JACQUES LOEB 



251 



Regiori^of _ 

 GelatitvFeCNe 



Isoelectric _ , 



40 



30 



ZO 



10 



20.0 



17.5 



15.0 



12.5 



10.0 



7.5 



5.0 



lb 







300 



Z75 



250 



225 



200 



175 



150 



125 



100 



75 



50 



25 







4 



3 



2 



MCI 

 cone, used 



Turbid Clear 



M M N tj_H MtO MMMKIM 

 4 6 16 32 e>4 128 256 512 1024 20+6 40S6 8192 



pH 



4.9 5.Z 6.2 7.1 7.4 7.6 



-}|K4FeCN6 



Fig. 8. Gelatin treated with different concentrations of HCl, washed, then 

 treated with m/16 K4FeCN6, and then washed again. On the left, more acid side 

 from the isoelectric point, gelatin exists as insoluble gelatin ferrocyanide, with 

 low osmotic pressure, low conductivity, etc.; on the right, more alkaline side from 

 the isoelectric point, gelatin exists as potassium gelatinate with high conductivity, 

 osmotic pressure, etc.; at the isoelectric point, pure and sparingly soluble gelatin. 



