

 prepared. It is claimed that these silver precipitates are pure 

 homogeneous compounds and that they are salts of an organic 

 phosphoric acid of the formula C12H41O42P9. Since these results 

 did not agree with those of any previous investigator in this field, 



3 Loc. cit. 

 4 Loc. cit. 

 6 Loc. cit. 



«Journ. Amer. Chem. Soc. 35:890 (1913); and Texas Agric. Exp. Sta. Bull. 156. 

 (1913). 



