144 LEUCINE. 



water, treat with pure and good animal charcoal, filter, 

 and evaporate filtrate till a pellicle begins to form, 

 then pour the boiling hot solution into three or four 

 times its volume of absolute alcohol. Allow to stand, 

 collect on a filter, and press between filter paper; 

 perfectly white leucine is thus obtained. 



4. Leucine is sparingly soluble in cold, but mode- 

 rately soluble in hot water, almost insoluble in alcohol ; 

 it dissolves in acids and alkalies. 



5. Heat gently a portion of leucine in a wide test 

 tube, it will sublime in snow-white flocks. Heat some 

 leucine on a piece of platinum, it will take fire and 

 burn with a white flame. 



6. Heat some leucine mixed with soda lime ; a 

 strong smell of ammonia is evolved, proving the pre- 

 sence of nitrogen. 



7. Dissolve leucine in water, pass nitrous acid gas ; 

 leucic acid is formed. 



8. Add to a solution of leucine a concentrated solu- 

 tion of sulphate of copper gradually until an excess of 

 copper is present ; the fluid takes a deep blue colour. 

 Treat the deep blue solution with an excess of baryum 

 carbonate, and filter ; on evaporation the compound of 

 copper and leucine is deposited in blue crystalline 

 granules. 



Luteine. I. From corpora luted of Mammals. 



1. Dissect out the corpora lutea from the ovaries 

 (of cows), pound the corpora, warm, and press 

 out the juice. 



