VISCOSITY 

 TABLE XLII 



211 



This demonstration completes the proof that the viscosity of 

 suspensions of powdered gelatin in water of different pH is 

 influenced in the same way by electrolytes as is the viscosity of 

 solutions of the same gelatin salts, and that this influence is due, 

 in the case of suspensions, to the influence of the Donnan equilib- 

 rium upon the swelling of the particles. 



The volume V of gelatin occupied in 100 c.c. of the suspension 

 was determined by filtering and deducting the volume of the 

 filtrate from the total volume of the suspension. Knowing 

 the viscosity we can calculate Einstein's constant c according to 

 the formula 



.. - c 



l V 



c should be 2.5 if V is sufficiently small. 



TABLE XLIII 



