52 



MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



By coacentratiug the solution decanted from A, on cooling, lie obtained a second precipitate, 

 " B," The filtrate from B by similar treatment yielded a third precipitate, " C." 



These three precipitates showed thesaniebehaviorwith various reagents and appeared to dili'er 

 only in their degree of purity. The reactions agreed with those of gliadin from wheat, which, re- 

 cording to Eitthausen, contains 18 per cent of nitrogen. 

 Kreusler found that — 



A contained 16.L'2 jier cent of nitrogen. 

 B contained 16.21 per cent of nitrogen. 

 C contained 15.36 per cent of nitrogen. 

 These three preparations were united, dissolved in dilute acetic acid, and fractionally precipi- 

 tated by dilute potash. Thus were obtained three precipitates — 

 I with 16 per cent of nitrogen. 

 II with 16.51 per cent of nitrogen. 

 Ill was too small in amount for analysis. 

 By this treatment the substance was separated into two portions of difierent nitrogen content 

 Kreusler in the next place prepared a new extract with alcohol of 80 per cent from 5 pounds 

 of ground oats, concentrated the solution until nearly all the alcohol was removed, and on cooling, 

 and treating the precipitate with ether and absolute alcohol and drying over sulphuric acid, 

 obtained 30 grams of substance having propeities like the former preparations, but not wholly 

 soluble in acetic acid. This precipitate contained 15.36 per cent of nitrogen. When it was heated 

 with acetic acid, a residue was left having 14.81 per cent of nitrogen. The acetic-acid solution 

 by three iiartial precipitations with dilute potash gave, as before, precipitates I, II, and III — the 

 third being too little for analysis. The composition was — 



Carbon . . . 

 Hydrogen . 



Nitrogen .. 



I 53.41 



I 7.15 



16. 99 ; 17. U 



This treatment, however, had failed to yield a product having as much nitrogen as Eitthausen's 

 gliadin. 



I and II were, therefore, united and dissolved in 60 per cent alcohol at a gentle heat. The 

 solution was brownish yellow, and on cooling a part of* the substance precipitated. The filtrate 

 from this precipitate gave a second precipitate when treated with absolute alcohol. These precipi- 

 tates were united and called A. The alcoholic filtrate contained a considerable amount of sub- 

 stance, which was separated by concentration and gradual precipitation with absolute alcohol. 

 This precipitate was marked B and resembled A in appearance. They contained — 



Since the substance was precipitated in the presence of a considerable amount of acetic acid, 

 and might be thought to retain some of the latter, the just-described process was repeated with A, 

 andpota.sh added to perfect neutralization. The precipitate thus obtained was slightly washed with 

 water, and after dissolving in 60 percent alcohol was precipitated with absolute alcohol. B was 

 dissolved du-ectly in weak, and precipitated by absolute alcohol. These products then had the 

 following composition: 



Carbon 52.94 



Hydrogen 7. 71 



N"-g- ■ \ I'Jiil 



