BV JAMES M. PETRIE. l49 



was precipitated by 9 cc. of Mayer's reagent.* This precipitate 

 was decomposed with sodium sulphide, and the alkaloid obtained 

 as hydrochloride. The solution was made alkaline with ammonia, 

 and shaken out three times with chloroform. The chloroformic 

 solution was evapoi-ated in a weighed dish. The weight of 

 alkaloid obtained was 0-0536 gm. 



(b) 100 gms. of bark were extracted with hot alcohol as 

 before. After removing the spirit, the residue was treated 

 with water, and the resins filtered off. The small amount of 

 tannin was separated by lead acetate, and the alkaloid ob- 

 tained by precipitation with ammonia. The alkaloid which 

 still remained in solution, was removed by agitating with chlo- 

 roform, and added to the precipitate. The latter was then 

 dissolved in alcohol, excess of standard acid added, and then 

 titrated back to the neutral point with alkali, using sensitive 

 litmus as indicated. Required 16-3cc. ^ acid. 



(c) 10 gms. were treated as before, and the alkaloid obtained 

 by agitating the aqueous solution with chloroform. The latter 

 was evaporated, and the residue, which weighed 0*149 gm., was 

 titrated. Required 1'55 cc^i^ acid. 



Results : — (b) i6"3cc. rjr sulphuric acid. 

 ic) 15-5 



iTiean 159 cc. =00786 gni. sulphuric acid. 

 49 acid : 343 alkaloid : : 0-0786 : 0-55 

 therefore amount of alkaloid in bark... =0'55 by titration. 



0-536 by weighing. 



calculated on air-dried bark, mean 54% 



and calculated on material dried at 100°C. 063% 

 Alkaloid ill f/ie Leaves and Fruit. — Samples of the bark, 

 leaves and fruit were examined simultaneously by method 

 (a). After distilling off the alcohol, and extracting with 

 acidulated water, they were each titrated under the same con- 

 ditions, with Mayer's reagent. The volumes required were 



* Potassium mercuric iodide. 



