424 SCIENCE PROGRESS 



In speaking of these observations I wish to acknowledge the 

 priority of Dr. Gowland Hopkins, whose usual modesty had 

 prevented him from putting forward his own important con- 

 tributions to the subject. Ill health delayed Dr. Hopkins from 

 publishing work which showed the deficiency of white flour as 

 a life-sustaining food. I leave it to Dr. Casimir Funk to discuss 

 the chemical nature of these active substances which form so 

 small and so essential a part of foodstuffs. As these sub- 

 stances are destroyed by heating to 170 F. and are removed by 

 modern milling processes, it is obvious that great danger lies 

 in diets restricted to tinned food and white bread. Our supplies 

 of fresh natural foods must be maintained. Frightful suffering 

 and loss of life have been caused by the polishing of rice, a 

 milling process introduced merely to make the rice white and 

 please the eye of the buyer. This rice indeed has proved a 

 whited sepulchre and it has taken years of work to trace home 

 the causation of beri-beri to it. 



AN EXPLANATION OF BERI-BERI 



(Dr. Casimir Funk) 



A substance has been isolated recently in what appears 

 to be a pure condition from rice-polishings, which it is sug- 

 gested should be named vitamine. It crystallises in colourless 

 needles, which melt at 233 ; the results of the single analysis, 

 which the amount of material at my disposal permitted, indicated 

 the formula C ]7 H 20 N 2 O 7 . The administration of this substance 

 (about o - 02 grm.) to pigeons suffering from polyneutritis (beri- 

 beri) effected a rapid cure. The small proportion obtained, 

 however, did not allow of many such curing experiments being 

 performed and as the substance was not recrystallised doubts 

 of its purity might be entertained. A confirmation of these facts 

 was therefore absolutely necessary. In the first instance yeast, 

 which is known to be curative, was chosen as the source of 

 the material, as it was likely to give a better yield than 

 rice-polishings. It was of great interest to see whether yeast 

 contained the same substance as rice-polishings or only an 

 analogous compound. It was found possible to prepare a sub- 

 stance apparently identical with that present in rice-polishings. 

 The substance occurs in the fraction containing the pyrimidine 

 bases, which are, in fact, more or less precipitated by the agents 

 used in separating it. 



