186 EXPERIMENT STATION RECORD. 



Perewozudkoff, Will, Ewald, Munk, and Lebedeff also attempted to 

 solve this j^roblem. These investigators were particularly interested 

 in the transformation of fatty acids in the animal body. Radziejewsky 

 fed a dog with mutton-tallow soap, and found that 88.5 per cent of the 

 amount fed was assimilated. Perewoznikoff,^ who fed a dog a mixture 

 of glycerin and fat-free soap, and also injected in the duodenum of the 

 dog a mixture of soap and glycerin and a soap solution without glyc- 

 erin, found that fat might be formed in the mucous membrane from 

 soap and glycerin. 



In experiments made with live frogs and frog muscles, WilF observed 

 the transformation into fat of chemically pure palmitic acid with and 

 without glycerin, and also of saponified palmitic acid. I. Munk,^ who 

 also furnished proof that fatty acids as well as fats are ijrotectors of 

 protein, fed a dog lard and the fatty acids made from it. He showed, 

 further, that the fatty acids which are generally absorbed as an emul- 

 sion are for the most part changed into fat by synthesis with glycerin. 

 A. Lebedeff^ fed a dog tributerine for a long time, but none of this sub- 

 stance was found stored up in the organism. However, Lebedeff^ soon 

 reported other experiments in which dogs were fed linseed oil and mut- 

 ton tallow and these substances were found in their organs and tissues. 

 I. Munk^ repeated these experiments of Lebedeff with all possible pre- 

 cautions and confirmed his results. Further, the same investigator 

 confirmed the synthesis of fatty acids of the food to neutral fats which 

 he had discovered in an investigation of the chyle. Experiments were 

 made with a dog which had fasted until the body contained no fat. In 

 one experiment he fed erucic acid, and in another the fatty acids 

 which are obtained from mutton tallow, and in each case observed a 

 considerable dei)osit of the corresponding neutral fats. Finally, in 

 1890, Munk, together with liosenstein, confirmed this synthesis by 

 investigations of normal human chyle, which was obtained through a 

 cannula. 



The formation of fat in the ripening of cheese and the making of wax 

 by bees were soon shown to be proofs of the new view regarding the 

 formation of fat from carbohydrates. Nadina Sieber''' investigated 3 

 sorts of Roquefort cheese in different stages of ripening. The results 

 of the analyses showed that the ripening consisted of a loss of water 

 and the decomposition of i)rotein, but did not include an increase of fat. 

 O. Kellner,^ who studied the ratio of fat to the constituents of the 



iCentbl. med. Wissensch., 1876, p. 851. 

 spfliiger's Arch. Physiol., 20 (1879), p. 255. 



^Verhandl. physiol. Ges. Berlin, 1879, No. 13, p. 94; Virchow's Arch. path. Anat. 

 iind Physiol., 80 (1880), p. 10. 



"Ztschr. physiol. Chem., 6 (1882), p. 149. 



sCentbl. med. Wissensch., 1882, No. 8, p. 129, 



6Du Bois-Raymoud's Arch. Anat. tind Physiol., 1883, p. 273. 



7 Jour, prakt. Chem., ser. 2, 21 (1880), p. 203. 



sLandw. Vers. Stat., 25 (1880), p. 39. 



