4 



U. SUZUKI. 



with water to a certain volume, and the determination of nitrogen 

 was made. The results were as follows. 



a )- 19.75 grams dry crude proteids (= 1.5825 g. N.) boiled 



with 2oj?Q HC1 for 30 hours. 



Total dissolved nitrogen. 1-54/6 100.0 



Nitrogen, in copper hydrate 



precipitate. 0.1040 6.7 



Nitrogen, directly precipitated by 



phospho-tungstic acid. 0.5506 35.6 



Nitrogen in phospho-tungstic 



precipitate in the filtrate of 



copper hydrate precipitate. 0.4316 28. C 



Nitrogen in ammonia. 0.1936 12.5 



Nitrogen in organic bases. 0.2380 15.5 



b)- 3-3 2 S- dry crude proteids ( = 0.2632 g. N.) boiled with 

 20% HCI for 96 hours. 



Total dissolved nitrogen. 0.2604 100.0 



Nitrogen in copper hydrate 



precipitate. 0.0158 6.1 



Nitrogen directly precipitated by 



phospho-tungstic acid. 0.0S84 34.0 



Nitrogen in phospho-tungstic 



precipitate in the filtrate 



of copper hydrate. 0.O/26 27.9 



Nitrogen in ammonia. 0.0335 12.8 



Nitrogen in organic bases. 0.0391 15.1 



We see from the above results that nearly 15^0 °^ 

 nitrogen in the proteids are found in the form of organic bases 

 (by the action of hydrochloric acid). No difference was 

 observed between 30 and 96 hours boiling, both yielding the 

 same result. 



Note: — The total amount of nitrogen was determine! by Kjeldahl's method. 



Nitrogen in copper hydrate precipitate was determined to see whether some proteids 

 or peptone still remain undecomposed, for this purpose the hydrochloric acid extract was 

 exactly neutralized with caustic soda and then a few drops of freshly precipitated copper 

 hydrate were added. The precipitate was collected on a filter, washed well, dried, and 

 the nitrogen determined. In this way, I always found that a small quantity of nitrogen 



