Power of Crystalline Ovalbumin and Serum Albumin. 21 



same phenomenon of a primary drop in rotatory power followed by a slow rise 

 was observed as recorded in Table V : — 



Table V. 



Time interval. 



Temperature. 



P 



H. 



BE. 





° C. 







o 





15-0 



4 



85 



-4-25 





16 -0 



4 



85 



-4-26 





15-0 



9 



15 



-3 -94 





15-0 



9 



15 



-3-94 



1 day 



15 -0 



9 



15 



-3 95 



2 days 



15 -0 



9 



15 



-3-96 





15-0 



9 



15 



-3-99 



Experiment 3. — The effect of both acid and alkali was demonstrated by 

 means of the addition of very small quantities of HC1 and NH 4 OH and the 

 rotations observed are recorded in Table VI : — 



Table VI. 



Time interval. 



Temperature. 



Ph. 



an. 



Mb. 





° C. 





• 



o 





11 



5 -3 



-4-22 



-31 -89 





11 



7-5 



-4-07 



-30 -76 





11 



7-5 



-4-08 



-30 -83 



2 hours : 



11 



7-5 



-4 -08 



-30 -S3 





12 



7-8 



-4 10 



-31-00 



1 day 



12 



7-8 



-4 22 



-31 -89 





12 



4-8 



-4 -40 



-33 -25 





12 



4-8 



-4-40 



- 33 -25 



2 days 



13 



4-8 



-4-41 



-33-33 



The effect of the addition of alkali is most interesting and the prompt fall 

 in the rotation followed by a slow rise to the original value is distinctly 

 suggestive of a tautomeric equilibrium. I have observed this same pheno- 

 menon in the case of denatured serum albumin. The effect of increasing the 

 hydrogen ion concentration of the solution is an instantaneous increase in the 

 rotatory power, which remains constant at the new level. 



The experiment was repeated in order to discover at what P H the change 

 in the rotatory power occurred, and to discover further if the change were 

 reversible from either side of the isoelectric point. The observations are 

 recorded iu Table VII : — 



