1910.] Destiny of Cholesterol in the Animal Organism. 56 i 



•dissolved in alcohol and precipitated directly. The results in the following 

 table were obtained, proving that, where one is dealing with pure chemicals 

 -at any rate, the method is accurate : — 



Table I. — Pure Cholesterol. 



Method of experiment. 



Amount of 

 cholesterol 

 (actual). 



Amount of 

 compound. 



Amount of 

 cholesterol 

 (found). 



Actual 

 difference. 



Direct precipitation — 



1. Weighings in Gooch crucible ... 



2. Weighed in tared filter paper . . . 



3. „ )) ••• 



0-01 

 O-OOl 

 0 01 



0 -0397 

 0 -0430 

 0 0413 



0 -00960 

 0 -00104 

 0 -01003 



-0 -00040 

 + 0-00004 

 + 0 -00003 



II. Experiments to ascertain how far concordant results could be obtained, 

 in the case of a substance containing a small amount of cholesterol, if small 

 quantities of material were used. For this purpose a specimen of beef suet, 

 which had been recrystallised several times by solution in ether and 

 precipitation by alcohol, was taken. It was practically free from cholesterol 

 •esters. The results are given in the following table : — 



Table II. 



Method. 



Weight 

 of fat. 



Weight 

 of 



compound. 



Weight of 

 cholesterol 

 (found). 



Chole- 

 sterol in 

 fat. 



Average 

 cholesterol 

 in fat. 



Difference 

 from 

 average. 



Direct precipitation — 

 Weighings in filter paper 



Saponification — 

 Weighings in filter paper 



0 -3156 

 0 -3134 



0 -3120 



0 0015 

 0-0015 



0-0014 



0 -00036 

 0 -00036 



0 -00034 



per cent. 

 0 115 

 0 -116 



0-109 



per cent. 

 0-113 

 0 113 



0 113 



per cent. 

 + 0 -002 

 + 0 -003 



-0 -004 



III. Experiments in which weighed quantities of cholesterol were added 

 to amounts of fat considerably in excess, relatively to cholesterol, of the 

 weight of the ethereal extracts usually obtained in our experiments on blood. 

 Duplicate analyses were made of the fat alone, and the fat to which measured 

 amounts of cholesterol were added. The results are given in the following 

 table : — 



