New York Agricultural Experiment Station. 171 



A portion of the above crystalline barium salt was used for the 

 preparation of the free acid. The substance was, however, not 

 pure and it had not been washed free of the mother liquor. The 

 acid was prepared by the usual method, that is, the barium salt was 

 decomposed with a shght excess of sulphuric acid, the filtered solution 

 precipitated with copper acetate, the latter filtered, washed and 

 decomposed with hydrogen sulphide, again filtered and the filtrate 

 evaporated in vacuum at a temperature of 40-45° and finally dried 

 in vacuum over sulphuric acid. In appearance and reactions the 

 acid was practically identical with phytic acid except that after 

 boiling with dilute hydrochloric acid and neutralizing it slightly 

 reduced Fehhng's solution. This reduction, however, we believe 

 to be due to admixed impurities; for, as stated above, the acid was 

 not prepared from a pure compound. 



The aqueous solution of the acid coagulates egg albumen at once. 

 As has been already mentioned phytic acid gives the same reaction 

 as well as the inosite esters of phosphoric and pyrophosphoric acids. 

 Apparently, therefore, no special significance can be attached to 

 this reaction. 



The acid gave the following result on analysis after previously 

 drjdng at 105° in vacuum over phosphorus pentoxide: 



Found C = 11.71; H = 3.07; P = 26.35 per ct. 



The crystalline precipitate mentioned on page 6, which separated 

 from the solution of the first barium precipitate in 0.5 per ct. 

 hydrochloric acid, was treated with about 5 per ct. hydrochloric 

 acid in which the greater portion dissolved. The insoluble matter 

 was removed by centrifuging and the solution precipitated with 

 alcohol. This operation was repeated a second time when the 

 substance was obtained nearly white. It differed from the first 

 preparation in that its solution in dilute hydrochloric acid was 

 neither mucilaginous nor opalescent. For further purification the 

 substance was first precipitated by barium hydroxide from its dilute 

 hydrochloric acid solution, and then twice precipitated from dilute 

 hydrochloric acid with alcohol. The precipitates produced by the 

 alcohol were amorphous at first but when allowed to stand over 

 night in the mother liquor they always changed to the same crystal- 

 line form as previously mentioned. 



After precipitating the last time with alcohol the substance was 

 quickly filtered, washed in dilute alcohol, alcohol 3.nd ether and 

 dried in vacuum over sulphuric acid. The product was a snow- 

 white amorphous powder and it weighed 7.4 grams. 



The filtrate from the above was allowed to stand over night when 

 a small amount of the substance crystallized out. The crystals 

 were filtered, washed in dilute alcohol, alcohol and ether and dried 

 in the air. The substance was free from chlorine and gave no 

 appreciable color reaction with phloroglucine or orcine. For analysis 

 it was dried at 105° in vacuum over phosphorus pentoxide. 



