250 HALOIDS AND HALOID BASES. 



chyle of a dog. The fat which was extracted with ether was oily, 

 was not precipitated from boiling alcohol on cooling, and was for the 

 most part saponifiable. 



This seems to confirm Schultz's observation,* that the fat of 

 the blood is more consistent than that of the chyle, and it may 

 further be remarked that the fats of the blood are mostly saponi- 

 fied or incapable of saponification, w r hile those of the chyle corres- 

 spond to the ordinary salts of oxide of lipyl. 



The excellent investigations recently instituted by Cl. Bernardf 

 have afforded the most striking proof that the fats are digested 

 by the pancreatic fluid ; i. e., that the fats are not reduced to an 

 emulsive state, either by the gastric juice, or (as BrodieJ believed 

 that he had found) by the bile, and thus fitted for resorption. But 

 the conclusion which Bernard would draw from an experiment in 

 which he found that fat had been converted into fatty acids and 

 glycerine by the action of the pancreatic juice, viz., that all fats are 

 converted by the process of digestion into glycerine and the corres- 

 ponding fatty acids, is controverted by the fact above referred to, 

 that the chyle contains, in comparison with the blood, much unsa- 

 ponified and but little saponified fat. 



Marchand and Colberg found oily and crystalline fat in the 

 lymph. 



The quantity of fat in the human body varies considerably at 

 different periods of life. Thus in the foetus we generally find no 

 fat, except a few small masses in the omentum and in the loins. 

 Infants prematurely born are rounder in form immediately after 

 birth than at a subsequent period, for as their organism is not fully 

 prepared for an atmospheric life, they soon become emaciated, and 

 lose much fat through the intestinal canal. The muscular tissues 

 of the heart and face are found to be copiously furnished with fat 

 even at this early period. New bom children are in general tolerably 

 plump and roundish, and have a considerable quantity of fat de- 

 posited under the skin. The organism is most rich in fat during 

 childhood, but this deposition of adipose matter diminishes with 

 the development of the sexual functions, although it again increases 

 at a more mature period of life, and then occasionally acquires an 

 excess never observed at any other age. Extreme old age gradually 

 arrests this tendency to adiposity until it is completely destroyed 

 by marasmus senilis. 



* System der Circulation, 1836. S. 131. 



t Arch, gener. de rae'd. 4 Se'r. T. 19, pp. 60-81. 



Quart. Journ. of Science. Jan. 1823. 



