ALUMINIUM HYDROXIDE BY ELECTROLYTES. 



17 



An inspection of the foregoing table reveals the following 

 facts. Ill the eases where the coagulation takes place, the 

 relative viscosity shows a noticeable rise only when the con- 

 centration of the electrolytes reaches certain values. From this 

 point the viscosity increases with the increasing concentration to 

 a certain limit, and then ceases to be influenced by the further 

 addition of the electrolyte. Sometimes the increase of viscosity 

 with increasing concentration is gradual, while in other cases 

 it is quite sudden. Again the limiting value, to which the 

 relative viscosity tends, shows considerable difference in different 

 cases. A diagram, in which the logarithm of the concentration 

 is taken as the abscissa and the relative viscosity as the or- 

 dinate, brings these facts most clearly into view. Ammonium 



