252 CHAMBERLAIN AND VEDDER. 



This strikes a hard blow at the idea that the lack of phosphorus 

 compounds is the cause of beriberi or polyneuritis gallinarum.* However, 

 there is still a possibility that the remaining 15 per cent of phosphorus 

 in some particular combination is the important element. We believe 

 that our work disposes of even this possibility, and that, as a result, 

 the idea that multiple neuritis of fowls is due to a deficiency of 

 phosphorus compounds must be abandoned. 



Our first step was to analyze this filtrate of Fraser and Stanton 

 for inorganic constituents, and we found that it contained 0.18583 

 per cent magnesiran phosphate and 0.01766 per cent of potassium 

 phosphate. 



In a previous paper from this laboratory Kilbourne(l) had suggested 

 the possibility that potassium salts might bear some relation to the 

 production of beriberi and subsequently an attempt was made by this 

 Board (5) to settle the point by feeding one group of fowls on polished 

 rice plus potassium. chloride, another groups on polished rice plus phos- 

 phoric acid, and a third group on polished rice with the addition of 

 both potassium chloride and phosphoric acid. These experiments were 

 completely negative and the fowls receiving these substances developed 

 neuritis as promptly as fowls receiving polished rice alone. 



In sj)ite of these discouraging results and the statement by Schau- 

 ■ mann ( 2 ) that the inorganic salts can have nothing to do with the preven- 

 tion of neuritis, we determined to give thes6 salts a more thorough trial for 

 the following reasons : First, we had demonstrated the presence of mag- 

 nesium and potassium phosphate in an extract that was proved to 

 prevent neuritis, and, therefore, even if these salts gave negative results, 

 their elimination would further simplify the problem and would prove 

 that a part at least of the 15 per cent of phosphorus found in the 

 filtrate of Fraser and Stanton was not concerned in the prevention of 

 neuritis of fowls. Second, we had observed in various analyses of rices 

 and rice polishings that the potassium content varied in the same 

 manner as the phosphoiais content and appeared to be just as good an 

 index of its neuritis-preventing or neuritis-producing power. 



The following experiment was performed for this purpose. Four 

 groups of fowls, each group consisting of four birds, were fed on 

 polished rice. In addition, Grroup A received daily 0.07 gram of 

 potassium phosphate; Group B received 0.07 gram potassium citrate; 

 Group C received 0.07 gram potassium carbonate and Group D received 

 0.07 gram magnesium phosphate. These salts were administered in 

 the dose of 0.07 gram because analyses showed that this amount was 



" The view that phosphorus was the essential neuritis-preventing element has 

 been especially advocated by Schaumarm.(2) but not by Fraser and Stanton who 

 were particular in stating that the amount of phosphorus pentoxide was only 

 an indicator of the neuritis-produ.cing power (3) of the grain. 



