302 DIKTK'riC DiavfCIKNCV. 



found that on heating to 120 degrees Centigrade the curative or 

 preventative principle was destroyed, and he estabhshed its pre- 

 sence in other food-stuffs, notablv beans. 



Breaudat in 1901 used rice pohshings therapeutically in the 

 treatment of human beril)eri. with considerable success. 



Supported by the work of Frazer and Stanton, Schaumann in 

 1908 put forward the theory that deticiency in organically-com- 

 bined phosphorus was the catise of l)eri-])eri. 



In 19JO he found that yeast was ])articularly rich in tlie 

 curative substance, and in n^u Thompson and Simi)Son reported 

 successftil utilisation of yeast in beriberi therapy. Eykman and 

 Funk about the same time showed that the active principle could 

 to some extent be extracted from Ncast by 88 per cent, alcoliol, 

 although Funk points out that the extraction is very imperfect. 



Teruuchi in 1910 obtained an alcohol-soluble procluct from 

 rice polishings which contained comparatively little phophorus, 

 thus militating against the phosphorus deficiency theory of 

 Schaumann. 



As to the state of knowledge in 1911. Funk summarises the 

 position by saying that little was known beyond the fact that the 

 curative substance was soluble in water and in alcohol, was 

 dialysable, and could be destroyed by heating to 130 degrees Cen- 

 tigrade. From this time onward a steady stream of papers appear 

 in various English and ( jerman journals under Funk's name, 

 bearing u])on the chemical and physiological behaviotir of curative 

 extracts i)repared from various sotirces. He finally dis])osed of 

 the phosphorotis deficienc\- theory by isolating, from rice polish- 

 ings, a curative fraction entirely free from phos|)horus. 



By extracting with acid alcohol, lixiviating the evaporated 

 extract with water, preci])itating with ])hospho-tungstic acid, de- 

 composing the ])hosphotungstate with baryta and removing the 

 barium, he finally obtained a highly curative fraction in crystalline 

 form. The yield was extremely small — about half a gram per 

 cwt. of rice polishings. A few milligrams stifinced to cure ])oly- 

 neuritic ])igeons in a few hours. 



Since then he has described a series of fractionings from 

 rice polishings, including cholin, betaine, nicotinic acid, and a 

 crystalline vitamine to which he assigns the empirical formula 

 C2(iH2„N40,j. From yeast he has isolated a vitamine to which he 

 assigns the fornnda C24H19O9N-. 



Other investigators have also isolated comparatively pure 

 crystalline fractions from rice polishings, but in a less definite 

 form. 



According to Funk, the vitamines isolated 1)y him are closely 

 related to the purins and pyrimidins. 



The difficulty in determining their constitution lies in the 

 difficulty of obtaining quantities sufficient for investigation. 



Other Deficieiu'v Diseases. — Considerations of space do not 

 ])ermit of an ecjually detailed resume of other diseases for which 

 vitamine deficiency has been held responsible. 



