EXPERIMENTAL. 77 



The aqueous layer was heated with an excess of barium hydroxide on a 

 water-bath for 5 hours. After standing some time, the barium salt that had 

 separated was filtered out and decomposed by an equivalent amount of sul- 

 phuric acid. The solution on concentration yielded 5.76 grams of aspartic 

 acid. 



Carbon and hydrogen : 0.3866 gram substance, dried at 110, gave 0.5 109 gram CO 2 and 



0.1852 gram H 2 O. 



Nitrogen : 0.3637 gram substance gave NH 3 = 3.78 cc. HC1 (i cc. HC1 = o.oi gram N). 

 Calculated for C 4 H 7 O 4 N, C 36.09, H 5.26, N 10.53 P- ct. ; found, C 36.04, H 5.32, N 



10.39 P- ct - 



The filtrate from the barium aspartate was freed from barium, concen- 

 trated to small volume, and saturated with hydrochloric acid. On prolonged 

 standing a trace of phenylalanine hydrochloride separated, but no glutaminic 

 acid hydrochloride was obtained. After removing the hydrochloric acid 

 with silver sulphate and the sulphuric acid with barium hydroxide, the 

 solution was boiled with an excess of copper hydroxide, but no copper salt 

 could be separated from it, even after concentrating to a very small volume. 

 The copper was then removed and the solution treated with bone-black and, 

 when concentrated in a vacuum over sulphuric acid, gave crystals which, on 

 fractional crystallization from water, gave 0.42 gram of serine, which, in 

 an open capillary, browned at about 218 and decomposed to a brownish 

 mass at about 240. 



Carbon and hydrogen: 0.2577 gram substance, dried at 110, gave 0.3224 gram CO 2 



and o. 1602 gram H 2 O. 

 Calculated for C 3 H 7 O 3 N, C 34.24, H 6.73 p. ct. ; found, C 34.12, H 6.91 p. ct. 



In the filtrate from the serine there was obtained about 5.32 grams of crys- 

 talline substance, from which nothing definite could be isolated. 



DISTINCTION RESIDUE. 



The residues from distillations A and B were dissolved in boiling alcohol 

 and the solutions united. On cooling, 5.76 grams of long hair- like crystals 

 separated. 



The filtrate from this substance was freed from alcohol and saponified by 

 heating with 200 grams of crystallized barium hydroxide, the barium re- 

 moved, the solution concentrated under reduced pressure to small volume, 

 saturated with hydrochloric acid, and, after standing on ice for some time, 

 yielded 74.21 grams glutaminic acid hydrochloride, equal to 59.46 grams. 1 



The glutaminic acid hydrochloride melted at about 198 with effervescence. 



Carbon and hydrogen : 0.4028 gram substance, dried over H 2 SO 5 , gave 0.4802 gram 



CO 2 and 0.2056 gram H 2 O. 

 Calculated for C 5 H 10 O 4 NCI, C 32.67, H 5.50 p. ct. ; found, C 32.51, H 5.67 p. ct. 



^bderhalden & Wells, Zeitschrift fur physiologische Chemie, 1905, xi<vi, p. 31. 



