166 PHYSIOLOGICAL CHEMISTRY. 



a solution of caustic potash in alcohol so as to saponify any fat. 

 After the evaporation of the alcohol we extract the cholesterin 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 from tissues 

 and fluids by first extracting with ether and then purifying as 

 above. 



It is detected and determined quantitatively in tissue, etc., by 

 this same method. It is ordinarily easily detected in transudations 

 and pathological formations by means of the microscope. 



