proper diet, they usually prevent the development of symptoms 
of the disease. In some instances, however, even when these subs¬ 
tances are constkuents of the diet, when the diet is without va¬ 
riation and composed of very few articles and the individual suf- 
fers from loss of appetite and the assimilative functions appear 
to be poor, and he loses markedly in weight, symptoms of béri¬ 
béri may develop. However, such symptoms may be dispersed by 
causing a variation in the diet by the addition of other nutritions 
substances to it. 
Wheter the degenerations of the peripherial nerves in beri-beri 
resuit directly from trie lack of these nutritious substances, or 
whether these substances are to be regarded as activators or as 
catalyzers, producing the synthesis of certain other nutritive bo- 
dies, or whether they represent anti-bodies which neutralize the 
injurious influence upon the nervous tissues of other metabolic 
substances is not clear. But the préventive substance or substan¬ 
ces against beri-beri in whatever way they act are evidentlv pré¬ 
sent in such very small amounts in the alcoholic ex-trat of rice 
polishings as to suggest that they are not identical with the nu¬ 
tritive substances, and that the nutritive substances are not inges- 
ted as such in this extract, and further that if the lésions of beri- 
beri are aetually forrned as the resuit of the lack of some nutrient 
substance, this substance apparently either must be forrned syn- 
thetically within the body, or be présent as such in other articles 
of the diet ingested by the individuals undergoing our experi- 
ments. 
That the disease produced from these experiments was beri- 
beri, was thoroughly confirmed by the pathological examination 
of the fatal case. The incubation period of the disease is pro- 
bably not less than sixty days, but it varies according to the cha- 
racter of the diet and may be prolonged to even twice this period 
of time. 
Fraser and Stanton found that none of the rices conneeted 
without breaks of beri-beri yielded more than 0,26 % of phospho- 
rous pentoxide. Our experiments show that beri-beri in man may 
be readily produced by a rice containing 0,37 % phosphorous pen¬ 
toxide, when it forms the stable article of a little varied diet. 
For the complété report of these experiments see Philippine 
Journal of Science vol. VII, N° 4, 1912 (now in press). 
(Biological laboratory, Bureau of Science, Manila.) 
