JilOLl^GICAL CLASSII ICAIIOX Ol- loOUS .51 



purified protein fcasein), milk-sugar fsupjjoseflly j)ure). salts in 

 imitation of the mineral matter of milk, and milk-fat. They 

 coulfl see no reason wh}- the polished riee. supjplemented b}' j)uri- 

 tied j)rotein, suitable salts and milk-fat shoukl not be a comi)lete 

 food. This was cleared up subsequent]\' b\' establishing the 

 fact that the milk-suL'ar u>f(\ in the former of these two experi- 

 ments, and the germ or chit of the cereal seeds, which had been 

 rubbed off the rite, contain a water-holubk' substance essential for 

 growth, health anrl \i'gor. 



The conclusions hnalh' reached were, hrst, that amongst 

 the foofl substances 'jjrotein, carboln'drates and ash (jr mineral 

 matter) coming Irom ditlerent sources there is a marked dilter- 

 ence in quality, and that those from milk are ol a axt}' high order; 

 and second, that there are two as \'et unidentified substances 

 which are indispensable to gr(nvth and health, namely, the 

 unkn(Avn substance which is pre>ent in milk-fat. the fat ol yolk oi 

 egg and some of the glandular lats, which McCollum and Ken- 

 nedy subsec[uentl\- designated " fat-soluble A," and a second 

 substance soluble in water, which the\' designated " water- 

 soluble B." The absence oi the former (fat-soluble A) n(jt (jnly 

 prevents growth, but also causes a serious e\'e troufjle which, if 

 not corrected in time, will end in blindness and death. \\c hnvt 

 already illustrated this jioint. The absence of the water- 

 soluble alsi; pre^•ents growth, and causes serious j)hysiological 

 disturbances resulting in a fonn of paral_\'sis, beri-beri. which is 

 quite prevalent where such f)ods as polisherl rice and bolted 

 flour form the main article of diet. 



But this water-soluble is present in most orrlinary food 

 substances, anrl particular!}' in a mixed diet, whereas the sources 

 of the fat-soluble are quite limited, the fat of milk, in the form 

 of milk and butter, being the chief of these. 



In support (jf what has been said, the utterances of some of 

 our leading physiologists anrl students of nutrition may be 

 cjuoted. 



Dr. H. C. Sherman. Professor of Food Chemistry. Columbia 

 University: " E.specially in the feeding of chiklren should milk 

 be used freelv. because of its man\- advantages as a tissue- 



