58 



MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



Mtrogen, I {Dumas method). — 0.5000 gram air-dried (=0,4554 gram, dried at 110° C.) gave 

 63.1 cc. gas at 10° C. (barometer 759.5 mm. at 16° C.)=16.53 per cent, less correctious 0.20=16 33 

 per cent N. 



Nitrogen, II.-^f)MQO gram (=0.4490 gram, dried at 110° C.) gave 02.42 cc. gas at 14° C. (ba- 

 rometer 770.3 mm. at 17° C.)=16.53 per cent N.; corrected =10.33 per cent N. 



Nitrogen, III. {Kjeldahl method). — 0.5000 gram (=0.4490 gram, dried atHQoC.) gave ammonia 

 =8.65 cc. nCl (1 cc. HCI=.00854 gTam N) =16.45 per cent N. 



Nitrogen, 7F.— 0.5000 gram (=0.4490 gram, dried at llOo C.) gave ammoiiia=8.70 cc. HC1= 

 16.54 per cent N. 



Stilphur, J.— 1.00 gram air-dried (=0.9107 gram, dried at 110° C.) gave 0.1850 gram BaS04, 

 whicb, when fnsed witli NajCOj and reprecipitated, gave 0.1495 gram BaSO4=0.020532 gram S = 

 2.25 per cent. 



Sulphur, II.— 1.00 gram (=0.9107 gram, dried at 110° C.) gave 0.1575 gram BaS04, wliich, wlien 

 fused with NaiCOj and reprecipitated, gave 0.1469 gram BaSO4=0.020175 gram S=2.21 per cent. 



These analyses are observed to agree closely with each other, as well as with several of the 

 preparations obtained under various conditions from the first extract already described, as is 

 shown by the following table : — 



Oat-proteid extracted hy wealc alcohol. 



* Not corrected for ash. 



The figures given by Kreusler for the nitrogen of two precipitates from his first alcoholic 

 extract are likewise in close agreement with the above, viz, 16.22 and 16.21 per cent. From his 

 " oat-legumin " Kreusler also extracted by means of alcohol a substance with 16.38 per cent 

 nitrogen. 



It seems hardly probable that such concordant analyses could result from impure prepara- 

 tions or fi-om a mixture of two or more proteids, especially in view of the varying conditions under 

 which the preparations were obtained. 



The very high content of sulphur is remarkable. No other analysis of a vegetable proteid 

 a]iproaches this amount. Ritthausen* found, indeed, in a single preparation from sesame press- 

 cake 2.36 per cent, but he attributed this high percentage to some foreign substaace precipitated 

 with the proteid. He afterwardst stated the percentage of sulphur as 1.25, and ascribed the high 

 figure fir.st obtained to calcium sulphate. Among the animal proteids besides Keratin, some forms 

 of human serum-albumin contain 2.3 per cent of sulphur.J: 



The fact that sulphur iu my analyses is 0.60 per ceut more than found by Kreusler in his 

 gliadin indicates that his substance had undergone chemical change during the processes of ]irep- 

 aration. 



Ritthausen believes to have obtained from wheat gluten by extracting with alcohol three 

 distinct proteids, to which he applies the names fibrin, gliadin, and mucedin, and he includes under 

 one or the other of these terms all the proteids soluble in alcohol which he and Kreusler found in 

 their extended study of the cereals. That portion of wheat gluten which is insoluble in alcohol 

 Ritthausen denominated gluten-casein. 



'Pfluger's Archiv. 21, 95 (1880). t J. iiiakt. Chom. 26, 414. \ Starke; Jsb. thier. Chu 



11, 19. 



