— 178 — 



standing they had a sufficient P 2 5 content, were totally 

 unfit for giving protection against beri-beri, as shown by 

 the described effect on test-animals. If this is already the 

 case with raw rice, how much more so after it has been 

 washed and steamed! 



The remark might here be made that the standard limit 

 of 0.4% for Po0 5 amount is only valid when the method 

 followed for fixing it, is that in which the rice alone is 

 reduced to ash; that therefore, when combustion takes place 

 with KXO3 and Na 2 C0 3 , this limit must be higher and 

 would, according to the above given explanation, have to 

 be fixed at 0,42 — 0,44%. Be that as it may, the beha- 

 viour of the birds fed on Loemadjang rice was so unsatis- 

 factory, that an increase of the quantity of silver-skin to a 

 proportion of only a few hundretli percent of P 2 5 may 

 not be considered as able to sufficiently counteract these 

 phenomena. 



The other distinct, although somewhat less speaking proof, 

 that the accepted cipher 0,4 as value-limit for the P 2 5 

 content is not really to be relied upon, was given by means 

 of an investigation of a sample of rice which, according 

 to Dr. G. W. Kiewiet de Jonge, had been the cause of a 

 striking increase of beri-beri cases in kampong Kramat. 

 In this case too, the rice could not be rejected on account 

 of its P 2 5 amount for this proved to be 0,42% (calculated 

 from dried material 0,48%). The experiments with spirit, 

 when there was a dry-residue of only 0,37%, gave on the 

 contrary sufficient reason for rejection. The incapacity of 

 this rice to prevent beri-beri was further confirmed by 

 experiments with three polyneuritic rice-birds, of which two 

 recovered only slowly in 3 or 4 days, and the third got so 

 much worse after one day that it appeared desirable to 

 relieve it from further experimentation. 



If it was proved by these two cases that it is not unusual 

 to find kinds of rice, the kernel of which contains such a 

 comparatively high P 2 5 amount that this may be increased 



