THE ETIOLOGY OF BERIBERI. 59 



It will be understood that these three experiments were in progress 

 simultaneously and that the fowls were in all respects under identical 

 conditions. 



Experiment D. — Part of the original paddy was taken and milled by a Malay 

 woman by primitive methods into the finished product as eaten by Malays. 

 Eight fowls, fed for five weeks on the rice prepared from the original paddy 

 by the Malay method, remained healthy. Eight fowls only were used for this 

 experiment, as the quantity of paddy then remaining sufficed only for this 

 number for the time it was estimated the experiment would last. 



Attention is drawn to the important point that the products used in 

 these experiments were all derived from the same lot of paddy, and the 

 results force us to the conclusion that it is the polishing process, which 

 is essentially at fault: the polishing of white rice removes from the 

 seed some substance or substances essential for the maintenance of the 

 normal metabolism of nerve tissues. 



To elucidate the point as to whether rice when freshly milled is less 

 harmful than that which has become stale, an assistant was stationed 

 in Singapore who sent daily to the laboratory by the most expeditious 

 route a. quantity of rice milled on the day of dispatch. Twelve fowls 

 were fed on this rice and five developed polyneuritis in four weeks. 

 This result, which is similar to that obtained in other experiments, 

 when fowls were fed on rices milled from four weeks to two years pre- 

 viously, disposes of the suggestion that the harmfulness of white rice 

 is due to its staleness or the development in it of a poisonous substance 

 or substances subsequently to its being milled. The root of the evil 

 lies in the milling process itself. The result further indicates the in- 

 adequacy of preventive measures founded on the poison hypothesis in 

 regard to the use of freshly milled rice. 



An experiment was now planned to determine whether a parboiled 

 rice proved harmless, could by exhaustion with hot alcohol be reduced 

 to such a condition that it would produce polyneuritis when fed to 

 fowls, and whether the substances so extracted when fed to fowls with 

 a white rice proved harmful could prevent the development of poly- 

 neuritis. For this purpose parboiled rice was repeatedly exhausted with 

 hot alcohol. The alcoholic extracts were concentrated in vacuo at a 

 temperature of 52°, freed from alcohol and the residue emulsified in 

 distilled water. Experiments with these- products showed that fowls fed 

 on the exhausted, parboiled rice contracted polyneuritis, and that birds 

 fed on a white rice proved harmful by previous experiment remained 

 healthy if they received in addition a quantity of the extract- 

 Having by" these and other experiments, the details of which are 

 omitted so as not to encumber the argument, arrived at the point where 

 it was clear that the essential cause of beriberi was to be sought for in 

 a nutritive defect, further efforts were made to determine by chemical 



