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those results which were obtained after igniting the finely 

 powdered material, with 0,1 part kalium Ditrate (KN0 3 ) 

 and 0,3 parts natrium carbonate (Na 2 C0 3 ). 



If rice alone is combusted, for the purpose of determining 

 the amount of P 2 5 , then there is more or less loss of 

 organically-combined phosphorus depending upon whether the 

 temperature increases rapidly and to a higher degree, or 

 whether it is reached more gradually and kept at a lower 

 heat. In this manner lower results are obtained than when 

 the ignition takes place after the rice powder has been 

 mixed with KN0 3 and Na 2 C0 3 ; these differences may be 

 of relative importance. As a rule, the difference is 5% 

 when the reduction to ash, without any admixture, takes 

 place slowly and is not carried to a high temperature. There 

 is a difference of 11% when the temperature is rapidly 

 increased and to a high degree, with this understanding 

 that, when the actual P 3 5 amount is l°/ , the P 2 5 obtained 

 from the ash is in the first case 0,95°/ while in the last 

 case generally not more than 0,89% is found. 



Communications as to the results of the P 2 5 estimations 

 are consequently only of actual value, when at the same time 

 it is shown which method of analysis has been followed. 



1 st . The P 2 5 Content of the Bice does not diminish 

 during Storage, 



Several experimentists have declared that the P 2 5 amount 

 becomes less during ordinary storage. One of the latest 

 communications on this point appeared in the treatise of 

 J. A. M. J. Jennissen: On Rice-diet and Beri-beri amongst 

 the Miners in Billiton" which is published in the „Genees- 

 kundig Tijdschrift voor Nederlandsch-Indie" 1913 (Medical 

 Magazine for Netherlands India 1913 Volume 53, part 4, 

 pages 578 and further). This gives investigations made by 

 the mining engineer C. P. Gboothoff, in consequence of 

 which the conclusion is drawn, that garnering for even 

 2'/ 2 months has already a distinct influence on the ash and 

 on the P 2 5 amount. 



