752 



CHARGE OF ISOELECTRIC PROTEIN BY IONS 



on the p.D. is identical for the same concentration of CI. This proves 

 that only the CI ion of these salts influences the p.d. of a gelatin 

 chloride solution of pH 3.0 and that the La ion does not increase the 

 P.O. of the solution. 



28 

 26 

 24 

 22 

 20 

 18 



I ^^ 



g 12 



10 

 8 

 6 

 4 

 2 



nJNLN.N.N:NMNMN 

 ^ 2048 1024 512 256 128 64 32 16 8 



Concentration of CI ions 



Fig. 1. Depressing influence of NaCl, CaCU, and LaCls on the p.d. between 

 a 1 per cent solution of gelatin chloride of pH about 3.0 and aqueous solutions 

 of the salts originally of the same pH, the two solutions being separated by collo- 

 dion membranes. Ordinates are the p.d., abscissae the concentrations of CI ions 

 of the salts. The depressing effect of the three salts is the same for the same 

 concentration of CI ions, proving that the cations do not influence the p.d. of 

 gelatin chloride solutions. 



