HISTORICAL SURVEY 33 



Research on the preparation of the active substance from rice 

 polishings were also conducted by Tsuzuki (66), but with little suc- 

 cess. Owing to the enormous content of phytin in rice bran, Aron 

 and Hocson (67) believed that it was curative; the good results they 

 obtained may be explained by the probability that the phytin was 

 contaminated by some of the active substance. Research on phytin 

 had already been carried out by Eijkman without results, and also 

 by Cooper and Funk (68). 



To summarize our knowledge of the chemical nature of the active 

 principle prior to the introduction of the vitamine theory (till 1911), 

 the following may be set down with certainty: 



1. The substance is soluble in water, alcohol and acidified alcohol. 



2. The substance is dialysable. 



3. The substance is destroyed at 130C. 



When we took up the question in 1911, it was not known whether 

 the active substance was organic or inorganic in nature, whether or 

 not it was a constituent of proteins, nucleins or phosphatides. It was 

 not certain that we were not dealing with a ferment, nor was it known 

 if the substance belonged to some chemical group already described, 

 or to some new unknown class of substances. We shall be in a 

 position to answer a good many of these questions during the course 

 of our discussions. 



