G. Williams 195 



this time together with about 50 c.c. of water. The distillate was strongly- 

 alkaline and fumed with concentrated hydrochloric acid. The Fraction 1 

 produced in the second distillation was saponified in the same way. 

 The two liquids were then combined, evaporated down, and the acids 

 dried in the oven until of constant weight. The weight of dry acids 

 obtained from the two fractions was 12-3 grms. 



« Fraction 2. 



These esters were saponified in the usual way by diluting with four 

 times their volume of water and boiling vigorously under a reflux 

 condenser for eight hours. The oily drops soon disappeared and the 

 reaction became neutral. Fraction 2 from the second distillation was 

 treated in the same way, and then combined with the other. The 

 weight of dry acids obtained from the two distillations (Fraction 2) 

 was 71-6 grms. 



Proline. 



The dry acids of Fractions 1 and 2 were placed in separate flasks 

 and absolute alcohol added to them. These were then warmed up and 

 kept at boiUng point for about ten minutes. After standing over 

 night the alcohol was filtered off through ordinary filters. The small 

 amount of solid on the papers was washed back into their respective 

 flasks by means of absolute alcohol. These extractions were repeated 

 twice again in exactly the same manner. 



The alcoholic extracts were evaporated down in vacuo at 40° C. 

 In order to dry the residues in the distilling flasks thoroughly, about 

 20 c.c. of concentrated sulphuric acid were placed in the distillate 

 flasks (after pouring ofi the alcohol which had come over) and the 

 vacuum maintained by clipping the side tubes. Absolute alcohol was 

 added to the dry residues, much sohd remaining undissolved. The 

 insoluble portions were filtered ofi and returned to their respective 

 flasks. The solutions were now evaporated to dryness in vacuo as 

 before, and the residues thoroughly dried. The dry residue from 

 Fraction 2 went up completely into cold absolute alcohol, but the 

 extract from Fraction 1 had to be retreated. Finally the two extracts, 

 perfectly soluble in cold absolute alcohol, were combined and made up 

 to 500 c.c. Kjeldahl determinations of the total nitrogen present in 

 the solution were made. 



10 c.c. gave NHg equal to 26*8 c.c. N/10 acid 

 = 0-03752 grm. N. 



500 c.c. contain 1-876 grms. N. 



