Vitamine Measurement. 



219 



two 191 3 preparations were active, though one was markedly 

 more so than the other, and that the 191 2 preparation was in- 

 active. These specimens were supplied by Dr. Funk and represent 

 the products of greatest purity as obtained by his fractional 

 precipitation method. The only known impurity present was 

 nicotinic acid and pure synthetic nicotinic acid failed to respond 

 to the test. 



(6) Lloyd's reagent was shown by Seidell and Williams to 

 remove the B vitamine and by Harden and Silva to have little 

 if any action upon the C vitamine. This point was tested with 

 the new method and orange juice obtained by sterile puncture 

 was shown to be deprived of its powers of responding to the 

 test by shaking with the Lloyd reagent. This showed that the 

 reagent removes the cause of the test reaction. Through the 

 kindness of Mr. La Mer working in Professor Sherman's laboratory 

 orange juice shaken with the Lloyd reagent and then filtered, 

 was used in the treatment of a guinea pig suffering from scurvy. 

 The filtrate was curative in fifteen days. It was also used as a pro- 

 tective agent in the diet of a pig started on a scurvy-producing diet. 

 The symptoms had not appeared in twenty days. From these 

 two experiments we can conclude that the test is not affected by 

 the C vitamine and that the cause of the response is removed by 

 Lloyd's reagent. The power of the Lloyd reagent to remove the 

 cause of the test was confirmed by experiments with other vitamine 

 extracts. Such experiments are not conclusive evidence but since 

 the effects are so striking and the Lloyd has been demonstrated 

 to remove the B type they seem to justify the belief that the caus- 

 ative agent in the test is the anti-neuritic or water voluble B 

 vitamine. 



(c) Results were also presented showing that the test is appli- 

 cable to blood. Specimens of blood plasma furnished by Dr. 

 N. R. Blatherwick representing bloods from the jugular and the 

 mammary veins of a cow were poured into alcohol, the alcohol 

 filtered off, evaporated to dryness and the residue taken up with 

 enough water to restore it to the original plasma volume (10 c.c). 

 Repeated tests showed the mammary vein plasma residue to be 

 markedly richer in the B vitamine than that from the jugular veins, 

 indicating drainage from a mobilizing (?) point of the vitamine. 



