96 



current aud to the uiovemeiit of ions by diftusion due to osmotic pressure 

 has been found to I)e approximately proportional to the increase in in- 

 ternal friction measured by the rate of flow through a capillary, indi- 

 cating friction as the immediate cause. 



The purpose of the investigation here reported was to attack the 

 problem by a method not hitherto used ai)parently in this connection. 

 The freezing point method was employed, and the solutions examined 

 were those of hydrochloric acid and sucrose. The freezing points detex-- 

 mined Avere those of water, of twice-normal ami twentieth-normal water 

 solutions of hydrochloric acid, of water solutions of sucrose containing 1, 

 5, 10, 25 aud 35 grams in 100 cubic centimeters, and of water solutions 

 of hydrochloric acid and sucrose of corresponding concentrations. The 

 ordinary Beckmauu apparatus was used. 



It was foimd that the loweriugs of the freezing point produced by 

 known weights of acid aud sugar mixed in a given quantity of water 

 was equal to the sum of tlie loweriugs produced by the same weights 

 of acid and sugar each dissolved separately in the same quantity of 

 water. This result harmonizes with those found by the other methods 

 mentioned above in showing no effect of the sugar on the degree of 

 ionization of the acid, and leading to the conclusion that the increase 

 in resistance to the current observed in corresponding solutions of hydro- 

 chloric acid on addition of siigav. was due wholly to an inci'oase in the 

 friction between the ions and the solutions. 



The author desires to express his appreciation of the expi'iinicntal 

 work done by Mr. H. E. Bachtenkiiclier. r..S.. at that time a stialeiit 

 in Piu'due Univeisity. 



Lafavptte. Indiana. December. l!Mi:]. 



