Casimir Funk 7 



ganic solvents, was systematically investigated in conjunction with 

 J. C. Drummond. After the Separation of impurities it was planned 

 to transform the vitamine by benzoylation, acetylation or similar 

 reaction into a stable Compound. The experimental data follow. 



Experimental. i. Extraction and precipitation. Three 

 k. of ordinary brewer's yeast were extracted with alcohol, and 116 

 gm. of the evaporated extract treated in the cold with 500 cc. of 10 

 percent sulfuric acid sol. for two days, with f requent shaking. The 

 acid extract was filtered through a folded filter, the residue washed 

 with 500 cc. of water, and the filtrate precipitated with 50 percent 

 phosphotungstic acid sol. After standing over night, the precipi- 

 tate was removed with suction. 



Phosphotungstate precipitate. The precipitate obtained by 

 the f oregoing process was ground up with acetone in a mortar. The 

 small residue that remained was obtained, by suction, on a filter and 

 washed repeatedly with acetone. This acetone-insoluble residue, 

 amounting to 19.8 gm., was emulsified, in a mortar, with a little 

 water and mixed well with 60 gm. of neutral lead acetate. The 

 whole mixture was then shaken on a machine. The resultant lead 

 phosphotungstate was separated by filtration and the filtrate freed 

 from excess of lead with hydrogen sulfid. The acetone-soluble part 

 was diluted with water and shaken with an excess of lead acetate. 

 The lead phosphotungstate was separated by filtration and the ex- 

 cess of lead in the filtrate removed with hydrogen sulfid. All the 

 lead saks obtained during the process were decomposed with hy- 

 drogen sulfid ; the phosphotungstic acid was removed quantitatively 

 by means of baryta. 



Results of animal experiments. The Solutions of all the frac- 

 tions were diluted to known volumes and aliquot parts used for 

 tests on beriberi pigeons. With the ac&tonc-insohtble fraction 

 three pigeons were cured by i/50th of the total volume. Pigeons 

 given polished-rice, and a dose of the Solution every few days, main- 

 tained their health and weight as described elsewhere (8). 



The acetone-soluble fraction was tested on two pigeons and 

 found to be entirely inactive, although the dose was three times 

 as large as that for the acetone-insoluble fraction. The action of 

 each of the decomposed lead salts was tested on two pigeons with 



