176 Report of the Chemical Department of the 



Hcxon bases. — The phosphotungstic acid precipitate was de- 

 coiiiposcd by barium oxide, the barium hydroxide was removed 

 from the filtrate by sulphuric acid and then arginine and 

 histidine were precipitated by silver sulphate in barium hydrate 

 solution in the usual way. 



(i) Arginine. — After the separation of histidine from arginine, 

 a determination of nitrogen in the remaining solution indicated 

 the presence of about 1.5 grams of arginine, which is by far 

 the largest amount we have ever succeeded in separating from 

 any cheddar cheese with which we have worked. The solution 

 was evaporated, dilute nitric acid added and then set aside for 

 crystallization. After standing about a week, the solution had 

 partly crystallized. These crystals were removed by filtration, 

 washed with absolute alcohol and ether and dried over sulphuric 

 acid in vacuo. Analysis gave the following result: 



Calculated for arginine nitrate. Found. 



(CoH,, N,0, HNO3 1H,0) 



N 28.45 28.32 



To the mother-liquor was added silver nitrate with 2 or 3 drops 

 of dilute nitric acid and the solution was allowed to evaporate 

 in vacuo. Crystals soon separated and after a few days the entire 

 mass was crystalline. The crystals were washed with alcohol and 

 ether and dried over sulphuric acid in vacuo. A silver determina- 

 tion gave the following results: 



Calculated for arginine silver nitrate. Found. 



(Co H,, N, O, AgNo^ HNO3) 



Ag 26.54 26.49 



We believe we are justified in regarding this substance beyond 

 question as arginine. So far as we are able to learn, this is the 

 first time arginine has been separated from a ripening cheese; 

 and, in this case, we succeeded only when all biological factors 

 had been eliminated. 



(2) Histidine. — This base was separated as a di-chloride. 

 Analysis gave the following results: 



Calculated for histidine hvdrochloride. Found. 



(Co Ho N, Oo 2HCI) 



CI 31. 1 1 31.08 



N 18.42 ^8-59 



