HUMAN CHYLE. 155 



The estimation of the total nitrogen was made by Kjeldahl's method. 

 5 c.c. of the chyle was found to contain '0182 gms. of nitrogen or '364? 

 gms. of nitrogen per 100 c.c. of chyle. 



Nitrogen in the filtrate after treatment with trichloracetic acid. 100 c.c. 

 of a 10 % solution of trichloracetic acid in water were added to 100 c.c. 

 of the chyle and the precipitate which formed was filtered off. The 

 nitrogen in 25 c.c. of the filtrate was determined by Kjeldahl's method 

 and was found to be '0014 gms., or '0112 gms. of nitrogen per 100 c.c. of 

 chyle. Another portion of the filtrate was acidified with hydrochloric 

 acid and treated with phosphotungstic acid. No precipitate occurred, 

 showing the absence of such nitrogenous substances as peptones and 

 diamino-acids. Thus by far the greatest part of the nitrogenous 

 constituents of the chyle are precipitable by trichloracetic acid. The 

 very small amount of nitrogen not so precipitated is probably due to 

 traces of some simple amide such as urea, since a slight evolution of gas 

 occurred when the filtrate from the trichloracetic acid precipitate was 

 treated with a solution of sodium hypobromite. 



For the estimation of Lecithin two samples of chyle collected during 

 a period of 24 hours were mixed together. The amount of phosphorus 

 in the ether extract obtained from this chyle was taken as a measure of 

 the quantity of lecithin present. The method employed for estimating 

 the phosphorus was a modification by Bayliss and Plimmer (1) of 

 Neumann's original method (28) . I found that the oxidation of the fat 

 proceeded more rapidly when the nitric acid was added frequently and 

 in small quantities as the mixture darkened in colour than when larger 

 quantities at longer intervals were used. Two determinations gave the 

 following results : 



N 



(1) 3'460gms. of ether extract required 10'2c.c. ^ NaOH. 



Z 



N 



(2) 2'163gms. of ether extract required 6*5 c.c. -= NaOH. 



Z 



which is equivalent respectively to: 



(1) 12-93 mgs. of P 2 O 5 = '370 gms. P 2 O 5 per 100 gms. of ether 



extract. 



(2) 8-24 mgs. of P 2 5 = "371 gms. P 2 O 5 per 100 gms. of ether 



extract, 



or, 4'204gms. of lecithin per 100 gms. of ether extract. 



Cholesterin. 4'320 gms. of ether extract were taken and saponified 

 by heating with alcoholic potash. The mass was evaporated to dryness 



103 



