46 Miss H. Chick and Miss E. M. Hume. The Substance, the 



The modern " roller " milling of wheat effects so perfect a separation of the 

 constituent parts of the grain that trustworthy material for experiment is 

 readily obtained. During the " break " of the grain by the rollers the pericarp, 

 being brittle, is broken up into bran, while the embryo, being soft and oily, is 

 squeezed out flat. The subsequent operations of milling, which include such 

 processes as sieving, fanning and centrifuging, lead to a complete separation 

 of these two products. With rice, however, this is not the case, and the few 

 experiments we made with rice germ were made with materials separated by 

 hand in the laboratory. 



Methods Employed. 



Polyneuritis of birds has been accepted as analogous to beri-beri in human 

 beings with regard to etiology, symptoms, and methods of cure. The following 

 experiments were, therefore, made with pigeons of 300-400 grm. weight, and 

 were of two kinds, the methods adopted being in principle those used by 

 Cooper (1913 and 1914), working in this Institute. 



(1) Preventive, in which determination was made of the minimum amounts 

 of the various materials in question, that must be added to a (relatively) 

 vitamine-free diet in order to prevent the occurrence of polyneuritis. Polished 

 rice, about 40 grm. daily, formed the vitamine-free diet, and prevention was 

 considered to be successfully accomplished if the bird showed no symptoms of 

 polyneuritis after a period of about 60 days. Unprotected birds usually 

 developed symptoms in 15-25 days. 



(2) Curative, in which determination was made of the minimal amount 

 which, administered by the mouth, would cure a bird suffering from acute 

 polyneuritis. A bird in this condition, brought on by an exclusive diet of 

 polished rice, will usually die within 24-48 hours if not treated. In order to 

 be able to administer the requisite amount of curative substance ia time 

 Cooper {loc. cit.) concentrated the vitamines by extracting the air-dried 

 material with absolute alcohol in the cold and evaporating the alcoholic 

 extract to dryness under reduced pressure. This residue was taken up in a 

 small volume of water and definite quantities were given by the mouth, the 

 doses being reckoned in terms of the original foodstuffs. We found it possible, 

 however, in most cases, to give the curative doses of the original materials 

 without preliminary extraction. By this means we gained a better idea of 

 their absolute vitamine value in the natural condition, and avoided the loss 

 due to the extraction processes. Our method, however, has its drawbacks, as, 

 unless the crop of the bird is fairly empty at the time when a cure is essayed, 

 digestion and absorption will be slow and difficult. In addition, these 

 processes are frequently interfered with by the paralysis of the bird, so that 

 cures are often slow (24 hours to 3 or 4 days) in progress, and it is unusual 



