VIII, B, 5 Gibson: Salt Mixtures and Beriberi 353 



polishings had been added, they showed that a definite relation- 

 ship actually existed. The total phosphoric acid content may be 

 used as an indicator of the extent to which rice has been milled 

 or polished, and therefore of its beriberi-producing qualities. 

 These investigators further showed that the protective principle 

 in the rice polishings was soluble in alcohol or in 0.3 per cent 

 hydrochloric acid. Phytin, which comprises 32.5 per cent of the 

 substances soluble in these reagents, was without protective 

 properties. 



Aron and Aron and Hocson ^^ found that nitrogen equilibrium 

 could be maintained on a diet consisting chiefly of white rice in 

 metabolism experiments lasting over a few days. The phos- 

 phorus balance became positive in beriberi cases or in the normal 

 metabolism experiments when rough rice, rice polishings, or 

 phytin were added to the dietary. They also examined the phos- 

 phorus content of 28 samples of rice, for the most part native, 

 and found that the phosphorus content within narrow limits is 

 determined by the grade of milling. Teruuchi,^" however, has 

 recently concluded that the phosphoric acid metabolism is not 

 altered in beriberi. 



From a consideration of the diet on which beriberi developed 

 among the Philippine Scouts, Kilbourne '^ suggests that the 

 disease may be due either to deficient phosphates or to a dispro- 

 portion of calcium and magnesium. Chamberlain, Bloombergh, 

 and Kilbourne ^* concluded that the food supplied was deficient in 

 potassium and phosphorus. Furthermore, analyses of white and 

 unpolished rice showed that the latter contained about twice as 

 much phosphoric acid and two and one-half times the potassium 

 as did the former. In experiments with fowls, the addition of 

 potassium chloride, of phosphoric acid, or of both was without 

 effect. Starvation experiments induced neuritis as evidenced 

 chiefly by histological examination. 



Chamberlain and Vedder '" fed each of 4 groups of fowls on 

 white rice, plus 0.07 gram of potassium diphosphate, potassium 

 citrate, potassium carbonate, and magnesium phosphate, respec- 

 tively. This amount was used because it is slightly in excess of 

 the amount of each of these salts present in 5 grams of rice 

 polishings, which are protective. The fowls developed neuritis. 

 These authors also found that the residue of the alcoholic extract 



" This Journal, Sec. B (1910), 5, 81; ibid. (1910), 98; ibid. (1911), 6, 361. 

 '' Verhandlungen der Japanischen Pathologischen Gesellschaft (1912), 32. 

 " This Journal, Sec. B (1910), 5, 127. 

 ''Ibid. (1911), 6, 177. 

 '"Ibid. (1911), 251. 



