MIGRATION VELOCITY OF THE PROTEIN IONS 135 



capacity of dissolving the casein may be attributed is 

 diminished. Apart from the fact that Robertson's corrected 

 values still show clearly a tendency to decrease with increasing 

 concentration of alkali, no safe basis for the correction applied 

 by him exists at all. 



We give, therefore, the uncorrected, actual experimental 

 results of this author in the tables on p. 134. 



A glance at these results shows that, as a matter of fact, salt 

 I. (Table 72) exhibits half the electro-chemical equivalent of 

 salt II. (Table 71), as we should expect from the constitution of 

 the casemates. For the complex ion [casein (casemate''')] the 

 mean value of 23-7 mg. is obtained ; for the simple ion 

 (caseinate) "' the value of 11-15 m g- P er coulomb. If the 

 equivalent weight be calculated therefrom, taking 96,540 as the 

 number of coulombs required to transport i gm. equivalent of 

 an ion, we obtain 1,076 as the equivalent weight of casein 

 which has been taken to be about 1,000 in the preceding pages. 



These electro-chemical measurements, therefore, provide 

 valuable evidence in favour of the constitution of the caseinates 

 which we have previously assumed. 



