19 



very little protein as was shown by the practically negative 

 response to the biuret test. 



c. Osseoalbumoid was prepared as before. An attempt 

 was made to obtain a product at an earlier stage in the prepara- 

 tion process than that of the preceding experiment. The 

 product had the same fluffy characteristic as before, only 

 it had a blood-red color. 



This crude osseoalbumoid was subjected to the peptic con- 

 ditions of the previous experiment. Digestion was started 

 at 9.45 A.M. 



10.35 A - M - Heating a portion of the filtered digestive 

 liquid failed to cause turbidity in it. 



10.50 A.M. Heating a portion of the filtered digestive liquid 

 failed to cause turbidity in it. 



11.05 A - M - A portion of the digestive fluid was withdrawn 

 and saturated with (NH 4 ) 2 SO 4 in the cold. A yellow sticky 

 precipitate was formed. It was completely soluble in warm 

 water. No precipitate was formed on heating this solution. 

 A portion of the solution was saturated with (NH 4 ) 2 SO 4 at the 

 boiling temperature. A precipitate was formed, which was 

 soluble in water but gave no precipitate on heating. 



11.30 A.M. About 1/8 of the original bulk of material 

 remained undigested. It was filtered off and subjected to 

 the action of a fresh pepsin-acid solution. 



This residue did not, however, undergo digestion on further 

 treatment with pepsin-HCl and looked like hematin. It was 

 soluble in Na 2 CO 3 from which solution it could be precipitated 

 by acidifying. Its solution gave the spectroscopic lines of 

 acid hematin. 



The nitrate from the undigested material was saturated 

 with (NH 4 ) 2 SO 4 in the cold. The precipitate had a reddish 

 color. The filtrate from this precipitate was saturated with 

 (NH 4 ) 2 SO 4 at the boiling temperature. Each of these precipi- 

 tates was dissolved in water. Samples of the solutions 

 were gradually heated with the results indicated in the 

 summary on the next page. 



