DISEASES OF UNKNOWN ETIOLOGY 439 



ing rice opened the way for a vast amount of experimental work. As regards the 

 nature of the neuritis preventing substance in the rice polishings it was soon found 

 that it had no relation to the phosphorus content. Funk has isolated a substance 

 he calls vitamine, a pyramidine base precipitated by phosphotungstic acid, which is 

 present in rice in the proportion of i to 100,000 and seems to possess extraordinary 

 curative properties in polyneuritis gallinarum. Heart muscle, egg yolk and yeast 

 are rich in this anti-neuritis substance, which is also present in lentils and barley. 

 Schaumann considers malt as richer in the anti-neuritis vitamine than any other 

 article of diet, rice bran coming next. Many think that vitamines have not as yet 

 been separated but that they are intimately combined with some mother substance 

 in the food. There is, in all probability, a large number of vitamines present in 

 various animal and vegetable foods, the deficiency of which in a diet may lead to 

 vague disorders or to well-recognized diseases, such as scurvy, ship-beriberi, beriberi 

 or pellagra. 



Schaumann considers the curative principle to be of the nature of 

 an activator. An increase in the ingestion of carbohydrates and nec- 

 essarily in the vitamine as well seems to produce neuritis more rapidly 

 than where a smaller amount is given, this indicating the importance 

 of these vitamines in carbohydrate metabolism. 



In epidemics of beriberi it has been observed that those who eat most rice are more 

 often attacked, thus men more frequently than women. A temperature of 1 2oC. de- 

 stroys the vitamine. Owing to the absence of rice as a constituent of other than slight- 

 est importance in the dietary of Brazilian cases of beriberi, as well as from numerous 

 reports of the occurrence of the disease in nonrice-eating persons, the view that is 

 now entertained is that not only polished rice, but any predominating carbohydrate 

 article of diet, which is deficient in the neuritis-preventing substance, can produce 

 beriberi. Wellman and Bass have shown that such articles of diet as sago, boiled 

 white potatoes, corn grits and macaroni practically parallel polished rice in the pro- 

 duction of polyneuritis in fowls. 



Blackwater Fever. Considered as a malarial disease, but thought by 

 some to be possibly caused by a protozoon a Babesia (Piro plasma). 

 A disease usually occurring in patients with a malarial history and 

 characterized by rapid febrile onset, early jaundice, asthenia, pain in 

 loins and the pathognomonic haemoglobinuria. 



Dengue. Supposed to be due to a protozoon transmitted by Culex 

 fatigans. A disease characterized by sudden onset, high fever for three 

 or four days, pains in the postorbital regions, back and about joints. 

 A remission occurs on the third to fifth day followed by a secondary 

 rise of temperature and a measles-like eruption. Leukopenia and re- 

 duction in the percentage of polymorphonuclears. Virus exists in 

 the blood and is filterable. 



