ETIOLOGY OF BERIBERI. 411 



the outbreaks yielded not less than 0.4 per cent of that sub- 

 stance." More recently Reiser '■'* advocates lor the prevention 

 of beriberi the passage of a lav^^ placing a tax upon rice which 

 contains less than 0.4 per cent of phosphorus pentoxide, such rice 

 being regarded legally as polished rice, and no tax on rice which 

 contains 0.4 per cent or more of phosphorus pentoxide, such 

 rice being regarded legally as an unpolished rice. Although 

 it seems quite definite that a rice containing this amount of 

 phosphorus will prevent the appearance of polyneuritis in fowls, 

 nevertheless, from our experiments it is evident that beriberi in 

 man may be produced by rice containing 0.37 per cent of phos- 

 phorus pentoxide when it forms the staple article of a little 

 varied diet. Therefore the question arises as to whether the 

 margin of safety is sufficient between such a rice and that con- 

 taining only 0.4 per cent of this substance. Since it has been 

 generally admitted that the higher the phosphorus content of 

 rice the less is the liability of that rice to produce beriberi and 

 since Fraser and Stanton found as an average result of all their 

 examinations that unpolished rice contained 0.54 per cent of 

 phosphorus pentoxide and Aron '"' found that unpolished rice 

 in the Philippine Islands contains 0.557 per cent of phosphorus 

 pentoxide and freshly husked rice 0.455 per cent, before legis- 

 lation is enacted it would seem to be advisable to consider 

 carefully the question of the amount of phosphorus pentoxide 

 which a rice should legally be required to contain in order for 

 it to be regarded as an unpolished rice and to be exempt from 

 taxation in the Philippine Islands. 



**Jouni. Trop. Med. & Hyg. (1912), 15, 124. 

 ^This Journal, Sec. B (1910), 5, 81, 98. 



