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VII. Investigations relative to the Phosphoric acid 

 (P2O5) Amount. 

 Not only the question in how far the P 2 5 content of 

 the rice-kernels may vacillate, so that the generally accepted 

 minimum of 0,4% P 2 5 would be of doubtful value as a 

 criterium for protection against beri-beri, but also to gain a 

 correct idea of the materials used for various experiments, 

 it was a matter of course that a considerable number of 

 P 2 5 estimations were necessary. 



The conclusions to which these P 2 5 estimations have led, 

 may be in the main formulated in 4 theses: 

 1 st . The P 2 5 amount is not a correct standard for judging 



the prophylactic working of the rice; 

 2 nd . During storing of the rice the P 2 5 content does not 



diminish ; 

 3 rd . The influence of the washing of the rice, both on the 



decrease of the P 2 5 amount and on the diminution 



of the desired working, are generally undervalued, and 

 4 th . Scarcely any of the P 2 5 passes into the water used 



for steaming. 

 Although the values found for the P 2 5 amount should 

 always, for the sake of a more correct comparison, be 

 reduced to those of perfectly dried material, still the 

 ciphers found for undried material are always given here 

 below, because these are of somewhat greater value for 

 practical use. Most investigators seem also to prefer the 

 latter method, and in this way the already mentioned 

 standard of 0,4°/ for P 2 5 amount has also been fixed not 

 with regard to moisturefree but on undried material. All the 

 less can this manner of recording be objected to, because 

 the percentage of moisture in rice, which certainly may 

 vary from 11 to 16°/ very seldom differs appreciably from 

 13 or 14°/ . 



Another observation, of a general kind, as to the P 2 5 

 values should precede the further explanation of the above 

 formulated conclusions, namely that we mention below only 



