HY JAMES M. PETRIE. 113 



(5) Seeing the effects of two successive hydrolyses, in de- 

 composing certain of the constituents, to be so marked, the 

 following series was designed to show the effect of varying 

 the conditions of hydrolysis. For this purpose, a solution 

 was obtained by the method described in paragraph 1 (b), 

 and was further treated in the following manner. The liquid 

 was made to contain 5% (by weight) of sulphuric acid, and 

 a solution of phosphotungstic acid was added till no further 

 precipitate formed on standing. The clear fluid was decanted, 

 and the rest separated by the centrifuge, the precipitate 

 being washed with the dilute reagents. From the fluid, the 

 reagents were removed by baryta in slight excess, and the 

 latter by carefully titrating with sulphuric acid, till the 

 colour with phenolphthalein was just removed. After filtra- 

 tion, the clear pale yellow fluid was divided into five equal 

 portions for hydrolysis, as follows: — 



a. Boiled for i hour with 8% (by wt. ) hydrochloiic acid. 

 h. ,, 2 hours ,, 8 ,, ,, 



r 4 S 



">• 11 8 ,, ,,8 ,, ,, 



c. ,, 15 ,, ,, 25 ,, sulphuric acifl. 



The hydrolysed fluids were then each neutralised, and 



distilled with magnesia by a current of steam into standard 



acid. The distillate was titrated after every hour, for four 



consecutive hours, and gave the following figures : — 



11-85 12-10 13-86 16-45 310% 



per cent, of the non-protein N in the extract. 



Results. — In the above extract, after phosphotungstic acid 

 precipitation, the process of hydrolysing decomposes some of 

 the constituents, with the liberation of ammonia. The 

 quantity of ammonia set free increases with the length of 

 time the solution is boiled, and also with the strength of the 



