PREPARATION OF CHOLESTERIN. 425 



so as to saponify any fat. After the evaporation of the alcohol the choles- 

 terin is extracted from the residue with ether, by which the soaps are 

 not dissolved; filter, evaporate the ether, and purify the cholesterin by 

 recrystallization from alcohol-ether. The cholesterin may be extracted 

 with fat from tissues and fluids by first extracting with ether and then 

 proceeding as suggested by HITTER. J The essential points in his method 

 consist in saponifying the fat with sodium alcoholate, removing the alcoho 

 by evaporating to dryness with NaCl, and finally extracting the dried, 

 pulverized mass with ether. After evaporating the ether the residue is 

 dissolved in as little alcohol as possible and the cholesterin precipitated 

 by the addition of water. It is ordinarily easily detected in transudates 

 and pathological formations by means of the microscope. 



1 Zeitschr. f. physiol. Chem., 34. 



