33^ Vitamines and Deficiency Diseases [June-September 



metabolism. It seems that the phosphorus could be dropped from 

 the combination without loss of advantage. 



Regarding the influence of cod-liver oil on calcium metabolism, 

 we find in the literature opinions that disagree with those of Schloss, 

 as in the case of Kurt Meyer (103), for example. In Osteogenesis 

 imperfecta (congenital porosity of bones) good results with cod- 

 liver oil were observed by Borkman (104), and with cod-liver oil 

 and hypophysochrom by Schabad (105). The discordant results 

 of various authors can be explained, perhaps, as we shall see later, 

 by the use of dissimilar preparations. 



The most important objection any one has advanced against the 

 vitamine-deficiency theory of the origin of rickets is the relative 

 frequency in the occurrence of rickets in breast-fed infants. This 

 fact seems to me to be one of the best arguments in favor of this 

 theory, as is indicated in the succeeding section. 



VIII. CHEMISTRY OF COD-LIVER OIL 



Exceedingly little work has been done on this subject. In 1888, 

 Gautier and Mourgues (106) isolated, by extraction and by distilla- 

 tion at a high temperature, two nitrogenous bases called by them 

 morrhuin and aselin. Judging from. the character of the methods 

 used, these substances may be regarded as secondary products result- 

 ing from the distillation, or as decomposition products of some more 

 complicated substances. A series of papers on this subject were 

 published by Iscovesco (107), who, working with the usual methods 

 for the preparation of Phosphatids, isolated a lipoid either from cod- 

 liver oil or from the liver of codfish. He claimed to have obtained, 

 with this preparation, a specific action on the growth of rabbbits and 

 guinea-pigs, which could not be duplicated with any other lipoid. 

 We shall consider, in the section on growth, the effects claimed for 

 this preparation. 



During the year 1914 I took up the subject. As a basis for my 

 investigation I relied upon the Observation, of several specialists in 

 children diseases, that more pronounced therapeutic effects have 

 been obtained with crude cod-liver oil than with the highly refined 

 pharmaceutic preparations. My experiments were made on young 

 chickens which, when kept under laboratory conditions, develop a 



